Sunday, June 29, 2014

Buffalo Crossing the Upper Missouri

Buffalo Crossing the Upper Missouri, George Catlin, 1832
 
Smithsonian American Art Museum
(Link)

“Near the mouth of White River, we met the most immense herd crossing the Missouri River---and from an imprudence got our boat into imminent danger amongst them, from which we were highly delighted to make our escape. It was in the midst of the ‘running season,’ and we had heard the ‘roaring’ (as it is called) of the herd, when we were several miles from them. When we came in sight, we were actually terrified at the immense numbers that were streaming down the green hills on one side of the river, and galloping up and over the bluffs on the other. The river was filled, and in parts blackened, with their heads and horns, as they were swimming about . . . furiously hooking and climbing on to each other. I rose in my canoe, and by my gestures and hallooing, kept them from coming in contact with us, until we were out of their reach.” (Catlin, Letters and Notes, vol. 2, no. 32, 1841; reprint 1973)

Saturday, June 28, 2014

Comanche Chasing Buffalo


  
Comanche Chasing Buffalo, George Catlin, 1846-1848

Smithsonian American Art Museum
(Link)

“There are, by a fair calculation, more than 300,000 Indians, who are now subsisted on the flesh of the buffaloes, and by those animals supplied with all the luxuries of life which they desire, as they know of none others. The great variety of uses to which they convert the body and other parts of that animal, are almost incredible to the person who has not actually dwelt amongst these people, and closely studied their modes and customs. Every part of their flesh is converted into food, in one shape or another, and on it they entirely subsist. The robes of the animals are worn by the Indians instead of blankets---their skins when tanned, are used as coverings for their lodges, and for their beds; undressed, they are used for constructing canoes---for saddles, for bridles---l'arrêts, lasos, and thongs. The horns are shaped into ladles and spoons---the brains are used for dressing the skins---their bones are used for saddle trees---for war clubs, and scrapers for graining the robes---and others are broken up for the marrow-fat which is contained in them. Their sinews are used for strings and backs to their bows---for thread to string their beads and sew their dresses. The feet of the animals are boiled, with their hoofs, for the glue they contain, for fastening their arrow points, and many other uses. The hair from the head and shoulders, which is long, is twisted and braided into halters, and the tail is used for a fly brush.” George Catlin completed this work in Paris between 1846 and 1848. (Catlin, Letters and Notes, vol. 1, no. 31, 1841; reprint 1973)

Supreme Court B.C. land-claim ruling has staggering implications for Canadian resource projects

Brian Hutchinson
National Post
June 26th, 2014
(Link)

"Thursday’s decision establishes conditions aboriginal groups must meet to press collective rights on territories outside their settlements or formal treaty boundaries.

"Written by Chief Justice Beverley McLachlin, the unanimous ruling says that aboriginal title “flows from occupation in the sense of regular and exclusive use of land … Occupation sufficient to ground aboriginal title is not confined to specific sites of settlement, but extends to tracts of land that were regularly used for hunting, fishing or otherwise exploiting resources and over which the group exercised effective control at the time of assertion of European sovereignty.”

"It means that economic development proposed by non-aboriginals — such as resource extraction and pipeline activity — requires explicit consent from host First Nations on land where the Supreme Court’s expanded concept of land title is established."


  Nemaiah Lake, in the claim area

Friday, June 27, 2014

Crow Lodge of Twenty-five Buffalo Skins

Crow Lodge of Twenty-five Buffalo Skins, George Catlin, 1832-1833

Smithsonian American Art Museum
(Link)

“The Crows, of all the tribes in this region . . . make the most beautiful lodge . . . they oftentimes dress the skins of which they are composed almost as white as linen, and beautifully garnish them with porcupine quills, and paint and ornament them in such a variety of ways, as renders them exceedingly picturesque and agreeable to the eye. I have procured a very beautiful one of this description, highly-ornamented, and fringed with scalp-locks, and sufficiently large for forty men to dine under. The poles which support it are about thirty in number, of pine, and all cut in the Rocky Mountains, having been some hundred years, perhaps, in use. This tent, when erected, is about twenty-five feet high, and has a very pleasing effect.” (Catlin, Letters and Notes, vol. 1, no. 7, 1841; reprint 1973)

Imagining Head-Smashed-In:  Aboriginal Buffalo Hunting on the Northern Plains
Jack W. Brink

Athabasca University Press
2008
p. 228
"Hides were critical to their survival.  Eventually, over many days, the hides from the slaughtered animals made their way from the kill site to the winter camp.  Here, people (mostly women, we believe) labored over them for days on end, converting them to winter footwear, bedding to sleep on and blankets to pull over you, cape-like robes to drape over your shoulders, some heavy clothing, and a wide variety of containers like bags, satchels, shields, and drums.  The amazing hide of bison had served the animal well in its lifetime, and so too it served the people who took it."

Thursday, June 26, 2014

"Sha-kó-ka, Mint, a Pretty Girl" wears a brain tanned dress

Sha-kó-ka as painted by George Catlin 1832

Smithsonian American Art Museum
(Link)

“A very pretty and modest girl,” George Catlin wrote, “twelve years of age, with grey hair! peculiar to the Mandans . . . There are very many, of both sexes, and of every age, from infancy to manhood and old age, with hair of a bright silvery grey; and in some instances almost perfectly white. This singular and eccentric appearance is much oftener seen among the women than it is with the men; for many of the latter who have it, seem ashamed of it, and artfully conceal it, by filling their hair with glue and black and red earth. The women, on the other hand, seem proud of it, and display it often in an almost incredible profusion, which spreads over their shoulders and falls as low as the knee. I have ascertained, on a careful enquiry, that about one in ten or twelve of the whole tribe are what the French call ‘cheveux gris,’ or greyhairs; and that this strange and unaccountable phenomenon is not the result of disease or habit; but that it is unquestionably a hereditary character which runs in families, and indicates no inequality in disposition or intellect. And by passing this hair through my hands, as I often have, I have found it uniformly to be as coarse and harsh as a horse’s mane; differing materially from the hair of other colours, which amongst the Mandans, is generally as fine and as soft as silk.” Catlin painted Sha-kó-ka at a Mandan village in 1832. (Catlin, Letters and Notes, vol. 1, no. 13, 1841, reprint 1973, and 1848 Catalogue, Catlin’s Indian Gallery, SAAM online exhibition)

The Two Hide Dress of the Upper Missouri
(Link)

The Ancient Process of Brain Tanning Hides
from An Ojibwe Elder's Art and Stories
(Link)

Imagining Head-Smashed-In:  Aboriginal Buffalo Hunting on the Northern Plains
Jack W. Brink
Athabasca University Press
2008

"Animals too wounded to stand posed little danger and were likely dispatched with heavy stone clubs, made with grooved mauls tied on to long wooden handles.  These were swung hard against the front of the skull, smashing in the bones and exposing the brain cavity - not only to kill the wounded beasts, but also to allow access to the brain, an organ much desired for the subsequent chore of tanning the hides.  Skulls are poorly preserved at Head-Smashed-In and are also conspicuously rare, but other buffalo jumps on the northern Plains clearly show this pattern of smashing the skulls." (page 163)

"Exploring the central Plains in the early eighteen hundreds, Edwin James recorded the general method of tanning bison hide:
The hide is extended upon the ground; and with an instrument resembling an adze, used in the manner of our carpenters, the adherent portions of the dried flesh are removed, and the skin rendered much thinner and lighter than before.  The surface is then plastered over with the brains or liver of the animal, which have been carefully retained for the purpose, and the warm broth of meat is also poured over it.  The whole is then dried, after which it is again subjected to the action of the brains and broth, then stretched in a frame, and while still wet, scraped with pumice-stone, sharp stones, or hoes, until perfectly dry.  Should it not yet be sufficiently soft, it is subjected to friction, by pulling it backwards and forwards over a twisted sinew.  This generally terminates the operation." (page 226)

Wednesday, June 25, 2014

Los cráneos de la Sima de los Huesos de Atapuerca


Juan Luis Arsuaga
Museo de la Evolucion Humana
June 23, 2014

Add it up: the genetic basis of ecological adaptation

Limnetic male stickleback (top), benthic female (bottom).
 
