Archaeozoology

Research published in this week’s Science journal shows that some of our closest extinct relatives had more in common with gorillas than previously thought. Dr Charles Lockwood, UCL Department of Anthropology and lead author of the study, said: “When we examined fossils from 1.5 to 2 million years ago we found that in one of our close relatives the males continued to grow well into adulthood, just as they do in gorillas. This resulted in a much bigger size difference between males and females than we see today.

“It’s common knowledge that boys mature later than girls, but in humans the difference is actually much less marked than in some other primates. Male gorillas continue to grow long after their wisdom teeth have come through, and they don’t reach what is referred to as dominant “silverback” status until many years after the females have already started to have offspring. Our research makes us think that, in this fossil species, one older male was probably dominant in a troop of females. This situation was risky for the males and they suffered high rates of predation as a result of both their social structure and pattern of growth.”

The research used 35 fossilised specimens of Paranthropus robustus, an extinct relative of Homo sapiens which existed almost two million years ago. The fossils came from the palaeontological sites of Swartkrans, Drimolen and Kromdraii, all of which are in South Africa’s Cradle of Humankind World Heritage Site near Johannesburg.

The research was inspired by earlier discoveries at Drimolen by Dr Andre Keyser, one of the co-authors of the study. Dr Colin Menter, from the University of Johannesburg and co-director of current fieldwork at Drimolen, explains: “Discoveries at this site showed us that sex differences in Paranthropus robustus were greater than we had previously thought. While there are some specimens from Drimolen that are just as large and robust as those from other sites like Swartkrans, there is a complete female skull that is distinctly smaller than the other, well-preserved specimens of the species.”

Jacopo Moggi-Cecchi, based at the University of Florence and an expert on fossil teeth, participated in the study and says: “It takes large samples of fossils to ask questions about variation and growth, and it’s really a tribute to fieldworkers such as Robert Broom and Bob Brain [who worked at Swartkrans] that this research could even take place. It’s also an example of why we need to continue to look for fossils after we think we know what a species is – more specimens allow us to answer more interesting questions. Even isolated teeth can give us new insights into what variation means.”

Dr Lockwood adds: “The pattern of growth also gives a better understanding of who is male and who is female in this sample of skulls and it turns out that there are far more males in the fossil sample. Because fossils from the most prolific site, Swartkrans, are thought to have been deposited by predators such as leopards and hyenas, it appears that males were getting killed more often than females.”

Basically, males had a high-risk, high-return lifestyle in this species. They most likely left their birth groups at about the time they reached maturity, and it was a long time before they were mature enough to attract females and establish a new group. Some of them were killed by predators before they got the chance.”

A final point made by the researchers is that not all fossil hominin samples show the same patterns, and it is quite possible that further work will reveal clear diversity in social structure between human ancestors, in the same way that one sees differences among apes such as chimpanzees, bonobos, gorillas, and orangutans. This research will help us to understand how human social structure evolved.

Source: EurekAlert!

It was not the isolation of the Ice Age that determined the genetic distribution of bears, as has long been thought. This is shown by an international research team led from Uppsala University in Sweden in the latest issue of Molecular Ecology. One possible interpretation is that the hunting of bears by humans and human land use have been crucial factors.

Twenty thousand years ago Europe was covered by ice down to Germany, and the climate in the rest of Europe was such that several species were confined to the southern regions, like the Iberian Peninsula and Italy. These regions were refuges, areas where species could survive during cold periods and then re-colonize central and northern Europe when it got warmer. But the brown bear was not limited to these regions, ­it could roam freely across major parts of southern and central Europe. The current study analysed mitochondria from bear remains. Some of the fossils are 20,000 years old. The analysis shows that the genetic pattern in these ancient brown bears differed from that of bears living today.

“Previously today’s genetic structure was interpreted as showing that the brown bear was isolated in southern Europe, just like many other species. But our study shows that this was not the case,” says Love Dalén, one of the Swedes participating in the study.

