Oldest Hominin DNA Sequenced: Mitochondrial Genome of a 400,000-Year-Old Hominin from Spain Decoded
Dec. 4, 2013 — Using novel techniques to extract and study ancient DNA researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, have determined an almost complete mitochondrial genome sequence of a 400,000-year-old representative of the genus Homo from Sima de los Huesos, a unique cave site in Northern Spain, and found that it is related to the mitochondrial genome of Denisovans, extinct relatives of Neandertals in Asia. DNA this old has until recently been retrieved only from the permafrost.
Early Tree-Dwelling Bipedal Human Ancestor Was Similar to Ancient Apes and ‘Lucy’ but Not Living Apes
Dec. 4, 2013 — An analysis of the femur of one of the oldest human ancestors reveals the six-million-year-old “Millenium Man” was bipedal but lived in the trees. The research, led by Stony Brook University researchers and their team of international paleoanthropologists, could provide additional insight to the origins of human bipedalism and is published inNature Communications.
“As scientists work to identify and catalog the now more than 800 hominid fossils recovered on the Rising Star Expedition, they pull from a body of knowledge accumulated over decades in their field.
An intimate knowledge not only of broad principles but of specific specimens around the world is their constant reference as each piece is brought to the tent marked “SCIENCE.”
While it’s entirely possible that somewhere in the cave below, hidden under dirt and other bones lies a perfectly intact skull, so far the the team is working with pieces brought up individually and carefully fitted together by Peter Schmid, an expert in reconstructions who gave Lucy her more accurate reassembly in the 1980s.
Peter was aided in his skull work last week by Darryl de Ruiter of Texas A&M University, who carefully examined every skull fragment and individual tooth in-hand and under a powerful digital microscope. At either scale, he looks for specific traits that when taken together help identify the species behind the pieces.
Here in South Africa, there are four main hominid species that have been discovered. The following sketches attempt to illustrate the tell-tale skull characteristics of each, as described to me by Darryl over lunch on his last day in camp.”
(Source: National Geographic)
What about human mate attachment? Are we, by nature, like prairie voles? The answer seems to be that humans are flexible in their mating arrangements. Strong attachments are certainly common, but according to anthropologists George Murdock and Suzanne Wilson, 83% of societies allow polygynous patterns of marriage. Depending on conditions, however, even if polygyny is allowed, most men are of modest means and hence are likely to have only one wife. Consequently, de facto monogamy may prevail, though the wealthier men may have more than one wife. In historical times, it has been well documented that a wealthy man may have a special, long-term attachment to one particular female, even while enjoying, and perhaps impregnating, various other women. So even when polygyny is the local practice, individual inclination may result in long-term attachments.
In the other 17% of societies, both modern and ancient (e.g. Greece and Rome), monogamy has been the practice. The explanation for the cultural variation of marriage practices probably rests mainly with variation in ecological and cultural conditions, and in particular, with whether there are conventions for heritability of property and other forms of wealth, along with wealth to be inherited.
Drawing on historical and ethnographic data, evolutionary biologists Laura Fortunato and Marco Archetti argue that when there are multiple wives each with children and hence multiple heirs, transferring resources to all heirs results in a depletion of their fitness value; for example, the patches of land to bequeath get smaller and smaller, and less able to support the families that depend on the land. A man might select one particular wife whose children inherit all the wealth but this makes for competition among offspring, and is generally an unstable solution. In these conditions, a more stable strategy for enhancing the well-being of one’s own offspring would be to have one wife, be sure of the paternity of the offspring, and invest heavily in the welfare only of her children. Fortunato and Archetti note that monogamy emerged in Eurasia as agriculture became widespread with land and herds as an important source of wealth that could be passed to heirs. Once certain practices become the norm, once they are seen to bring benefits and to circumvent troubles, once they are reinforced by social approval and disapproval, they do of course seem to reflect the only right way for things to be.
Churchland, Patricia Smith. Braintrust: What Neuroscience Tells Us About Morality, p. 58-59. Princeton, N.J.: Princeton University Press, 2011. Print.
No Known Hominin Is Common Ancestor of Neanderthals and Modern Humans, Study Suggests
Oct. 21, 2013 — The search for a common ancestor linking modern humans with the Neanderthals who lived in Europe thousands of years ago has been a compelling subject for research. But a new study suggests the quest isn’t nearly complete.
The researchers, using quantitative methods focused on the shape of dental fossils, find that none of the usual suspects fits the expected profile of an ancestor of Neanderthals and modern humans. They also present evidence that the lines that led to Neanderthals and modern humans diverged nearly 1 million years ago, much earlier than studies based on molecular evidence have suggested.
Reconstruction of Homo erectus from Dmanisi by J.H. Matternes
Source: Skull of early human ancestor unearthed in Georgia – in pictures
See also: A Complete Skull from Dmanisi, Georgia, and the Evolutionary Biology of Early Homo. David Lordkipanidze, Marcia S. Ponce de León, Ann Margvelashvili, Yoel Rak, G. Philip Rightmire, Abesalom Vekua, Christoph P. E. Zollikofer. Science 18 October 2013: Vol. 342 no. 6156 pp. 326-331 DOI: 10.1126/science.1238484
Skull Fossil Suggests Simpler Human Lineage
After eight years spent studying a 1.8 million-year-old skull uncovered in the republic of Georgia, scientists have made a discovery that may rewrite the evolutionary history of our human genus Homo.
It would be a simpler story with fewer ancestral species. Early, diverse fossils — those currently recognized as coming from distinct species like Homo habilis, Homo erectus and others — may actually represent variation among members of a single, evolving lineage. In other words: just as people look different from one another today, so did early hominids look different from one another, and the dissimilarity of the bones they left behind may have fooled scientists into thinking they came from different species.
Archaeologists Rediscover the Lost Home of the Last Neanderthals
Oct. 17, 2013 — A record of Neanderthal archaeology, thought to be long lost, has been re-discovered by NERC-funded scientists working in the Channel island of Jersey.
The study, published today in theJournal of Quaternary Science, reveals that a key archaeological site has preserved geological deposits which were thought to have been lost through excavation 100 years ago.
The discovery was made when the team undertook fieldwork to stabilise and investigate a portion of the La Cotte de St Brelade cave, on Jersey’s south eastern coastline.
Some Monkeys Have Conversations That Resemble Ours
The sounds of marmoset monkeys chattering may hint at the mysterious origins of human language.
A new study shows that marmosets exchange calls in a precisely-timed, back-and-forth fashion typical of human conversation, but not found in other primates. The monkeys don’t appear to have a language, but the timing suggests the foundations of our own.
“That could be the foundation of more sophisticated things, like syntax,” said psychologist Asif Ghazanfar of Princeton University, co-author of the study, which was published today in Current Biology. “You can’t have any of those other really cool aspects of language without first having this.”
Anthropologists Confirm Link Between Cranial Anatomy and Two-Legged Walking
Sep. 26, 2013 — Anthropology researchers from The University of Texas at Austin have confirmed a direct link between upright two-legged (bipedal) walking and the position of the foramen magnum, a hole in the base of the skull that transmits the spinal cord.
The study, published in a forthcoming issue of the Journal of Human Evolution, confirms a controversial finding made by anatomist Raymond Dart, who discovered the first known two-legged walking (bipedal) human ancestor,Australopithecus africanus. Since Dart’s discovery in 1925, physical anthropologists have continued to debate whether this feature of the cranial base can serve as a direct link to bipedal fossil species.