Grantee Spotlight: Jamie Clark

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ClarkLeakey

Jamie Clark works on fauna from Mughr el-Hamamah (Jordan) in the Zooarchaeology Lab at the University of Alaska Fairbanks.

Jamie Clark (University of Alaska Fairbanks) was awarded a Leakey Foundation Research Grant during our fall 2015 cycle for her project entitled “Early Upper Paleolithic hunting strategies at Mughr el-Hamamah, Jordan.”

Understanding the reasons behind the success and spread of our species (Homo sapiens sapiens) relative to archaic humans such as the Neanderthals is a major focus of research within paleoanthropology.  A significant amount of research has centered on the Levant due to its potential as a corridor for population expansion out of Africa. Not only does the region preserve a number of sites associated with the Early Upper Paleolithic (EUP; presumably produced by modern humans), but it also preserves a rich record of Neanderthal occupation. The site of Mughr el-Hamamah (MHM, Jordan) is one of only a few sites in the southern Levant that both dates to the initial stages of the Early Upper Paleolithic (EUP; 45-39 ka cal BP) and has extensive faunal preservation. The site thus offers a unique opportunity to explore questions relating to human subsistence and landscape use during a critical period in the later expansion of our species from Africa into Eurasia.

Serial sampling a gazelle molar for stable isotope analysis. Photo courtesy Gideon Hartman.

Our project has two primary components: zooarchaeological analysis (to be conducted by Jamie Clark) and isotopic analysis (to be conducted by Gideon Hartman, co-PI). Zooarchaeological work will focus on the analysis of the large assemblage of identifiable bones (~11,000 specimens). Stable isotope work will focus on the analysis of carbon and oxygen isotopic data deriving from the tooth enamel from two key prey species: gazelle and fallow deer. We will combine these datasets in order to address three distinct issues: First, to explore the hypothesis that EUP populations had a wider diet breadth than their Middle Paleolithic (MP) counterparts. Second, to reconstruct environmental conditions in the eastern Jordan Valley. Finally, we will develop a model of landscape use and subsistence strategies that will provide a baseline for comparison with site that pre- and post-date the EUP, allowing for new insights into variation in the adaptive strategies of MP and UP populations in the region.

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Photograph of the Early Upper Paleolithic site of Mughr el-Hamamah (the site is the second cave from the left). Photo courtesy of Aaron Stutz.

From the Field: Alia Gurtov

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Alia Gurtov, MNI analysis, National Museum of Dar es Salaam, Tanzania

Alia Gurtov, MNI analysis, National Museum of Dar es Salaam, Tanzania

Here we have another update from fall 2014 grantee Aliz Gurtov. To read a summary of her work, please click here, and to read her first update from the field, click here

With the start of 2016, it is time for a progress update. As I write, I am sitting in a pleasantly overheated café while Madison, WI, withers in 5° F temperatures. This couldn’t feel more different from the conditions in which I first wrote about my research.

This disconnect is not simply climatic. As I’ve been told by many wise academics, the research road is bumpy. I left off the previous update with great excitement to scan my dental casts in Nashville, TN, in August 2015. When I finally placed my first cast under the confocal microscope, however, I could see that something was wrong. There were microscopic bubbles in the surface that I could not account for by any natural process. I rapidly scanned a dozen teeth, finding only a few casts of sufficient quality. What a disaster. I continued to scan teeth for the next few days, confirming that a good portion of my sample had some kind of molding or casting error that was not present in the casts I’d analyzed back in February, or those I’d analyzed for my pilot study.

Upon returning to Madison, I set about recasting my molds using several different curing methods and epoxy component ratios. I called several epoxy manufacturing companies, dental microwear experts, and students with extensive casting experience, but gained little insight into the source of my particular bubbly blight. Because all of the original teeth are housed in the National Museum of Tanzania, I was unable to try remolding them, though this is the next logical step. I then sent a sample of re-casted teeth to my collaborator, Professor DeSantis at Vanderbilt University, to check before I scheduled another week with the confocal. But after two weeks it became apparent that while the parcel was recorded as delivered, it had never reached the department office. With no alternative, and only one week when the confocal would be available, I booked another flight to Nashville.