The new findings show instead that the brown bear survived in central Europe, even during the coldest period of the Ice Age. The scientists now believe that the genetic pattern found in today’s brown bears is the result of historical hunting and of human activities in the brown bear’s natural environment. A few thousand years ago, there were brown bears all over Europe, while today there are just a few remaining populations in Spain, Italy, the Balkans, and Scandinavia.

“It’s not strange that findings were interpreted differently in the past, with the brown bear extinct in most of its old area of inhabitation. We only had the remnant populations to work with,” says Anders Götherstam, who directed the study.

Source: EurekAlert!

The gigantic fossil claw of an 390 million-year-old sea scorpion, recently found in Germany, shows that ancient arthropods — spiders, insects, crabs and the like — were surprisingly larger than their modern-day counterparts.

“Imagine an eight-foot-long scorpion,” said O. Erik Tetlie, postdoctoral associate in the Department of Geology and Geophysics at Yale, and an author of the report online in Royal Society Biology Letters. “The claw itself is a foot-and-a-half long — indicating that these ancient arthropods were much larger than previous estimates — and certainly the largest seen to date.”

Colleague and co-author Markus Poschmann discovered the fossil claw from this ancient sea scorpion, Jaekelopterus rhenaniae, in a quarry near Prüm in Germany. This creature, which lived between 460 and 255 million years ago is of a group that have been known for some time to be among the largest extinct arthropods, based on both body fossils and trace fossils. According to the authors, it is believed that these extinct aquatic creatures are the ancestors of modern scorpions and spiders.

Tetlie said that geologists are debating the reasons for evolution of these giant arthropods, “While some believe they evolved with the higher levels of atmospheric oxygen that were present in the past, some say they evolved in a parallel ‘arms race’ with early armoured fish that were their likely prey.” he said.

Lead author Simon Braddy from the Department of Earth Sciences at the University of Bristol, UK said, “This is an amazing discovery. We have known for some time that the fossil record yields monster millipedes, super-sized scorpions, colossal cockroaches, and jumbo dragonflies, but we never realised, until now, just how big some of these ancient creepy-crawlies were.”

Source: EurekAlert!

Jim Lemire of From Archaea to Zeaxanthol is the host of the 93rd edition of the Tangled Bank, and an interesting edition it is too. Those contributions I found particularly intriguing included John at a DC Birding Blog’s discussion about what claws can tell us about bird evolution, and Coturnix’s description of the extreme dinosaur Nigersaurus. There’s plenty there for all though so go and read.

It’s carnival time again, and Carl Feagans at Hot Cup of Joe has assembled the best and brightest from the world of anthropology and archaeology for the 28th edition of Four Stone Hearth. Editor’s Choice this week is ‘Bringing archaeology into forensics’ by Anatoly Venovcev of Cosmpolitan, and I have to agree that it is a fascinating article. There is plenty more there too though so do wander over and take a look.

The earliest known use of cacao –– the source of our modern day chocolate –– has been pushed back more than 500 years, to somewhere between 1400 and 1100 B.C.E., thanks to new chemical analyses of residues extracted from pottery excavated at an archaeological site at Puerto Escondido in Honduras. The new evidence also indicates that, long before the flavour of the cacao seed (or bean) became popular, it was the sweet pulp of the chocolate fruit, used in making a fermented (5% alcohol) beverage, which first drew attention to the plant in the Americas.

For more details, see the full release at the University of Pennsylvania Museum of Anthropology and Archaeology website.

The flood believed to be behind the Noah’s Ark myth kick-started European agriculture, according to new research by the Universities of Exeter, UK and Wollongong, Australia. Published in the journal Quaternary Science Reviews, the research paper assesses the impact of the collapse of the North American (Laurentide) Ice Sheet, 8000 years ago. The results indicate a catastrophic rise in global sea level led to the flooding of the Black Sea and drove dramatic social change across Europe. The research team argues that, in the face of rising sea levels driven by contemporary climate change, we can learn important lessons from the past.