Katie Peichel
Add it up:  the genetic basis of ecological adaptation [in sticklebacks]
(Link)

Quantifying the Extent of Geographic Signature in the Human Genome

Lior Pachter
(Link) Youtube

Conference on Computation-Intensive Probabilistic and Statistical Methods for Large-Scale Population Genomics
(Simon's Institute for the Theory of Computing, Berkeley)
Feb. 18Feb. 21, 2014
(Link)

Tuesday, June 24, 2014

A post-glacial sea level hinge on the central Pacific coast of Canada

Hakai Protected Area (photo courtesy of Alder Creek)
 
 
Duncan McLaren, Daryl Fedje, Murray B. Hay, Quentin Mackie, Ian J Walker, Dan H. Shugar, Jordan B. R. Eamer, Olav B. Lian, Christina Neudorf
Available online 20 June 2014
DOI: 10.1016/j.quascirev.2014.05.023
(Link) open access
 
[Blog note:  As I've long been curious about the potential of British Columbia's coast as an early route into the Americas, it's wonderful to see this paper. I grew up in Vancouver and have both hiked and kayaked on the Central Coast. A friend of mine, John Clarke, was a renowned mountaineer with many first ascents of mountains in this area.  He was also a historian, public advocate for conservation of the British Columbia Coast Ranges and an advocate for First Nations people.  The Central Coast is one of extraordinary beauty and biodiversity (see for example on this blog Last Wild Wolves of British Columbia's North Coast).  For those who are interested in wilderness conservation, on the bottom of the right margin, I have a number of Twitter links put up by conservation groups.  Relevant to the Central Coast of British Columbia are Save the Great Bear and Haida Gwaii Communities Against Supertankers. I would also mention that Quentin Mackie, an author on the paper, frequently touches on conservation issues and discusses First Nations people and current events on his blog Northwest Coast Archaeology. The Koeye River, recently discussed on his blog, is an area researched in the paper. I'm waiting with expectation as the broader picture of this coastal migration route is reconstructed by these researchers!]
 
Abstract
 
Post-glacial sea level dynamics during the last 15,000 calendar years are highly variable along the Pacific coast of Canada. During the Last Glacial Maximum, the Earth's crust was depressed by ice loading along the mainland inner coast and relative sea levels were as much as 200 m higher than today. In contrast, some outer coastal areas experienced a glacial forebulge (uplift) effect that caused relative sea levels to drop to as much as 150 m below present levels. Between these inner and outer coasts, we hypothesize that there would have been an area where sea level remained relatively stable, despite regional and global trends in sea level change. To address this hypothesis, we use pond basin coring, diatom analysis, archaeological site testing, sedimentary exposure sampling, and radiocarbon dating to construct sea level histories for the Hakai Passage region. Our data include 106 newly reported radiocarbon ages from key coastal sites that together support the thesis that this area has experienced a relatively stable sea level over the last 15,000 calendar years. These findings are significant in that they indicate a relatively stable coastal environment amenable to long-term human occupation and settlement of the area. Our results will help inform future archaeological investigations in the region.
 
Figure 2.  Location of the study area on the Northwest Coast of North America.
 

Central Coast of British Columbia, showing the Hakai Protected Area and adjacent areas (map courtesy of Google Maps).


Figure 13.  Stylized cross-section of study area showing the effects of isostatic and eustatic adjustments and the presence of a forebulge on relative sea level through time.


Discussion
 
The Hakai West sea level curve (Fig. 12) reveals that relative sea level in the area has been within 10 m of present over the last 15,000 years. The Hakai East sea level curve shows more variation with sea level dropping 15.5 m over the same period. The data presented here demonstrate that a sea level ‘hinge’ existed between regions with higher and lower (than today) relative sea levels on the central Pacific coast of Canada (Fig. 13). The sea level hinge was found to be most stable in the Hakai West region. However, moraines and other glacial features on the landscape reveal that it is likely that much of the Hakai West region was under ice some time before 15,000 BP. During this time, with the increased volume of ice on land it is possible that the sea level hinge was located further offshore.

The Hakai area is a part of a larger region that extends southeast to northwest along the eastern shores of Queen Charlotte Sound, Hecate Strait, Dixon Entrance, and Clarence Channel along which we argue that a similar hinge-like area may be located (Fedje et al., 2004, McLaren, 2008 and McLaren et al., 2011; Shugar et al., in press, this volume). Migration of this hinge through time was dependent on local isostatic and global eustatic factors. The stability of any particular area within this region was dependent on localized factors pertaining to the amount of ice and tectonic activity. It is uncertain whether hinge areas as stable as Hakai West occur elsewhere along the coast.

The degree of stability of the shoreline in the Hakai region, and in the Hakai West area in particular, is remarkable. Elsewhere, the interplay between eustatic, isostatic, and tectonic factors tend to result in substantial changes to shoreline elevation through time. This stability means that, in the Hakai region, isostatic rebound was occurring at equal pace with global eustatic sea level rise at the end of the last glaciation. Between 14,000 and 10,000 Cal BP eustatic sea level rise was approximately 1.2 cm per year (Fairbanks, 1989). As relative sea level remained essentially constant, isostatic rebound rates for the Hakai West region must have been comparable. This pattern also suggests that the area has remained relatively tectonically stable over the Holocene accounting for very little change in relative sea level (see Shugar et al., in press, this volume for a discussion of tectonics and sea level change).

Places with stable shorelines allow relatively uninterrupted accumulation of archaeological deposits over long periods of time. In theory, these larger accumulations should be easier to find and they would be expected to retain long records of cultural and ecological information. Places where early archaeological deposits occur may be similar to places that are suitable for coastal habitation today, such as pocket beaches, harbours, and tombolos. This can be contrasted with areas such as Goose Bank, Haida Gwaii, and non-glaciated regions around the globe where late-Pleistocene shorelines are drowned by up to 150 m rendering them very difficult to access, or inland areas such as Kitimat or the Fraser Valley where relative sea level was 200 m higher than today and where significant glaciations occurred up until the end of the Pleistocene.

Relative stability in sea level allows for the establishment of persistent places across the landscape. Of the archaeological sites tested, four show persistent occupation for 10,000 or more years: Namu (ElSx1), Kildidt Narrows (ElTa18), Triquet Island (EkTb9), and Pruth Bay (EjTa15). It is highly likely that there are several other sites in the area with equally long records. This pattern of site re-use and persistence differs from settlement patterns on Haida Gwaii (200 km west of the study area) where early and late period sites tend not to co-occur (Mackie and Sumpter, 2005) and where Holocene sea level rose to 15 m ahht and then fell back to modern levels.

The identification of a sea level hinge is of particular interest for investigations into early period archaeology of the Northwest Coast and the peopling of the Americas (Fedje et al., 2004 and Mackie et al., 2013). Fladmark (1979) presented a compelling argument in which the Northwest Coast is depicted as the most likely route by which early human inhabitants of the Americas circumnavigated the continental ice sheets that covered much of Canada during the Last Glacial Maximum. In their comprehensive review of the timing of the Last Glacial Maximum, Clague et al. (2004) argue that post glacial human occupation of outer coastal areas of Southeast Alaska and British Columbia could have occurred as early as 16,000 Cal BP. Early archaeological sites to the south of the ice sheets including Paisley Caves (Gilbert et al., 2008 and Jenkins et al., 2012) in Oregon, and Manis Mastodon (Gustafson et al., 1979 and Waters et al., 2011) in Washington State, reveal that the western margins of North America was occupied by at least 13,800 Cal BP. The research presented here has revealed potential shoreline targets for archaeological prospection up to 15,000 years old, providing potential for future investigations into the early human occupation of the Americas.

Conclusions
 
This paper describes a relative sea level history spanning the past 15,000 years for the Hakai Passage region on the central Pacific coast of Canada. Data was gathered using geological and archaeological methods. Overall, the research presented here demonstrates that relative sea level remained remarkably constant through this 15,000 year period despite the large scale changes resulting from global eustatic and regional isostatic processes during the same time period. The evidence reveals that isostatic rebound kept pace with eustatic sea level change and uplift over this period. Part of the reason for this stability is that the study area is located on a sea level hinge between a region with higher relative sea level to the east and lower relative sea level to the west. The sea level history of the study area demonstrates that sea level change in ice-proximal regions can be highly variable and localized (see also Shugar et al. in press, this volume). Attempts to model sea level change in any region along the Pacific coast of Canada and southern Alaska need to take local, regional, and global influences into account. The sea level history presented here will enable research to more effectively target sites that have the potential to lengthen the record of human occupation in the region to early post-glacial times.