And once again, most of my casts were unusable. I don’t think my heart has ever plunged so rapidly into my stomach before. Nevertheless, I stuck with the microscopy for the next few days and managed to find a sufficient number of usable teeth from which to draw pristine microwear surfaces. I am still devastated by the number of worthless casts in my sample, but I have learned to compartmentalize!

Now, while I drink this cappuccino, I am looking at a modest but sufficiently populated spreadsheet of dental microwear analyses from such extinct bovid species as Parmularius altidens and Antidorcas recki. Being the most abundant bovids at my primary sites of FLK North and FLK Zinj, I am grateful to have them. As my pilot study suggests, some of these microwear variables distinguish between wet and dry season deaths and, by extension, seasons of hominin and carnivore meat-foraging activity. By comparing the bovid microwear values between anthropogenic FLK Zinj and carnivore-generated FLK North, I will be able to determine if hominins were meat-foraging during seasons of peak or low carnivore activity around watering holes, or employing no seasonal meat-foraging strategy at all. Thus far, there appears to be almost perfect overlap in the foraging season of Antidorcas recki, a small gazelle about the size of a modern Thomson’s and likely prey of ancient leopards. I now turn to Parmularius altidens to see what this larger bovid says about hominin foraging seasonality at Olduvai Gorge.

To hear about my final results, please join me for my podium session on Saturday afternoon, April 16th, at the AAPA meetings in Atlanta.

We look forward to seeing Alia at AAPA, and we hope to report on her findings!

 

Grantee Spotlight: Timothy Campbell

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Timothy Campbell, PhD candidate at Texas A&M, was awarded a Leakey Foundation Research Grant during our fall 2015 cycle for his project entitled “Paleoenvironmental reconstruction of Sterkfontein and Swartkrans using rodent postcrania.”

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Simon Mataro (left) and Tim Campbell (right) after finding modern micromammal remains under an active owl roost in Laetoli, Tanzania

Many theories of hominin behavioral and morphological evolution have focused on the environments occupied by early members of our lineage in order to provide an adaptive context for major evolutionary events. One way in which past environments are inferred is through analyses of the fossilized fauna found at sites. In many of these studies researchers will either study recovered fossilized cranial and dental remains in order to reconstruct past faunal community composition or study the postcranial remains of larger taxa within an ecological functional framework. While studies of craniodental remains from smaller taxa, such as rodents, have also contributed to our understanding of the past, analyses of their postcrania have lagged behind those of other groups such as African antelopes.

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Simon Mataro (left) and Tim Campbell (right) recovering modern micromammal remains under an active owl roost in Laetoli, Tanzania

As such, my study will assess whether analyses of African rodent postcrania can provide useful data for paleoecological and paleoenvironmental reconstructions. First, I will test if modern rodent postcrania can be used to identify what genus and species are present, and if they can be used to reconstruct past rodent faunal community composition. Second, I will test if modern rodent postcrania can be analyzed within an ecological functional framework to reconstruct past environmental conditions. The correspondence in environmental signals obtained between these two approaches will then be assessed. After compiling a modern comparative dataset I will then analyze the rodent fossilized rodent postcrania from the hominin-bearing sites of Sterkfontein and Swartkrans in duel taxonomic and ecological functional based analyses in order to test previously proposed signals utilizing other proxy data, including rodent craniodental remains. In conclusion this study will improve our ability to reconstruct past environments associated with early hominin remains through analyses of a currently underutilized source of data, rodent postcrania, and will help clarify the environmental context at two sites important to our understanding of human evolution.

Modern Gerbilliscus leucogaster (USNM-295430) postcrania from the Smithsonian National Museum of Natural History

Grantee Spotlight: Kaitlin Wellens

Kaitlin Wellens

The next grantee from our fall 2015 cycle is Kaitlin Wellens, PhD candidate from The George Washington University. She was awarded a grant for her project entitled “Maternal effects on juvenile chimpanzee social behavior and physiological stress.”