The collapse of the Laurentide Ice Sheet released a deluge of water that increased global sea levels by up to 1.4 metres and caused the largest North Atlantic freshwater pulse of the last 100,000 years. Before this time, a ridge across the Bosporus Strait dammed the Mediterranean and kept the Black Sea as a freshwater lake. With the rise in sea level, the Bosporus Strait was breached, flooding the Black Sea. This event is now widely believed to be behind the various folk myths that led to the biblical Noah’s Ark story. Archaeological records show that around this time there was a sudden expansion of farming and pottery production across Europe, marking the end of the Mesolithic hunter-gatherer era and the start of the Neolithic. The link between rising sea levels and such massive social change has previously been unclear.

The researchers created reconstructions of the Mediterranean and Black Sea shoreline before and after the rise in sea levels. They estimated that nearly 73,000 square km of land was lost to the sea over a period of 34 years. Based on our knowledge of historical population levels, this could have led to the displacement of 145,000 people. Archaeological evidence shows that communities in southeast Europe were already practising early farming techniques and pottery production before the Flood. With the catastrophic rise in water levels it appears they moved west, taking their culture into areas inhabited by hunter-gatherer communities.

Professor Chris Turney of the University of Exeter, lead author of the paper, said: “People living in what is now southeast Europe must have felt as though the whole world had flooded. This could well have been the origin of the Noah’s Ark story. Entire coastal communities must have been displaced, forcing people to migrate in their thousands. As these agricultural communities moved west, they would have taken farming with them across Europe. It was a revolutionary time.”

The rise in global sea levels 8000 years ago is in-line with current estimates for the end of the 21st century. Professor Chris Turney continued: “This research shows how rising sea levels can cause massive social change. 8,000 years on, are we any better placed to deal with rising sea levels” The latest estimates suggest that by AD 2050, millions of people will be displaced each year by rising sea levels. For those people living in coastal communities, the omen isn’t good.”

Source: EurekAlert!

Chimpanzees crave roots and tubers even when food is plentiful above ground, according to a new study that raises questions about the relative importance of meat for brain evolution. Appearing online in the early edition of the Proceedings of the National Academy of Sciences, the study documents a novel use of tools by chimps to dig for tubers and roots in the savanna woodlands of western Tanzania.

The chimps’ eagerness for buried treats offers new insights in an ongoing debate about the role of meat versus potato-like foods in the diet of our hominid ancestors, said first author Adriana Hernandez-Aguilar, who collected the field data for her doctoral research at the University of Southern California. The debate centers on the diet followed by early hominids as their brain and body size slowly increased towards a human level. Was it meat-and-potatoes, or potatoes-and-meat?

“Some researchers have suggested that what made us human was actually the tubers,” Hernandez-Aguilar said.

Anthropologists had speculated that roots and tubers were mere fallback foods for hominids trying to survive the harsh dry season in the savanna 3.5 million years ago and later (hominids are known to have consumed meat at least as early as 2.5 million years ago). But the study found that modern chimps only dig for roots during the rainy season, when other food sources abound. The finding suggests, but does not prove, that hominids behaved the same way. Researchers view modern chimps as proxies for hominids because of similarities in habitat, brain mass and body size.

“We look at chimps for the way that we could have behaved when our ancestors were chimp-like,” Hernandez-Aguilar said.

Corresponding author Travis Pickering, of the University of Wisconsin-Madison, said: “Savanna chimps, we would contend, are dealing with environmental constraints and problems – evolutionary pressures – that our earliest relatives would have dealt with as well.”

The tuber-digging chimps “suggest that underground resources were within reach of our ancestors,” added co-author James Moore of the University of California at San Diego.

The study was based on observation of 11 digging sites in the Ugalla savanna woodland of western Tanzania. Chimpanzees were linked to the excavated tubers and roots through knuckle prints, faeces, and spit-out wads of fibers from those underground foods. Seven tools were found at three of the sites, with worn edges and dirt marking implying their use as digging implements.Because chimpanzees in the area are not habituated to humans, Hernandez-Aguilar was unable to observe them directly. She plans to conduct further observations in the area and to advocate for greater protection for the savanna chimps.