Mount Saugstad, east of Calvert Island and the Hakai wilderness (from Coastmountains blog)

Monday, June 23, 2014

Inferring human population size and separation history from multipule genome sequences

Stephen Schiffels, Richard Durbin

Nature Genetics
Accepted 30 May 2014; published 22 June 2014;
doi:10.1038/ng.3015
Nature (Link)
Open Access prepint on BioRXiv (Link)
Author comments on the paper (Link)
 
[Blog note:  The African populations examined in this paper are: Yoruban (YRI), Maasai (MKK), and Luhya (LWK)(Kenya).  CEU is a population commonly used to represent Europeans.]
 
Abstract

The availability of complete human genome sequences from populations across the world has given rise to new population genetic inference methods that explicitly model ancestral relationships under recombination and mutation. So far, application of these methods to evolutionary history more recent than 20,000–30,000 years ago and to population separations has been limited. Here we present a new method that overcomes these shortcomings. The multiple sequentially Markovian coalescent (MSMC) analyzes the observed pattern of mutations in multiple individuals, focusing on the first coalescence between any two individuals. Results from applying MSMC to genome sequences from nine populations across the world suggest that the genetic separation of non-African ancestors from African Yoruban ancestors started long before 50,000 years ago and give information about human population history as recent as 2,000 years ago, including the bottleneck in the peopling of the Americas and separations within Africa, East Asia and Europe.

Divergence from and Within African Populations
 
MSMC lets us explicitly study the genetic separation between two populations as a function of time by modeling the relationship of multiple haplotypes, half of which are from one population and half of which are from the other. From analyzing four haplotypes for each pair of populations, we found that all relative cross coalescence rates between any non-African population and the Yoruba were very similar and exhibited a slow, gradual divergence beginning earlier than 200,000 years ago and lasting until about 40,000 years ago (Fig. 4a). This similarity in rates gives additional information beyond estimates of population size and is consistent with all non-African populations diverging as a single population from the Yoruban ancestors.

To understand whether the gradual divergence in relative cross coalescence rate between the YRI and non-African ancestors was due to the inability of MSMC to detect rapid changes (Fig. 2b) or due to true ongoing genetic exchange, we compared its results with simulated clean split scenarios at three different time points in the past (Fig. 4c). This comparison showed that no clean split could explain the inferred progressive divergence in relative cross coalescence rate. In particular, the early beginning of the divergence would be consistent with an initial formation of distinct populations before 150,000 years ago, whereas the late end of the decline would be consistent with a final split around 50,000 years ago. This comparison suggests a long period of partial divergence with ongoing genetic exchange between the Yoruban and non-African ancestors that began beyond 150,000 years ago, with population structure within Africa, and lasted for over 100,000 years. The median point of this divergence was around 60,000–80,000 years ago, at which time there was still substantial genetic exchange, with half the coalescences between populations and half within. We also observed that the rate of genetic divergence was not uniform but could be roughly divided into two phases. First, up until about 100,000 years ago, the two populations separated more slowly, whereas after 100,000 years ago, the rate of genetic exchange decreased faster. We note that the fact that the relative cross coalescence rate did not reach 1, even around 200,000 years ago (Fig. 4c), might be owing to later admixture of archaic populations such as the Neanderthals into the CEU population after its split from the YRI ancestral population [29].

We also saw extended divergence patterns in eight-haplotype analysis between the ancestors of the three African populations (Fig. 4a), with the LWK and YRI ancestral populations being closest and the MKK ancestral population showing a very slow increase in relative cross coalescence rate going back in time with the YRI and LWK ancestral populations. These declines in rate were all more gradual than those shown in Figure 4b between out-of-Africa populations, suggesting that the separations of African populations were also not clean splits but gradual separations, perhaps reflecting complex ancestral structure with admixture. In addition, we saw a different separation history between CEU and MKK ancestral populations compared to the LWK and CEU ancestral populations, which in turn was very similar to our estimates of the YRI-CEU separation. Our results suggest that the Maasai ancestors were mixing extensively with non-African ancestors until about 80,000 years ago, much later than the separation of the YRI and non-African populations. This observation is consistent with a model in which the Maasai ancestors and non-African ancestors formed sister groups, which together separated from West African ancestors and continued to extensively mix until much closer to the time of the actual out-of-Africa migration. Nonzero estimates of relative cross coalescence rate between the MKK and CEU ancestors after 50,000 years ago are probably confounded by more recent admixture from non-African populations back into East African populations, including the Maasai [30, 31].

Sunday, June 22, 2014

Neandertal roots: Cranial and chronological evidence from Sima de los Huesos


Science
Vol. 344 no. 6190 pp. 1358-1363
DOI: 10.1126/science.1253958

(Link)

[Blog note:  This paper, elucidating the anatomical features of the Sima de los Huesos skulls, has been widely covered in the press in the last few days.  For instance, in the GuardianNeanderthal faces emerge from the gloom of a Spanish cave.  Rather than commenting, I thought I would make it easier for the general public to access essential sections of the paper. (I have not included the intermediate sections on dating of SH (Sima de los Huesos), cranial capacities and encephalization quotient, cranial vault comparisons, facial skeleton, basicranium, or mandibles and dentition.)  For interested readers who are non expert in the area of cranial morphology, supplementary section S2 provides descriptive statistics on the parameters discussed.  Additionally, several youtube videos are helpful: cranial anatomy and cranial landmark definitions.  Some of the skull features discussed are ones that most people are aware of on their own head:  the occipital structure on the back of the head, the bumps on the side of the head above the ear, and various structures on the front of the face such as the brow and jaw.  The intermediate sections of the paper discuss how these vary in the SH specimens and other hominins and for this reason, a careful reading of the full paper is instructive toward understanding the points made in the discussion section.]

Abstract

Seventeen Middle Pleistocene crania from the Sima de los Huesos site (Atapuerca, Spain) are analyzed, including seven new specimens. This sample makes it possible to thoroughly characterize a Middle Pleistocene hominin paleodeme and to address hypotheses about the origin and evolution of the Neandertals. Using a variety of techniques, the hominin-bearing layer could be reassigned to a period around 430,000 years ago. The sample shows a consistent morphological pattern with derived Neandertal features present in the face and anterior vault, many of which are related to the masticatory apparatus. This suggests that facial modification was the first step in the evolution of the Neandertal lineage, pointing to a mosaic pattern of evolution, with different anatomical and functional modules evolving at different rates.

Introduction

The course of human evolution in the Middle Pleistocene is controversial (1, 2, 3, 4). Most of the debate has focused on taxonomic and phylogenetic questions, particularly surrounding the origin of Neandertals and modern humans (5, 6, 7, 8, 9). The European Middle Pleistocene fossil record is important for the timing and pattern of emergence of the Neandertals, but it is composed mainly of isolated and geographically dispersed remains of diverse chronologies. This complicates the evaluation of competing evolutionary scenarios. One of these scenarios, known as the “accretion model,” rests on two hypotheses: one regarding the timing of the origin of the Neandertal lineage and the other regarding the pattern of morphological change (1, 5, 10). Under this model, the Neandertals would have deep roots in the Middle Pleistocene, branching off as early as Marine Isotope Stage 11 [around 400,000 years ago (400 ka)] (5, 11), or even earlier. In addition, the model suggests that the full suite of derived Neandertal features (anatomical and functional modules) did not emerge as a single package, but that different features appeared separately and at different times. In particular, Neandertal facial morphology evolved first, followed by changes in the neurocranium.
                 
Here we analyze a collection of 17 well-dated skulls, including several previously unpublished specimens [Fig. 1, supplementary text S1 (12), and table S1], that can be used to test the two pillars of the accretion model. This sample comes from the Sima de los Huesos (SH) Middle Pleistocene site in the Sierra de Atapuerca (Spain) and derives from a single paleo-deme (p-deme). Because the accretion model is based mainly on nonmetric traits (5), our analysis emphasizes the pattern of expression of morphological features in the SH hominins, although the descriptive statistics for the principal craniometrical variables in the SH sample are also provided (table S2).

    Fig. 1    Cranium 9 (top left), Cranium 15 (top right), and
    Cranium 17 (bottom) from SH.  (Scale bar: 3 cm.)
 
 
Discussion

The chronology established for LU-6 and LU-7, on the basis of several independent techniques with reproducible results, provides a minimum age of ~430 ka for the SH human fossils, which is some 100 ka younger than previously reported (37). With this new age, the SH hominins are now the oldest reliably dated hominins to show clear Neandertal apomorphies. Notably, the improved chronology for the SH assemblage is compatible with the latest dental and genetic evidence for Middle Pleistocene evolutionary divergences (38, 39) and enables us to state with certainty that the modern human/Neandertal most recent common ancestor dates to sometime before ~430 ka (pre–MIS 11).                   

