Tag Archives: Human Evolution

Fossilized Foot Sheds New Light on Evolution of Bipedalism

Paleoanthropologists have long looked to early hominids to answer questions about our own development and evolution. The most famous example is the Australopithecus Lucy, who roamed the African savannah more than 3 million years ago.

Recently, paleoanthropologists have uncovered a fossilized foot close to Lucy’s age but with details resembling an older species of proto-human, Ardi. The find provides scientists with new details and information on the evolution of bipedalism in humans.  To learn more about the discovery, see the article in Scientific American.

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Mapping of Bonobo Chimpanzee Genetic Code Reveals More About (Us) Humans

Bonobos at the Cincinnati Zoo (courtesy of Wikipedia)

Scientists have recently mapped and published the genetic code of the Bonobo Chimpanzee (Pan paniscus); our closely related primate cousins. Bonobo Chimps, sometimes called pygmy or gracile chimpanzees, share 98.7% of their DNA with human beings (on par with the common chimpanzee, Pan troglodytesThe two species of chimpanzee share more than 99% of their genetic code, but have clearly distinct social constructions and inherent behaviors.

Common chimpanzees are characterized by not only their intelligence, but their often violent (sometimes inexplicably so) behavior. Whereas their primate “siblings,” Bonobos, are inherently peaceful, egalitarian, and matriarchal (the only group of great apes with a female-focal social construct).

Scientists hope that these new genetic revelations will help us to understand concepts of ‘inherently human’ behavior – specifically concepts of empathy, cooperation, and peaceful negotiation (all behaviors human beings can and do express).

“If you look at bonobos, chimpanzees and humans, what you can see is that there are some specific characteristics that we share with both of them.”

Scientists hope to study the genetic distinctions to help understand what is inherent versus learned social behavior that we may have genetically inherited from our distant, primate ancestors. To learn more about this research, see the articles: “‘Hippie Chimp’ DNA may shed light on our Dark Side” at MSNBC and Bonobo’s Genetic Code Laid Bare at the BBC.

Cooking a Nearly Two Million Year Old Practice

Recent excavations and analysis of the molars of Homo erectus and Homo sapiens neanderthalensis suggest that human ancestors began cooking much earlier than originally thought. The introduction of culturally treating food (specifically cooking) directly correlates to smaller molar size in human beings (as thick enamel and wide chewing surfaces are no longer necessary).

Paleoanthropologists have suggested that the the decreasing size of molars in proto-humans suggests that our ancestors were cooking as early as two million years ago. The finding, however, is not without controversy as the connection with cooking also suggest other sophisticated tool use – specifically the control of fire.

“There isn’t a lot of good evidence for fire. That’s kind of controversial,” Organ said. “That’s one of the holes in this cooking hypothesis. If those species right then were cooking you should find evidence for hearths and fire pits.” (MSNBC)

These new findings were published in the Proceedings of the National Academy of Sciences. If you do not have a subscription to this esteemed article, you can read more about it in this article of Scientific American or at MSNBC.

Chimpanzees Can Display Altruism

New recent on the behavior of chimpanzees demonstrates that our closest living relatives do in fact display altruistic behavior. Previously, primatologists believed that chimpanzees solely demonstrated behavior for self-serving ends. However, recent behavioral models have shown that the great apes take into account the feelings and needs of others in the group.

 “All studies with wild chimpanzees have amply documented that they share meat and other food abundantly, that they help one another in highly risky situations, like when facing predators or neighboring communities, and adopt needing orphans.” — Christopher Boesche to Discovery News.

These findings also shed an interesting light on the existence and development of altruistic behaviors amongst humans and the role it played in our evolutionary and social progression. To learn more about these findings and the future of these research models, see this article in Discovery News or at MSNBC.

 

Paleoanthropologists Uncover 20 Million Year Old Hominid Fossil

A team of Ugandan and French Paleoanthropologists have uncovered the remains of a 20 million year old Hominid Fossil in Uganda. The find is especially important as the skull is nearly complete – a rarity in fossilized remains.

“This is the first time that the complete skull of an ape of this age has been found. It is a highly important fossil,” Martin Pickford, a paleontologist from the College de France in Paris, told a news conference.

The skull was identified as belonging to a Ugandapithecus Major, an early relative to the great apes that inhabited the region. The early ape had a skull roughly the size of a chimpanzee, a highly intelligent primate. To read more about the find, read one of the articles at Discovery News, MSNBC, Daily Mail, or BBC News.

 

 

First Humans to Leave Africa Continued to Interbreed with Africans

This month’s Nature includes a recent genetic study of human genetics and inter-breeding. The new study indicates that the original humans to leave Africa remained reproductively active with Africans as recently as 20,000 years ago. These conclusions were largely drawn from data found in mitochondrial DNA (passed on, unchanged from Mother to child), tracking back ancestry hundreds of generations. The data highlights the close relatedness of all human beings, regardless of skin color.

You can read more about this study in Nature (if you have a subscription) or in this wonderful synopsis by Scientific American.

Early Pre-Human Societies: Sex-Based Migration Patterns

A new study published in this month’s edition of Nature shows evidence that early hominins (pre-human groups), specifically Australopithecus africanis and Paranthropus robustus demonstrate evidence that the males were more sedentary – often staying within close proximity to their home cave settlements, wherease the females were peripatetic – often migrating hundreds of miles within their lifetime.

If true, this study demonstrates that hominins (including humans) correlate to standing behaviors we see in other groups, such as Chimpanzees, but conflicts with the behaviors we see in Gorillas or Baboons

Such a pattern is similar to that seen in chimpanzee societies, where males in a particular locale tend to stick together to defend their turf from interlopers. In order to guard against inbreeding, the younger females are likelier than the males to migrate for mating. Copeland said the situation is different for gorillas. In those societies, the dominant male gorilla rules over a harem that tends to stay put, while younger males usually have to go someplace else to find their own mates.

This study can help us to understand the mating and migratory roles of early hominin groups. You can read more about this discover in this month’s Nature or via the Cosmic Log at MNSBC.