“Chimpanzees in savannas have not been considered a priority in conservation plans because they live in low densities compared to chimps in forests,” she said. “We hope that discoveries such as this will show the value of conserving the savanna populations.”

Source: EurekAlert!

The Late Antique Period in Egypt (AD 330 - 642) is well documented through Greek and Coptic papyri, parchment and ostraca. While the Greek texts mainly describe the propertied classes, those of the Coptic period comprise Christian writings, many of which relate to monasticism. During the 4th to 5th centuries AD, numerous monasteries were constructed in the desert, close to the Nile valley.

Coptic literature suggests that animal products were not common items in the daily diet of Egyptian monks. Meat, fish, cheese and eggs were restricted foods, so much so that only sick monks were allowed them, and this has led to the assumption that monastic fare was mainly vegetarian. This has led in turn to the assumption by papyrologists that terms such as garum and taricheion, which elsewhere would refer to ‘fish sauce’ and ‘pickled fish’ respectively, refer in monastic contexts to other preserved comestibles such as pickled herbs or vegetables. However, this was challenged in 2002 by Clackson, who observes that dried and salted fish were found during excavation at the monastery of Bawit. Moreover, some monasteries own herds of cattle and flocks of sheep and goats, yet again animal products are overlooked by default.

The site of Kom el-Nana is situated 304km south of Cairo on the east bank of the Nile at the southern edge of Tell el-Amarna. The site has been dated to the Late Antique Period (AD 425/50 - 650) via coinage and pottery, and identified as a monastery through three ostraca and graffiti. The pharaonic site of Tell el-Amarna, on the other hand, was only occupied for twenty years (c. BC 1350), and thus provides a unique and valuable insight into the workings of a New Kingdom city.

Much of the Kom el-Nana mammal bone is heavily fragmented and was recovered from alley and floor deposits, as opposed to the middens which contained most of the bird and fish bone. Clearly the monastic community had consumed beef, pork and ovicaprid flesh, but in what quantities was impossible to ascertain. Dog and donkey remains show no signs of butchery and most likely constitute a pet/scavenger and a beast of burden respectively. There is no evidence for the hunting of wild mammals.

By virtue of carcass size, beef was pre-eminent at Tell el-Amarna, although pork and ovicaprid flesh were important dietary items. The workman’s village assemblage from Tell el-Amarna is dominated by pig bones; indeed, pig and goat bones outweigh those of cattle. The villagers diet was supplemented by wild beasts.

Despite the sparseness of the monastic avian bone, it is evident that the community ate chicken, pigeons, and doves. It is not known whether pigeons were domesticated but it seems likely since cotes were commonly used during the Graeco-Roman period.The occasional duck and quail were also consumed. The bird bones recovered from the Pharaonic sites, on the other hand, are mainly those of winter-visiting waterfowl: great cormorant, teal, mallard, European coot, white-fronted goose, and greylag goose. The greylag goose may have been domesticated, but no eggshell of domestic birds has so far been found in the Pharaonic Period. Indeed, in contrast to the monastery, there is no evidence for any domesticated birds.

Shellfish were eaten at Kom el-Nana, but it is difficult to assess their importance on other sites due to insufficient sampling. Fish was also clearly an important dietary item; the preponderance of fish remains in the monastic assemblage is striking. There are distinct differences in the consumption of fish between the Pharaonic and Late Antique Periods at Tell el-Amarna and Kom el-Nana respectively. Schall was the main fish eaten by the monks following Bagrus, but although the Ancient Egyptians consumed schall, they also consumed greater numbers of more palatable fish, such as the Alestiidae, Tilapiini, Clarias, mormyrids and mugilids. Floodplain fishing was more predominant in the Late Antique Period as evidenced by the occurrence of very small schall.

Reference: Luff, R.M. 2007. Monastic diet in Late Antique Egypt: zooarchaeological finds from Kom el-Nana and Tell el-Amarna, Middle Egypt. Environmental Archaeology 12 (2): 161-174

See also: ‘Butchery - Variation through Time and Space‘ for more about Tell el-Amarna.