The considerably enlarged SH cranial sample is morphologically quite homogeneous. In addition to some plesiomorphic traits in the cranial vault (such as the low position of the maximum cranial breadth), derived Neandertal traits are present in the midfacial projection, morphology of the supraorbital torus, and the glenoid cavity. Although the occipital morphology is not Neandertal-like, there is a flat supratoral surface that may be derived in the direction of the Neandertals. Finally, the SH mandibles and the dentition also show a derived Neandertal pattern, together with some distinctive dental features. In sum, the SH sample shows a constellation of derived Neandertal facial, dental, mandibular, and glenoid features that appears to represent a single functional masticatory complex. At the same time, the cranial vault lacks Neandertal specializations. This mosaic pattern fits the prediction of the accretion model for the first stage of Neandertal evolution.

Concerning the taxonomy of the SH fossils, we have long maintained that the SH hominins are members of the Neandertal lineage (16, 40). Based on the cranial evidence, we have proposed that the SH fossils, as well as the rest of the European early and middle Middle Pleistocene specimens, should be assigned to the species Homo heidelbergensis defined in a broad sense to include fossils with a generally more primitive morphology than the late Middle Pleistocene and Late Pleistocene Neandertals, even if they exhibit some derived Neandertal traits (19). However, the difficulty with identifying derived Neandertal features in the Mauer mandible, the type specimen of H. heidelbergensis, contrasts strongly with the presence of numerous Neandertal apomorphies in the SH mandibles (41). On this basis, we suggest that the SH sample be removed from the H. heidelbergensis hypodigm. An alternative view of H. heidelbergensis is as a Middle Pleistocene taxon that includes only fossils that lack any Neandertal apomorphies, and, in this restricted sense, the species is seen as the stem group for Neandertals and modern humans (7).

In addition, the new evidence presented here based on cranial morphology confirms that the SH population differs from some other European MPHs, such as Ceprano and Arago, that do not exhibit the suite of derived Neandertal features seen in SH. Thus, more than one evolutionary lineage appears to have coexisted during the European Middle Pleistocene (42), with that represented by the SH sample being phylogenetically closer (i.e., a sister group) to the Neandertals.

Some authors have, indeed, recommended that the SH fossils be included in H. neanderthalensis (5, 7) as early members of this evolutionary lineage. However, although we agree that the SH hominins are members of the Neandertal clade, the present analysis has shown that they differ from Neandertals in several cranial regions that are considered taxonomically diagnostic of H. neanderthalensis. We argue that the SH p-deme is sufficiently different from that of H. neanderthalensis so as to be considered a separate taxon. Whether this difference should be recognized on the specific or subspecific level is currently an open question.

Related to this, a nearly complete mitochondrial genome recently sequenced from a SH femur (43) groups with two Denisovan individuals rather than with Neandertals. This surprising result might seem to contradict our morphological interpretation of the SH population belonging to the Neandertal clade. However, based on analysis of their nuclear genome, the Denisovans are considered a sister group to Neandertals (44). It is possible that two deeply divergent mitochondrial DNA (mtDNA) lineages coexisted in the SH population, one that later characterizes the Denisovans and another (as yet undocumented) mtDNA lineage that became fixed in Neandertals. Alternatively, it is possible that gene flow from another hominin population (not belonging to the Neandertal clade) brought the Denisova-like mtDNA into the SH population or its ancestors. The latter scenario would imply that two different hominin clades (the Neandertal clade and another more primitive clade) coexisted in Europe for some time, an interpretation that is not contradicted by the fossil evidence. Retrieving additional mitochondrial or nuclear DNA sequences from the SH sample may help clarify our understanding.

It is important to underline that the morphology of the SH crania, mandibles, and teeth is very constant for those features that have been considered taxonomically relevant, without polymorphisms or different trait combinations. This finding was not a foregone conclusion, because the SH variation could have encompassed the range of variation found among different European fossils that are broadly contemporaneous. However, it is clear that there is more variation between demes in the European mid Middle Pleistocene than there is within the SH deme. The morphological variability among a single p-deme can be used to distinguish between anagenetic (linear) or cladogenetic (branching) patterns of evolution. The former implies that the population as a whole (of which any particular p-deme is but one component) evolves in a similar direction throughout its geographic range, and that the individual p-demes show a large degree of intrademe morphological variation. In contrast, the latter is more consistent with the cladogenetic model and implies that evolutionary change occurs via sorting between p-demes, which individually show little intrademe variation.

Although the accretion model is potentially consistent with either an anagenetic or cladogenetic mode of evolution, our morphological analysis of the SH sample fits the latter more closely. Moreover, the scenario of several demographic crashes influenced by climatic crisis throughout the European Middle Pleistocene would produce p-deme sorting, with extinction of some populations and replacement by others (5). The presence in the SH skulls of Neandertal-derived regions that can be functionally related in modules, together with others that remain primitive, combined with the pre-MIS 11 age of the sample, confirms the accretion model of Neandertal origins. Finally, the finding that these derived Neandertal features are functionally related with the masticatory complex suggests that the origin of the Neandertal clade coincides with a masticatory specialization.

Wednesday, June 18, 2014

Vocal tract length and formant frequency dispersion correlate with body size in rhesus macaques

W. Tecumseh Fitch
J. Acoust. Soc. Am. 102, 1213 (1997)
http://dx.doi.org/10.1121/1.421048

Abstract

Body weight, length, and vocal tract length were measured for 23 rhesus macaques (Macaca mulatta) of various sizes using radiographs and computer graphic techniques. Linear predictive coding analysis of tape-recorded threat vocalizations was used to determine vocal tractresonance frequencies (“formants”) for the same animals. A new acoustic variable is proposed, “formant dispersion,” which should theoretically depend upon vocal tract length. Formant dispersion is the averaged difference between successive formant frequencies, and was found to be closely tied to both vocal tract length and body size. Despite the common claim that voice fundamental frequency F0 provides an acoustic indication of body size, repeated investigations have failed to support such a relationship in many vertebrate species including humans. Formant dispersion, unlike voice pitch, is proposed to be a reliable predictor of body size in macaques, and probably many other species.

Cochlear Labyrinth Volume and Hearing Abilities in Primates

E. Christopher Kirk and Ashley D. Gosselin-Ildari
The Anatomical Record
Volume 292, Issue 6, pages 765–776, June 2009
DOI: 10.1002/ar.20907
(Link)

Abstract

The primate cochlea is a membranous, fluid-filled receptor organ that is specialized for sound detection. Like other parts of the inner ear, the cochlea is contained within the bony labyrinth of the petrous temporal bone. The close anatomical relationship between the bony cochlear labyrinth and the membranous cochlea provides an opportunity to quantify cochlear size using osteological specimens. Although mechanisms of cochlear frequency analysis are well studied, relatively little is known about the functional consequences of interspecific variation in cochlear size. Previous comparative analyses have linked increases in basilar membrane length to decreases in both the high and low frequency limits of hearing in mammals. However, these analyses did not consider the potentially confounding effects of body mass or phylogeny. Here, we present measurements of cochlear labyrinth volume in 33 primate species based on high-resolution computed tomography. These data demonstrate that cochlear labyrinth volume is strongly negatively allometric with respect to body mass. Scaling of cochlear volume in primates is very similar to scaling of basilar membrane length among mammals generally. Furthermore, an analysis of 10 primate taxa with published audiograms reveals that cochlear labyrinth volume is significantly negatively correlated with the high frequency limit of hearing. This result is independent of body mass and phylogeny, suggesting that cochlear size is functionally related to the range of audible frequencies in primates. Although the nature of this functional relationship remains speculative, our findings suggest that some hearing parameters of extinct taxa may be estimated using fossil petrosals.

From the body of the paper:

Use of the cochlear labyrinth to make inferences about mammalian hearing abilities is based on the observation that the gross dimensions of the cochlea and its constituent tissues are correlated with the range of frequencies that can be detected by a species (West, 1985; Echteler et al., 1994). West (1985) demonstrated that the length of the basilar membrane is significantly negatively correlated with both the high and low frequency limits of hearing. In other words, as basilar membrane length increases in mammals, the range of audible frequencies shifts downward into relatively lower frequencies. As a result, mammals with absolutely long basilar membranes tend to have comparatively good low-frequency hearing, while mammals with absolutely short basilar membranes have comparatively good high-frequency hearing. Elephants, for example, have a basilar membrane length of about 60 mm and a range of audible frequencies between 0.18 and 10.5 kHz (West, 1985). By contrast, the house mouse has a basilar membrane length of only 7 mm, and a range of audible frequencies between 2.7 and 79 kHz (West, 1985).