Kaitlin Wellens

Kaitlin Wellens

Mothers can have a tremendous impact on various aspects of their offspring’s early development, including behavior, stress responses, cognition, and even gene expression.  While the importance of mothers on infant development has been studied in various species, less is known about how mothers influence their offspring post weaning.  The question of maternal effects beyond infancy is particularly interesting when considering human and nonhuman primates, as both experience extended periods of development and thus close associations with mothers long after infancy.  Juvenescence, the period between nutritional independence and sexual maturation, may be especially important, as it is hypothesized to be an influential period of social development in primates.

DSC03443In order to address this gap, I am integrating extensive behavioral, physiological, and demographic data from the wild chimpanzees at Gombe National Park, Tanzania to investigate how chimpanzee mothers influence their juvenile offspring’s social behavior and associated stress responses.  Specifically, I am exploring how early maternal attachment, maternal rank, and maternal proximity relate to how frequently and with whom juveniles socialize with as well as the stress levels associated with these social interactions.  By conducting this study in chimpanzees, one of our closest living relatives, I hope to shed an important comparative light on the evolution of an extended association with mothers and how this influences social development.

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Book Shelf: The Strange Case of the Rickety Cossack

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23014618by Kilbee Brittain

A new book by Ian Tattersall is always a cause for celebration, and The Strange Case of the Rickety Cossack is no exception – with a warning:

It’s a demanding story of old bones, their finders and keepers, their interpreters slugging it out over taxonomy and ultimate meaning. Not a book for an afternoon at the beach, but one to cherish and chat about with good friends who enjoy a challenge. Here are a few highlights:

A Rickety Cossack

The quirky title refers to the strange interpretation of some bones found in the Feldhofer Grotto in Germany’s Neander Tal (Valley) in 1856 by miners looking for lime to fuel the booming chemical industry.  An alert supervisor saw bones in the rubble workmen were dumping over a cliff.  The cache was shown to a teacher, who correctly identified them as ancient.  They were passed along to a respected Bonn anatomist, Hermann Schaffhausen, who concluded they were from a barbarous race of Homo sapiens.

The bones were passed on to pathologist Rudolf Virchow, who diagnosed the fossil as having suffered rickets as a youth, the pain being intensified by his life on horseback, which agony caused him to furrow his brow constantly, his perpetual frown causing his bony ridge across his brow.  Fellow Bonn faculty member August Franz Mayer concluded that the fossil had been a Cossack soldier in the Russian army rampaging across Germany in 1814 en route France, and, being wounded, crawled into the Feldhofer cave to die.

Darwin’s good friend Thomas Huxley had a good time mocking this “absurd story,” but did not see the bones as being ancient.  But geologist William King announced at a scientific meeting in 1863 that the forehead configuration of the Feldhofer skull represented a distinct human species, Homo neanderthalensis.  King’s prescient analysis was almost immediately substantiated by George Busk’s announcement of a Gibraltar cranium with similar features.  But public acceptance of this new human species would take more discoveries over the next 20 years.

As more bones were found, 19th-century Britain was in intellectual turmoil over humans’ place in nature, with the biblical idea of man as the ultimate creation.  Larger-than-life men stated their views.  Alfred Russel Wallace, returned from his strenuous years in Amazonia (including being shipwrecked on the way home and losing all his specimens), left for 7 years in Malaysia, returning with his manuscript proposing “natural selection” as the means of the appearance of new species.  He sent the manuscript to his friend Charles Darwin, who had independently formed the same idea on his 5-year trip around the world, and was at work on his magnum opus, The Origin of Species.  Darwin was deeply upset at the prospect of being scooped.  Huxley set up a debate for Darwin and Wallace at the Linnaean Society.

The resulting ideas, including Darwin’s observation that the African apes and humans certainly shared some similar traits, went “viral”.  The oft-quoted horrified exclamation of the wife of the Bishop of Winchester sums up the Victorian view:  “Descended from the apes!  My Dear, let us hope that it is not true, but if it is, let us pray it will not become generally known.”

1950

The year 1950 is Tattersall’s choice as “the most momentous in the 20th-century intellectual history of paleoanthropology.”  The names Mayr, Sherwood Washburn, Clark Howell are familiar to the fans of the subject.