Osteomalacia, literally softening of the bones, is a metabolic disorder of the adult skeleton that is usually defined in terms of its major causes: deficiency of phophorus or vitamin D. Osteomalacia is characterised by accumulation of excess, unmineralised and presumably unmineralisable osteoid on trabecular surfaces. Osteomalacic bones have a diminished resistance to pressures and tensions, and increased susceptibility to the stresses and strains of ordinary activity. As a result, there is excess deposition of matrix where mechanical stimuli are strongest, such as at insertions of tendons and fascia, places of angulation and curvature, and on stress-oriented epiphyseal trabeculae. When the disease is advanced, bones break easily, the marrow cavity is enlarged and the cortex is thin, spongy and soft. Deformities are often present.

Osteomalacia due to deficiency of phosphorus is uncommon in animals except in areas of the world, such as South Africa, northern Australia and the North Island of New Zealand, where the pasture is low in phosphorus and supplemental feeding is rare. Cattle are more susceptible than sheep, and horses seem to be remarkably resistant to phosphorus deficiency. Osteomalacia due to vitamin D deficiency occurs in grazing animals where the combination of relatively high latitudes and relatively mild climates allow them to be pastured for much of the year. Critical factors are probably the unavailability of sun-cured hay, the demands of pregnancy and lactation, and inadequate exposure to ultraviolet light.

Whereas osteomalacia is a disease of mature bones, rickets is a disease of growing bones. The causes and pathogenesis are the same, but the vitality of youthful tissue and the transformations and vulnerability of growing bone introduce greater complexity into the morphogenesis of rickets. Since bones mature at different times, the two diseases may co-exist in a skeleton.

There is still controversy about the respective role of vitamin D, calcium and phophorus in the aetiology of rickets. The basic question is where vitamin D prevents rickets solely by increasing blood calcium or whether it also changes the matrix (osteoid or cartilage) so it can accept mineral. The fact that uncomplicated calcium deficiency does not produce rickets is inconclusive because only in the terminal stages of this deficiency does severe hypocalcaemia occur, at which time growth slows, obviating the development of rickets.

Enlargement of joints is a typical sign of rickets. It involves long bones and is usually accompanied by lateral or medial deviation. The enlargement is partly due to the flaring of the metaphysis and partly to retarded longitudinal growth of the epiphysis and its flattening by weight bearing. Normally, the growth of bone at the physis is followed by subperiosteal resorption at the metaphysis. In rickets, osteoid (and unmineralised cartilage) persists in the metaphysis and modelling of the shaft fails because the osteoid is resistant to resorption. This results in the club-like thickening in the metaphyseal region known as rachitic metaphysis; it is most prominent at the costochondral junctions where the row of beaded metaphyses is called the rachitic rosary.

In humans, the squat bow-legged figure is not so familiar in European countries as they were 100 years ago. Evidence has been found in Neolithic skeletons from Denmark and Norway, and more plentiful evidence comes from Hungary in the Roman period. However, rhe rarity of this disease in the past is attested by the few cases described even in exhaustive studies of human remains prior to the Medieval period. Urbanisation and the later industrial revolution in cities with their crowded housing and industrial smoke created this ‘disease of civilisation’. Rickets was a common disease in England in the 17th and 18th centuries (’The English Disease’) and Madonna and Child paintings produced in the Netherlands in the 15th and 16th centuries show characteristic deformities in the form of bowed legs and deformed chests. It was described in 17th century England as a new disease, which does support the lack of evidence before that time in the British archaeological record. Today it may be seen in Asian women in western countries where clothing covers most of their skin (and they may not consume enough vitamin D), but anybody who is housebound and not exposing their skin to the sun is susceptible.

References:

Jubb, K. V. F., Kennedy, P. C., and Palmer, N. 1993. Pathology of Domestic Animals. 4th Edition. Volumes 1, 2 and 3. London: Academic Press.

Roberts, C. and Manchester, K. 2005. The Archaeology of Disease. 3rd Edition. Stroud: Alan Sutton Publishing Ltd.