Similar correlations between basilar membrane length and hearing thresholds were reported by Echteler et al. (1994) for mammals with “unspecialized” cochleas. However, these authors also demonstrated that species with substantially nonlinear cochlear frequency-place maps (“hearing specialists”) do not conform to this general mammalian trend (Echteler et al., 1994). From a practical standpoint, these results suggest that the dimensions of the cochlea may be used to estimate the high and low frequency limits of hearing for most mammals (West, 1985; Echteler et al., 1994). By contrast, the hearing abilities of taxa with acoustic foveae (e.g., dolphins and horseshoe bats) and/or substantial discontinuities in basilar membrane dimensions (e.g., mole rats) are more difficult to predict (Echteler et al., 1994). According to the criteria of Echteler et al. (1994), primates may be considered “hearing generalists”. None are known to possess acoustic foveae, none are specialized for echolocation or seismic hearing, and all species that have been studied exhibit typical cochlear frequency-place maps that lack plateaus or discontinuities (Greenwood, 1990). As a result, it is theoretically possible to derive predictions about the hearing abilities of primates based on the anatomy of the cochlea and cochlear labyrinth. Specifically, the findings of West (1985) and Echteler et al. (1994) suggest that increases in the length of the basilar membrane and resulting increases in the size of the cochlea should be correlated with a downward shift in the range of audible frequencies.

Table 1:  Cochlear labyrinth volumes in primates

 

Discussion

The results of this analysis provide further support for the conclusion that the dimensions of the cochlea influence hearing abilities in mammals. Previous research has shown that basilar membrane length is correlated with both the high and low frequency limits of hearing in mammals with unspecialized cochleas (West, 1985; Echteler et al., 1994). The present analysis demonstrates that cochlear size in primates (as estimated by the volume of the cochlear labyrinth) scales with body mass in a manner very similar to the scaling of basilar membrane length among mammals generally. In the comparative samples used here (Tables 1 and 2), cochlear labyrinth volume and basilar membrane length are each positively correlated with body mass (r = 0.894 and 0.939, respectively). Furthermore, both cochlear variables scale with strong negative allometry relative to body mass. Although cochlear labyrinth volume in primates demonstrates slightly greater negative allometry (RMA slope = 0.36) than basilar membrane length in mammals (RMA slope = 0.44) (Figs. 3 and 4), the RMA regression slope confidence intervals for both variables overlap. These similar scaling relationships support the expectation that cochlear size and basilar membrane length are closely linked. Indeed, it seems reasonable to expect that if selection acts to increase or decrease the length of the basilar membrane, then there should be correlated changes in cochlear volume. While caution in interpreting our data is warranted given the fact that the comparative samples for cochlear labyrinth volume (Table 1; primates) and basilar membrane length (Table 2; mammals generally) include different taxa, these results are consistent with the hypothesis that both cochlear variables should have a similar relationship with hearing abilities.

These expectations are largely borne out by our analysis of the relationship between cochlear labyrinth volume and hearing abilities in primate species with published audiograms (Heffner, 2004). Although cochlear labyrinth volume is not significantly correlated with either the best frequency of hearing (=frequency with lowest absolute detection threshold) or the total hearing range (= range of audible frequencies at 60 dB SPL), cochlear labyrinth volume is significantly negatively correlated with both the high and low frequency limits of hearing (Figs. 5a and 6a). In other words, as cochlear size increases, the range of audible frequencies shifts downward. These results are robust: even with the relatively small samples considered here, cochlear labyrinth volume alone can explain 61% of the variation in high frequency limit and 63% of the variation in low frequency limit. In this respect, our findings for cochlear size in primates closely match the results reported by West (1985) and Echteler et al. (1994) for basilar membrane length in a comparative sample of 9 mammalian species.

One potential criticism of the analyses presented by West (1985) and Echteler et al. (1994) is that both failed to address the influence of body mass and phylogeny. Indeed, it has been known for decades that high frequency limit is correlated with head and body size (Masterton et al., 1969; Heffner and Heffner, 1992, Heffner, 2004). This correlation has typically been explained as a result of selection for efficient sound localization at different head sizes. According to Heffner:

"Mammals with small heads (or, more precisely, short travel times for sound as it travels from one ear to the other) hear higher frequencies than mammals with large heads. The explanation for this relationship does not lie in the physical scaling of the auditory bulla and cochlea, with smaller middle and inner ears being associated with better high frequency hearing and larger ears being associated with better low-frequency hearing… In the case of high-frequency hearing, the explanation for the close correlation with head size… is that being able to detect high frequencies allows mammals to localize sound using pinna cues and spectral differences between the ears." (p. 1115; Heffner, 2004)

If this scenario is correct, then the size of the cochlea and length of the basilar membrane have no functional relationship with high frequency limit per se. In this case, the significant negative correlations between cochlear size variables (Table 1; West, 1985; Echteler et al., 1994) and high frequency limit would be the spurious byproduct of independent correlations between cochlear size, high frequency limit, and head/body size. The results of the present analysis, however, do not support this conclusion. While cochlear labyrinth volume and high frequency limit are both significantly correlated with body mass (Figs. 3 and 5b), the correlation between high frequency limit and cochlear volume (r = −0.78; P = 0.0074; Fig. 5a) is stronger than the correlation between high frequency limit and body mass (r = −0.68; P = 0.0321). Furthermore, the relationship between cochlear labyrinth volume and high frequency limit remains significant when independent contrasts are used to minimize the influence of phylogenetic effects. By comparison, independent contrasts of body mass and high frequency limit are not significantly correlated. More importantly, when a partial correlation analysis is used to hold the effects of body mass constant, cochlear labyrinth volume remains significantly correlated with high frequency limit (Fig. 7a). These results indicate not only that high frequency limit decreases with increasing absolute cochlear size, but that species with relatively large cochleas for their body size also have relatively low high frequency limits. In other words, at a given body size, species with smaller cochleas tend to have better high frequency hearing than species with larger cochleas.

The case for a functional relationship between cochlear size and low frequency limit is less convincing than that for high frequency limit. Although cochlear labyrinth volume is significantly negatively correlated with low frequency limit (r = −0.79; P = 0.0186), the correlation between body mass and low frequency limit is stronger (r = −0.84; P = 0.0089) (Fig. 6a,b). Furthermore, when a partial correlation analysis is used to hold body mass constant, cochlear labyrinth volume is no longer significantly correlated with low frequency limit (Fig. 7b).

These differences in the results for high frequency limit and low frequency limit beg the question of precisely how cochlear size might influence hearing abilities in mammals. Passive frequency analysis in the cochlea is generally attributed to the existence of a resonance gradient along the length of the basilar membrane, with the basal region of the basilar membrane having a higher resonant frequency than more apical regions (Echteler et al., 1994; Purves et al., 2008). This resonance gradient is thought to be largely dependent on variation in the mass and stiffness of the basilar membrane, leaving the mechanical significance of variation in basilar membrane length or the absolute size of the cochlea unclear. Although it is tempting to speculate that the mass of the cochlear fluids might also have a resonant effect on cochlear tuning, a great many factors influence cochlear mechanics (Dallos et al., 1996; Gummer, 2003) and a discussion of their potential relationship to cochlear size is well beyond the scope of the present analysis. Accordingly, while our data show a robust negative correlation between cochlear volume and high frequency limit in primates that is independent of body mass and phylogeny, the precise mechanism (or mechanisms) responsible for this relationship remains unknown.

It is also not immediately evident how interspecific variation in the high and low frequency limits of hearing influence primate ecology. Although the demands of sound localization are doubtless important (Masterton et al., 1969; Heffner and Heffner, 1992, Heffner, 2004), variation in habitat acoustics, diet, predation, and intraspecific communication may also exert a selective influence on hearing abilities (Morton, 1975; Waser and Brown, 1986; Zimmerman et al., 1995; de al Torre and Snowdon, 2002; Brumm and Slabbekoorn, 2005). Although these ecological relationships remain to be elucidated, the results of the present analysis suggest that the evolution of primate hearing abilities can be studied through an examination of the bony cochlear labyrinth. Cochlear labyrinth volume, in particular, can be used to estimate the high frequency limit of hearing. Similarly, Coleman and Boyer (2008) have recently reported that the length of the cochlea [3] can be used to estimate low frequency sensitivity in euarchontans. These analyses hold out the possibility that some parameters of the audiogram can be reconstructed for fossil species with suitably preserved bony labyrinths. Ultimately, such conclusions may be linked to differences in auditory ecology, as with divergent cochlear specializations for echolocation in odontocetes and low frequency communication in mysticetes (Fleischer, 1976; Ketten, 1992; Luo and Eastman, 1995; Geisler and Luo, 1996; Luo and Marsh, 1996).