The invention of radiocarbon dating was another gift of 1950, invented by University of Chicago physical chemist William F. Libby, a scientific way of dating fossils to about 40,000 to 50,000 years ago, by measuring the decay of “C” in a sample.  The method was used in dating the rock shelter at Les Eyzies in SW France, where sediments revealed a succession of cultures, including “the art-drenched Magdalenian culture.”

“In the post-1950 anthropological milieu strode Louis Leakey,” Tattersall writes.  Kenya-born British archaeologist and anthropologist and his wife Mary, also an archaeologist, had been searching East African hills and vales for decades, for signs of early hominids.  They had recently concentrated on Olduvai Gorge in northern Tanzania.  In 1959 at Olduvai’s lower level of its “layer cake” of time amidst scattered stone tools, Mary found a magnificently preserved cranium (skullcap without mandible, or, lower jaw), with huge molars.  Leakey called it Nutcracker Man, a new species, Zinjanthropus boisie.  “This weather-beaten, White African couple” had the support of the National Geographic Society, which poured funds into the Leakeys’ work, understanding its importance and sensing a dynamic, continuing story.  Soon after, the Leakeys found Zinj’s missing mandible, which they thought made the skull complete and “a new and truly primitive ancestor of Homo”.  Louis had a candidate for Earliest Toolmaker!

By using the new potassium argon (K/Ar) dating method on the fossil remains and volcanic ash, a date of about 1.75 million years was determined.

Goodall

Tattersall makes no mention of Jane Goodall in his text or even in the index. Not even in his chapters on the Leakey family.  Goodall is celebrating her 55th year of the chimpanzee project at Gombe Steam National Park in Tanzania.  Dr. Leakey suggested the study as a project for Goodall when she asked his advice soon after her arrival from Great Britain in 1957.  She went to the forest, taking only a native cook and her own mother.  Soon she had assembled a small staff and had attracted the attention of the National Geographic, which has featured her work there in numerous articles.  Among her many scholarly findings, one stands out as most revolutionary; On November 4, 1960, she watched a male chimp (whom she had named David Greybeard) pick an 18-inch long grass stem, pluck leaves to make the stem smooth, and insert it carefully into one of the winding tunnels of a nearby termite mound, then withdraw it, all covered with termites, and swipe it through his lips to chew up the crunchy insects.  He did this numerous times.  On subsequent days she saw the same behavior, and cabled Leakey, who cabled back, “Now we must redefine ‘tool’, redefine ‘man’, or accept chimpanzees as human”.

Leakey Vessels

Tattersall urges readers to remember “that closely-related species like Homo Neanderthalensis and Homo sapiens are “very leaky vessels”, but that “no biologically meaningful melding” occurred.  Homo Neanderthalensis “retained its morphological identity until it disappeared.”

Our species is extremely young, a short 200,000 years old, with most of our history since we left Africa about 60,000 years ago…  We have discarded the idea of human “races” as we have become so mobile (and must guard against its reinstatement).  We recognize certain biological markers, and understand that skin color can be a genetic reaction to climate.

In the last 10,000 years, at the end of the last Ice Age, human population has mushroomed and spread, our only barriers now being cultural.  But we are not an exception to Nature’s rules “We are the pinnacle of nothing, simply one more twig on what was until very recently a luxuriant evolutionary tree…” (p. 222).

Tattersall tells of his first time in Madagascar and the Comores, studying the beautiful and varied lemurs.  He writes of their diversity, their beauty, their adaptability:  Noting the diversity in their more than 50 species, he notes that it is not unusual among successful groups of mammals.  They have been surviving, diversifying all these millennia, evolving as their very special kind of primate, adapting to climate changes and the environmental destructiveness of their only competitors, who arrived on their island just about one thousand years ago.

Tattersall closes his elegantly detailed study by encouraging humans to take note of our imperfect selves as being no exception to Nature’s rules, like our primate kin, the lemurs.  “Odd we may be,” the author admits, “but we are nonetheless an odd primate.”

Bravo Ian Tattersall, for putting us in our place with erudition, flair, and in such good company!

Kilbee Brittain received her BA from Stanford University and her PhD from University of California Los Angeles. For decades, she has been actively engaged with the docent program at the Los Angles Zoo and has been am enthusiastic supporter of The Leakey Foundation for 31 years.

Click here to read the full article by Kilbee Brittain.