Thursday, August 25, 2011

Keeping up with the Hominin

In less than a week, some of you will be shuffling back to school as Fall session begins. Every new semester, without a doubt, you'll be able to pick out the smart ass in the class. You know, the ones that sit in front of the class and always have their hands up when the professor asks a question (think Hermione Granger). But what if you are the smart ass? Have no fear, you're reading the right post.

"Hominin - the group consisting of modern humans, extinct human species and all our immediate ancestors (including members of the genera Homo, Australopithecus, Paranthropus and Ardipithecus)."

A lot had happened this year with hominin research and some would redefine conventional understandings of this group. Below is a list of new studies that came out this year that I find quite interesting on hominin. Read up so you can show off in class with your knowledge of current hominin research. You know, just so you can make sure that your adjunct is really paying attention of what he/she is doing instead of begrudgingly teaching a class because he/she has to. Or maybe you have a geeky classmate you want to impress. Or if you're like me, you just wanna be the smartest in class because Asian Fail is not an option. So, enjoy ... and if they question you, tell them I said so.

Australopithecus africanus and Paranthropus robustus

Paranthropus boisei

From left to right: Comparison of upper jaw, P. boisei and H. sapiens. Photo from PhysOrg.

Homo erectus

  • Stone artifacts, mostly flakes from stone tools, from the Dmanisi site in Georgia (the country, not the state) might suggests that H. erectus evolved outside of Africa. However, no conclusive evidence can be made due to the poor conditions of fossils found near these artifacts. Human ancestors in Eurasia earlier than thought
  • H. erectus reached South Asia earlier than previously thought, between 1.5 to 1 million years ago according to Acheulean tools. Go east, ancient tool makers
An Acheulean hand ax found in India (South Asia) indicates that H. erectus moved to South Asia shortly after the invention of stone tools, around 1.6 million years ago. Photo from ScienceNews.

Homo neanderthalensis

  • Neandertals probably died off because there were too many early humans to compete with. According to a statistical analysis, the PĂ©rigord region of southwestern France has the highest concentration of Neandertals and early humans. The ratio between Neandertal to early human was 1 to 10. There were just too many humans for Neanderthals to survive
  • Mousterian culture might have lasted longer than previously thought and Neandertals might have spread as far as northern Russia in the mountains of Polar Urals, near the Arctic Circle. Last Neanderthals Near the Arctic Circle?

Homo floresiensis (the Hobbits)

  • The debate whether H. floresiensis is a separate species or just microcephalic H. sapiens continues on. New study shows that the measurement of the Hobbit skull is within the range of microcephalic H. sapiensTaking the measure of a hobbit
From left to right: Homo floresiensis (LB1) and Homo sapiens.

Homo sapiens (early and modern humans)

*Bouchra child, Homo sapiens*

  • Dr. Harold Dribble and his team found the skull of "world's oldest human child" dated around 108,000 years old in Morocco and nicknamed it Bouchra. The boy died when he was 8 years old. This specimen has not been described in any scientific paper so watch out for it soon. World’s Oldest Child Found in Morocco

Thursday, August 11, 2011

Someone Cited My Thesis!

Some time last week, a little birdie sent me a link to what appears to be a page from American Museum of Natural History (AMNH). Said birdie also mentioned that the link has to do with my honors thesis. Along with the link was a thumbnail of a male hamadryas baboon that looked rather familiar. It took me a few seconds to realize that I am looking at Fadi, or Moja as what he is referred to by the zoo. (Follow this link for who's who at Prospect Park Zoo) Confused as to what my honors thesis, Moja and AMNH have in common, I opened the link. The link directed me to one of AMNH's Young Naturalist Awards winner, a young gentleman by the name of Henry.

Henry's winning entry is Hamadryas Baboons, Papio hamadryas: Captive vs. Wild. His research was on hamadryas baboon behaviors, where he compares the Prospect Park Zoo troops with the ones from Larissa Swedell's field work in Ethiopia. And guess what, he cited my thesis! I'm excited that someone dug up my baby and used it in their research. This is the first time (that I know of) someone actually cited my research. I'm so glad I uploaded my honor thesis on Scribd instead of just letting the bound copy collect dust in my college's library. Anyway ...

Henry's research is quite interesting. He found that there are behavioral differences between captive and wild hamadryas baboons. Also, grooming was not the highest in frequency compared to other behaviors (sitting was the highest in frequency). This could be explained by the hot weather or the fact that data for this research was only collected for about 9 hours. Nonetheless, this is heading in a good direction and a pretty good research topic for a 15 year-old. Hopefully he'll stick to his passion for primates (baboons) and go on to be the next primatologist.

Note that the male hamadryas photo "Simen, a 19-year-old Alpha Male" (above) is actually Moja, Simen's offspring. Simen can be identified with a mole underneath his left eye, which is absent in this photo. Click on the link to read my thesis, A Cross-Species Comparative Study: Grooming Patterns in Captive Populations of Hamadryas Baboons and Geladas.

Tuesday, August 2, 2011

20 million-year-old well preserved fossil skull: Ugandapithecus major

Map of Uganda showing the remote Karamoja region in the northeast of the country where a team of Ugandan and French paleontologists announced Tuesday they had found a 20-million-year-old ape skull, saying it could shed light on the region's evolutionary history. Illustration from PhysOrg.

A well preserved fossil skull of an ancient primate, Ugandapithecus major, has been excavated in the northeast region of Karamoja in Uganda (hence the genus name, Uganda monkey). The 20 million-year-old skull belongs to a male and probably died when it was about 10 years old, said researchers Pickford and Senut. The cranial size of Ugandapithecus major was about the same size as that of chimpanzees but its brain size is smaller. Ugandapithecus major is a tree-climbing catarrhine, an herbivore that lives around the Miocene. Although its genus name refers to it as a monkey, Ugandapithecus major is actually a hominoid (ape).

A well preserved skull of Ugandapithecus major. Photo from BBC News
The skull will be cleaned and prepared in France for about a year before returning it back to Uganda. Ugandapithecus major was described in 2000 by Senut et al. from a few dental and postcranial remains.

You can read Senut et al. (2000) A new genus of Early Miocene hominoid from East Africa: Ugandapithecus major (Le Gros Clark & Leakey, 1950) here (requires subscription).