Tuesday, June 10, 2014

The Case for Low Frequency Sound Production by Palaeolithic Hunters as an Aid to Mammoth Hunting

Marnie Dunsmore
marniedunsmore@earthlink.net
10 June 2014

African elephants produce low frequency rumbles for contact calling and bonding.  Interestingly, the contact calling rumbles are produced mostly below 200Hz.  It is postulated that elephants deliberately produce these ultra low frequency contact calls to increase the distance of their communication [1].

It should be noted that elephant calling rumbles, when observed with an acoustic spectrogram, appear to be not only low frequency, but also polyphonic [1].

Mammoths are closely related to African elephants and were approximately the same size with approximately the same trunk length [2].  Given the evolutionary advantage to being able to communicate over long distance, it is probable that mammoths retained contact calling along with elephants.  It is therefore likely that mammoths also produced low frequency calling rumbles somewhere in the range below 200Hz.

Recently, it has been proposed that the extinction of the mammoth was at least partly the result of human hunters [3], aided by their dogs or wolf-dogs [4].

Given evident aggressive hunting for megafauna by humans, and in particular, the hunting of mammoths to extinction [2], it is worthwhile to consider other technologies that humans might have used in the hunting of mammoths.  For instance, it has been noted that several instruments have a world wide distribution, including the bullroarer, the drum and many blown pipe instruments (flutes, pipes, didgeridoo, gaida) [5].  A small number of these musical instruments produce loud, low frequency sound below 200Hz, in the "rumble band" of elephants, including the bullroarer [6], the murgu or amyrga [7][8], and the gaida [9].  Certain large drums, including plank and log drums, also produce sound below 200Hz, but they are not easily transportable on the body of a person or are difficult to reassemble [5].

We cannot know if humans used portable, low frequency sound producers to confuse, terrify or mimic the mammoths.  However, there are many examples from very early times of humans mimicking birds for hunting purposes [5][6].  It would probably have been conceptually possible for early modern humans to transfer hunting concepts used for bird hunting to the more yield worthy task of mammoth hunting.

Ethnographic studies of musical instruments have noted the widespread use of the bullroarer by many hunter-gatherer societies including the Nenets in Siberia [5], Blackfoot and Sioux [10] and other groups in the Americas [11], and the Australian Aborigines [6].  In Europe, spectacularly, a bullroarer was excavated in 1930 at the Magdalenian site of La Roche de Birol, Lalinde, in the Dordogne [10].  A 5000-year-old slate bullroarer was found in northern Norway in 1991 [11].

Long flutes such as the Tuvan long amyrga also produce sound below 200Hz.  This instrument and shorter versions of it, were used in South Siberia to hunt Marals, a large deer [7].  The Tuva are also noted throat singers and often combine throat singing with musical instruments [8].  Some performances of their music retain the quality of mimicking animal sounds.  However, it should be noted that without the use of highly technical singing, the amyrga, like all simple flutes, cannot produce the polyphonic quality of an elephant rumble.  The sound power of flutes is also limited, especially at low frequency.

This is not the case with the multi-piped gaida/bagpipe, which produces a loud, low frequency drone below 200Hz on one pipe, while adding one or more additional playing pipes to allow the production of higher frequency variable tones above the drone [9].  It is a traditional instrument of Europe, Southwest Asia and North Africa.  The bag part of the gaida, traditionally made of animal hide, is perishable and would therefore not appear in archaeological sites.  It is possible that flutes now being found at Palaeolithic sites in Eurasia [10], especially if found in pairs or groups, and at mammoth sights, might have been used as gaidas in the aid of hunting.

In addition to being used for mammoth hunting, it is likely that the low frequency bullroarer, gaida and amyrga were used for long distance communication.  Elephants and large whales both take advantage of their ability to produce low frequency noise to communicate over long distances [1][14].  It is well documented that humans do this with drums [12] and it is highly probably that humans took advantage of these loud, low frequency instruments to communicate.  It is also probable that other megafauna, such as the bison and reindeer, were hunted using these instruments.  Given the ethnographic evidence, in addition to hunting and communication, these instruments became incorporated into sacred ceremonies and celebrations.  That being said, the retention of the bullroarer by many hunter-gatherer groups, especially in areas where the mammoth has gone extinct only in the last twelve thousand years [2][10][13], suggests that low frequency sound production was an important tool used by Palaeolithic hunters to terrify, confuse or control mammoths, and aid their demise.


References

[1Angela S. Stoeger, Gunner Heilmann, Matthias Zeppelzauer, André Ganswindt, Sean Hensman, and Benjamin D. Charlton, Visualizing Sound Emission of Elephat Vocalizations:  Evidence for Two Rumble Production Types.  PLOS One, November 14, 2012.  DOI: 10.1371/journal.pone.0048907

[2]  VI International Conference on Mammoths and Their Relatives, Grevena and Siatista, Western Macedonia, Greece, 5-12 May 2014.

[3] Christopher Sandom, Søren Faurby, Brody Sandel and Jens-Christian Svenning, Global late quaternary megafauna extinctions linked to humans, not climate change.  Proc. R. Soc. B 2014 281, 20133254, 4 Jun 2014.

[4]  Pat Shipman, How do you kill 86 mammoths? Taphonomic investigations of mammoth megasites.  Quaternary International, 19 May 2014.

[5]  Roger Blench, Using Ethnography to Reconstruct the Culture of Early Modern Humans.  December 2007.

[6]  Neville H. Fletcher, Australian Aboriginal Musical Instruments:  The Didjeridu, The Bullroarer and the Gumleaf.  Acoustics Australia, 2003

[7] Sevyan Vainshtein, Nomads of South Siberia, Cambridge University Press, 1980, pp. 172 and 173.

[8] Nachyn Choodu plays the amyrga, Millennium Stage, Kennedy Center, Washington, DC, 6 August 2009.

[9] Haris Sarris, Panagiotis Tzevelekos, "Singing like the gaida bagpipe": an ethnomusicological and acoustical approach.  In: K. Maimets-Volt, R. Parncutt, M. Marin & J. Ross (Eds.)  Proceedings of the third Conference on Interdisciplinary Musicology (CIM07), Tallinn, Estonia, 15-19 August 2007.

[10]  Anton Killin, Musicality in human evolution, archaeology and ethnography.  Biol Philos, 21 February 2014, DOI 10.1007/s10539-014-9438-y

[11] Wikipedia, Bullroarer page.

[12]  Marnie Dunsmore, Drums and Drumming Language Across West Africa, 25 June 2011.

[13]  Iain Morley, The prehistory of music: human evolution, archaeology, and the origins of musicality. Oxford University Press, 2013.

[14]  Secrets of Whales' Long Distance Songs are Being Unveiled, Science Daily, 2 March 2005.


Youtube and Other Video

Gaida (Bulgarian)
Bullroarer
Amyrga
The Elephant Documentary

"Singing like the gaida bagpipe": an ethnomusicological and acoustical approach

Haris Sarris
Department of Music, National Kapodistrian University of Athens, Greece
hsarris@otenet.gr

Panagiotis Tzevelekos
Department of Informatics and Telecommunications, National Kapodistrian University of Athens, Greece
taktzev@di.uoa.gr

In: K. Maimets-Volt, R. Parncutt, M. Marin & J. Ross (Eds.)
Proceedings of the third Conference on Interdisciplinary Musicology (CIM07)
Tallinn, Estonia, 15-19 August 2007, http://www-gewi.uni-graz.at/cim07/
 
(Link) pdf
 
Background in ethnomusicology
 
In the region of Thrace, as well as in the wider Balkan area, a special singing style has been observed, which is closely related to “open throat” singing techniques. This practice is often followed by low pitch sounds, produced by glottal stops, and some high pitched “screaming” tones (Rice 1977). Furthermore, the aforementioned singing techniques are strongly connected with the playing techniques of the gaida bagpipe (Levy 1985, Rice 1994, Sarris 2007), an instrument that spreads with little variations from Romania to continental Greece.
 

Visualizing Sound Emission of Elephant Vocalizations: Evidence for Two Rumble Production Types

Angela S. Stoeger, Gunner Heilmann, Matthias Zeppelzauer, André Ganswindt, Sean Hensman, and Benjamin D. Charlton
PLOS One
Published: November 14, 2012
DOI: 10.1371/journal.pone.0048907
(Link)

Abstract

Recent comparative data reveal that formant frequencies are cues to body size in animals, due to a close relationship between formant frequency spacing, vocal tract length and overall body size. Accordingly, intriguing morphological adaptations to elongate the vocal tract in order to lower formants occur in several species, with the size exaggeration hypothesis being proposed to justify most of these observations. While the elephant trunk is strongly implicated to account for the low formants of elephant rumbles, it is unknown whether elephants emit these vocalizations exclusively through the trunk, or whether the mouth is also involved in rumble production. In this study we used a sound visualization method (an acoustic camera) to record rumbles of five captive African elephants during spatial separation and subsequent bonding situations. Our results showed that the female elephants in our analysis produced two distinct types of rumble vocalizations based on vocal path differences: a nasally- and an orally-emitted rumble. Interestingly, nasal rumbles predominated during contact calling, whereas oral rumbles were mainly produced in bonding situations. In addition, nasal and oral rumbles varied considerably in their acoustic structure. In particular, the values of the first two formants reflected the estimated lengths of the vocal paths, corresponding to a vocal tract length of around 2 meters for nasal, and around 0.7 meters for oral rumbles. These results suggest that African elephants may be switching vocal paths to actively vary vocal tract length (with considerable variation in formants) according to context, and call for further research investigating the function of formant modulation in elephant vocalizations. Furthermore, by confirming the use of the elephant trunk in long distance rumble production, our findings provide an explanation for the extremely low formants in these calls, and may also indicate that formant lowering functions to increase call propagation distances in this species'.

Australian Aboriginal Musical Instruments: The Didjeridu, The Bullroarer and the Gumleaf

Neville H. Fletcher
Acoustics Australia
2003
(Link)

Abstract

The Australian Aboriginal people developed three instruments:  the didgeridu, the bullroarer, and the gum-leaf.  Most well-known is the didgeridu, a simple wooden tube blown with the lips like a trumpet, which gains its sonic flexibility from controllable resonances of the player's vocal tract.  The bullroarer is a simple wooden slat whirled in a circle on the end of a cord so that it rotates about its axis and produces a pulsating low pitched roar.  The gum-leaf, as the name suggests, is a tree leaf, held against the lips and blown so as to act as a vibrating valve with "blown-open" configuration.  Originally intended to imitate bird calls, the gum leaf can also be used to play tunes.




Musicality in human evolution, archaeology and ethnography

Iain Morley: The prehistory of music: human evolution, archaeology, and the origins of musicality.
Oxford University Press
Oxford, 2013
(Link) Oxford University Press
(Link) Amazon

Anton Killin
Biol Philos
DOI 10.1007/s10539-014-9438-y
Received: 19 February 2014 / Accepted: 21 February 2014
author contact by email:  anton.killin@vuw.ac.nz
(Link)

Abstract

This essay reviews Iain Morley’s The Prehistory of Music, an up-to-date and authoritative overview of recent research on evolution and cognition of musicality from an interdisciplinary viewpoint. Given the diversity of the project explored, integration of evidence from multiple fields is particularly pressing, required for any novel evolutionary account to be persuasive, and for the project’s continued progress. Moreover, Morley convincingly demonstrates that there is much more to understanding musicality than is supposed by some theorists. I outline Morley’s review of the archaeological and ethnographic literature, and then go on to critique his assessment of philosophical and evolutionary theories, offering some alternative perspectives that might better benefit his project.

Prelude

A prospering interdisciplinary research project has emerged over the last three decades comprising the work of a diverse array of theorists on evolution and cognition of music. This includes anthropologists, archaeologists, cognitive scientists, philosophers, musicologists, evolutionary biologists and psychologists, among others (see e.g. Bannan 2012; Wallin et al. 2000). Iain Morley’s The Prehistory of Music is a comprehensive and sophisticated outline of the present state of play by a leading authority. Morley examines recent developments in several scientific fields, and critically engages with research in philosophy and evolutionary theory. Although experts may gain little empirical insight concerning their own field, the charm of this book is in its interdisciplinary approach. Morley emphasizes connections between areas of research and links theories with potential evidential support. The text is geared seamlessly to academics, students, and general readership; its accessible style and keen exposition will no doubt garner enthusiasm for the project.

First, what is music and musicality? On Morley’s conception, very briefly, ‘music’ targets the cultural thing or set of cultural things of relevance; ‘musicality’ encompasses the biological aspects that enable the cultural thing(s) to be produced and appreciated (p. 5).1 This way of distinguishing music from musicality is not uncommon, though it is open to criticism. If the cultural and biological features of music/musicality co-evolved, attempts to artificially split them may be problematic.

As hinted above, Morley has a methodological message: understanding musicality is an interdisciplinary project. The book can also be seen as an attempt to refute the view that musicality is superfluous to understanding human nature. In other words, it is wrong to assume that music’s cross-cultural ubiquity and value have little to do with our evolved biology and psychology. Much of this takes place through chapters 5–10, which comprise an extensive overview foregrounding the complexity of music’s underlying capacities, dipping into palaeoanthropology, developmental psychology, musical cognition, neuroscience, and so on. Morley considers the evolution of hominin vocalisation and audition, relationships between music and language cognition, differences in musical cognition between trained musicians and other folk, innate versus learned musical capacities, links between vocalisation and gesture, entrainment to external pulse, whether the brain has a ‘music module’, and so on. Morley’s commentary throughout is generally very sensible and I have little critical to say about these chapters here; the text is lucid, informative and I recommend it to any interested readers. The take home message is that several ingredients of our musicality may be very old; that perhaps the biological preconditions for compound vocalisation including singing, for instance, were in place by Homo ergaster (of course this is not to claim that singing or music is so old).

However, nor is music relatively recent. I begin by summarising Morley’s discussions of archaeology and ethnomusicology (chapters 2–4). Morley argues that musical traditions predate the emergence of known Upper Palaeolithic musical instruments; given the sophistication of the latter, rightly so. Morley looks to the musics of hunter-gatherer societies ‘‘to examine and illustrate a wider diversity of the musical behaviours that exist’’ (p. 12), to survey the nature and functions of their music, their instrumentation and materials. The music of Morley’s target groups heavily relies on the voice, with mostly percussive instrumentation. This is not to give a crude ‘ethnographic analogy’, but rather to demonstrate a variety of ways of being musical with resources that might not fossilise or that require little modification.

I then turn to Morley’s critique of philosophical and evolutionary hypotheses, respectively. In chapter 10, Morley considers the work of philosopher Stephen Davies, a defender of the ‘contour theory’ of music’s expressiveness. Although Morley offers several criticisms of that view, I suspect that they miss their mark.  Moreover, Morley’s alternative is not clearly articulated. In any case, this particular focus strikes me as misplaced because Davies’ argument is contextualised in aesthetics and the art music of the West, not music or musicality broadly considered. I briefly propose a different direction for theorising about musical emotional expression that may be more fruitful for Morley’s project.

Finally, I review Morley’s take on the origin and evolution of music/musicality debate (chapter 11).  There is already an extensive evolutionary literature on musicality and its purported ‘proper’ functions. Morley does not subscribe to any novel theory of musicality’s evolution, but rather extricates oft-conflated distinctions and evolutionary pressures, painting as clear a picture of the origins and evolution of music/musicality debate as there has been. Morley espouses a five-part framework of co-evolutionary pressures which supplants some standard yet simplistic theorising about music. Yet it may not be rich enough still: I tentatively suggest that taking a niche construction perspective explicitly might provide an upgrade to the framework. Moreover, it is not yet put into action; Morley has given us the blueprint for his model, but not yet used it to test scenarios for plausibility against evidence or to support a particular theory, hybrid or otherwise.

Music archaeology

Prehistoric musical instruments and sound-producers identified by Morley include bird-bone and ivory flutes, whistles (pierced reindeer-foreleg phalanges), purported bullroarers and rasps, and various forms of struck percussion (including strikemarked lithic and bone sources). Morley argues that the earliest known musical instruments (c. 40 kya) could not represent the earliest musical traditions, contra some theorists who have focused on the purported artsy and symbolic explosion of ‘behavioural modernity’ around that time. His analysis is accompanied by extensive inventories of prehistoric instruments, a useful adjunct resource.

To date there are 104 undisputed prehistoric flutes (p. 35)—direct evidence of Upper Palaeolithic musical activity. A number of flutes revealed in the Swabian Jura range in southwestern Germany (specifically, the caves Hohle Fels, Vogelherd and Geißenkloesterle), are dated 36–40 kya (Higham et al. 2012). Most of the Swabian Jura flutes are modified bird-bone, predominantly vulture ulna and radius bones. Two swan-bone flutes were discovered in Geißenkloesterle.  Another find at Isturitz, France constitutes a large sample of around twenty bird-bone flutes. Their ages vary from 32–35 to 11–17 kya (d’Errico et al. 2003).

One of the oldest known undisputed flutes is from Holhe Fels, made from a griffon vulture (Gyps fulvus) radius, 21.8 cm long, 0.8 cm diameter. The proximal end of the bone has been manually adjusted (a V-shaped hollow area has been carved) so as to better function as a mouthpiece. The body of the flute has been scraped smooth and fingerholes inserted ‘‘by thinning the surface of the bone, creating a cratered depression in which the finger can sit and make an airtight seal, and piercing a hole in the centre of this depression’’ (p. 42). Horizontal incisions near the flute’s fingerholes suggest that measurements were made in order to position the holes (Conard et al. 2009). This may suggest that the flute was created with a pitch/scale standard in mind.

The Swabian Jura also revealed mammoth-ivory flute fragments, the oldest dated also from roughly 40 kya (p. 50). Greater skill, precision work and effort is required to produce ivory flutes (let alone acquire the raw material), so it is no surprise that there are far fewer ivory than bird-bone flutes in the archaeological record. Vulture and swan radius and ulna are naturally hollow and an appropriate size; ivory is oversized, layered, and tougher to work. To produce a flute, a section of ivory must be sawn to the correct length, it must then be sawn in half along its length, the core lamellae must be removed, and then the two halves of the flute must be refitted and bound together with a bonding substance which must create an airtight seal in order for the pipe to produce a sound. (p. 50)

Given the greater demands on working ivory into an item that is in many ways only equal to its bird-bone counterpart, Morley assumes that its use as a raw material was considered significant and valuable (p. 51). In any case it certainly bespeaks the sophistication and maturity of musical technologies at this time.

Reconstruction experiments of Swabian Jura flutes exhibit a wide range of tones and establish them as ‘‘fully developed musical instruments and not just whistles or pipes’’ (Conard and Malina 2008, p. 14). Although the oldest known, they could not have been among the very first flutes given their sophistication and design. We can safely presume that the creators and performers of these Aurignacian flutes knew what they were doing—they were not mere neophytes. The upshot: it is not plausible that 40 kya marks a transition from no musical traditions to musical traditions.

So, then, why do a fair number of flutes suddenly appear only from 40 kya? Is it due to a contingency of resources available and preservation? Or did something more significant happen? Morley conjectures that the prevalence of vulture-bone flutes ‘‘betrays a ‘special relationship’’’ between carrion birds and ancient hunters (p. 87). Moreover, Mary Stiner and colleagues have argued that avian fauna became crucial subsistence resources in the Upper Palaeolithic (Stiner et al. 2000; see also Cassoli and Tagliacozzo 1997). Vultures are large birds, common in some environments, and not threatening to prehistoric hunters. They would have provided excellent resources besides bones for musical instruments. Their bones are long, hollow, sturdy and light, so they were especially suitable raw material for flutes, and the discovery of this fact may be responsible for the sudden emergence of flutes in the archaeological record. In other words, if we are seeing a ‘revolution’ here, it is probably in the resources used (pp. 97, 323). Note that flute materials are not restricted to bone and ivory—bamboo, cane and wooden flutes appear widely in the ethnographic record, crafted from easily worked materials that are unlikely to fossilise. Flutes made from these or similar materials very plausibly could have predated bird-bone and ivory flutes and indeed co-existed with them.

Even if we discovered them, we may not recognise very early musical instruments as such. For instance, Kuhn and Stiner (1998) identify a modified ungulate bone, c. 32–35 kya, reminiscent of rasps in some traditional musical cultures, though its function as a musical artefact is speculative. (Morley argues that use-wear analysis, which has been hitherto neglected, might shed much welcome light on the presently murky status of purported rasps, bullroarers, and the like. This seems right.) Other ancient instruments may have been made from reeds, tree bark, animal skins or other ephemeral resources, as found in the ethnographic record.

There are lots of ways to be musical with natural objects that require minimal modification—consider conch shells, bison horns, hollow logs, stalactites and stalagmites (still part of musical traditions in Indonesia for example), and clapsticks of various sizes, shapes and density of wood. Furthermore, the voice is our very own in-built, natural musical instrument, and is the main focus of much traditional music. Morley reviews the ethnographic record to substantiate these suspicions and demonstrate the variety of music cross-culturally.

Music in hunter-gatherer society

Morley focuses on music in foraging societies rather than world cultures broadly construed. The mobile hunter-gatherer subsistence strategies of his target Native American, African Pygmy, Australian Aborigine, and North American Arctic groups mean that their traditional practices are not the result of agricultural lifeways. These groups occupy diverse environmental and ecological niches and their lineages are temporally as well as geographically widely displaced.

The Blackfoot and Sioux tribes of the American Plains, to briefly summarise one of Morley’s case studies, are nomadic antelope and bison hunters. Their music is monophonic song (i.e. a single melodic line) accompanied by the likes of drums, rattles, rasps and bullroarers. Music pervades their religious activities, social dancing, war dances and puberty rites (p. 17). Many songs utilise vocables rather than words. Music used in connection with symbolic activities is generally not symbolic or propositional, but rather contributes to the context emotionally (McAllester 1996). However, some songs are more symbolic: Blackfoot sun dances are thought to entreat health, wellbeing and affluence (‘Sun says to sing’, p. 18).  Others are iconic, for instance a ‘bleating calf’ song used in a characteristic Blackfoot hunting strategy (rounding up a herd at the top of a cliff face and forcing them over, leaving gravity to do the rest; Kehoe 1999). Blackfoot and Sioux instruments include rattles made from cocoons, gourds, turtle shells and deer hooves, split wooden sticks, cocoon leg- and ankle-bracelet rattles, wooden rasps, bullroarers, drums (stretched skin membrane over wooden frame), wooden and birdbone whistles, and elder-wood flutes. Very few are the kinds of artefacts likely to fossilise.

Of course, hunter-gatherer societies are not models for prehistoric Homo. The point is that, despite great variability in musical style, hunter-gatherer music is predominantly vocal, with body percussion and percussive instrumentation constructed from organic, ephemeral resources. Morley’s case studies demonstrate musical traditions and practices that we would not expect to see preserved archaeologically. Both mother-infant lullaby and group-based music feature significantly. Group-based music is typically not performed by elite specialists for a passive audience (as per Western music), but is a communal affair. Only a little melodic instrumentation is evident (e.g. flutes), which represent only small slices of the musical traditions.

Furthermore, these studies confirm that music need not always be ‘symbolic’, so there is no need to presume that it comes after symbolism and abstract thought—human characteristics thought by some theorists to have come online relatively recently, contemporaneously with ‘behavioural modernity’/‘the great leap forward’.

Our ancestors have long been competent artefact producers and users (McPherron et al. 2010). Complex javelin-like tools, for instance, appear from 400 kya (Thieme 1997). Yet many of the musical instruments described above require little modification, much less than the Upper Palaeolithic vulture radius and mammoth ivory flutes, appearing from (merely) 40 kya. Musical instruments, in other words, could be much older, representing a long tradition of resource modification that ultimately gave rise to the flutes preserved. How much older, however, remains to be argued.

Appealing to comparative ethnomusicology foregrounds an issue within music academia. Comparative studies of the world’s musical traditions shed light on the wide cultural variation of music, as well as inter- and intra-cultural similarities and the prospects for discovering universals. Since the second half of the twentieth century, however, ethnomusicologists have tended to focus on musical analysis in terms of political, social, cultural, economic, or gender theories, poststructuralism and postmodernism, power relations, pedagogy, and theories of meaning. Morley’s interests add weight to the call for a return to the comparative study of traditional musics (see e.g. Savage and Brown 2013; Traˆn Quang and Bannan 2012).

[The remainder of this paper discusses "music, emotion and expressivity" and the "origins and evolution of music/expressivity".]