One of the most important evolutionary transitions in human prehistory was the rise of modern humans (Homo sapiens) from earlier hominids. A newly reported fossil from Tanzania provides an important new data point necessary to understand this transition. Continue reading New Hominid Fossil from Tanzania
Tag Archives: Human Evolution
The Boneyard XIII
Grrrrrrrrrrrrr….
Welcome to the Lucky 13th Edition of The Boneyard … the Web Carnival about Bones and Stuff.
“The Boneyard is a blog carnival covering all things paleo, from dinosaurs to pollen to hominids and everywhere in between. It’s held every two weeks (the 1st and 3rd Saturday of the month), traveling around to a different blog for each installment, connecting some of the best blogging on ancient life.”
The previous edition of The Boneyard is here, at Dragon’s Tales. The next edition of The Boneyard will be Here at Archaeozoology. If you would like to submit an entry to the next edition, you may do so here. As always, thanks to Brian for originating and managing this carnival.
Early, somewhat controversial hominid walked like an Australopith
The ape human split is a bit of a moving target. In the 1970s and early 1980s, there were geneticists who placed it at very recent (close to 4 million years ago) and palaeoanthropologists, using fossils, who placed it at much earlier. During the 1980s, the ape-human split moved back in time because of the importance of sivapithecus, then later in time when Sivapithecus slipped and fell out of the hominid/hominin (human ancestor) family tree. Meanwhile the geneticists were moving towards a more and more recent split. At one point not too long ago, all the evidence converged with the split being around five million years ago. The fossils and the genes agreed, and there were rumors (but nothing published) saying that palaeoanthropologists working in Ethiopia were prepared (soon) to announce that one of the fossils dating to this time had “less then fully developed” bipedalism.But science marches on, and the kinds of questions we are asking of the human fossil record are more detailed than the fossil record usually gives up in a mere few decades of research. So new finds came along and everything changed again. Now, there is a new paper by Richmond and Jungers suggesting that one of the earliest hominid, Orrorin tugenensis, was just as bipedal as any australopith, yet is much farther back in time than, and in many ways, different from our genus (Homo). Continue reading Early, somewhat controversial hominid walked like an Australopith
New early human fossil
I have not read the paper yet, but there is a news report out. This will be in tomorrows nature:
MADRID, Spain – A small piece of jawbone unearthed in a cave in Spain is the oldest known fossil of a human ancestor in Europe and suggests that people lived on the continent much earlier than previously believed, scientists say.ADVERTISEMENTThe researchers said the fossil found last year at Atapuerca in northern Spain, along with stone tools and animal bones, is up to 1.3 million years old. That would be 500,000 years older than remains from a 1997 find that prompted the naming of a new species: Homo antecessor, or Pioneer Man, possibly a common ancestor to Neanderthals and modern humans.The new find appears to be from the same species, researchers said.A team co-led by Eudald Carbonell, director of the Catalan Institute of Human Paleo-Ecology and Social Evolution, reported their find in Thursday’s issue of the scientific journal Nature.The timing of the earliest occupation of Europe by humans that emerged from Africa has been controversial for many years.Some archeologists believe the process was a stop-and-go one in which species of hominins — a group that includes the extinct relatives of modern humans — emerged and died out quickly only to be replaced by others, making for a very slow spread across the continent, Carbonell said in an interview.
The Flores Hobbits Were Members of a Separate Species
… according to a new study published in the Proceedings of the National Academy of Sciences. The study compares skull measurements of Flores material with a wide range of other hominid data and concludes that Flores cannot be clustered with Homo sapiens. This is the first published study that takes into account how size affects shape. By correcting for size, this study makes, the authors claim, a more valid comparison between measurements taken on the Flores material and other comparative data. Continue reading The Flores Hobbits Were Members of a Separate Species
Evidence for an ancient lineage of modern humans
It almost seems like there are two separate research project under way regarding the evolutionary history of Homo sapiens. One focuses on recent humans, tends to use DNA as a major source of information, and from this base projects back into the past. This approach tends to confirm the idea that humans share an African origin with a subsequent spread from Africa, with various degrees of complexity in that series of historical events. The other focuses on early human remains, sometimes including remains that would be placed by some in a separate species or sub species. This sort of approach typically results in a similar conclusion regarding the African origin.But the two populations … modern or recent humans and humans several tens of thousands of years old do not necessarily share a history that has been coherently assembled by researchers. Of course, they shared an actual history, but do the lines linked together to make reconstructed phylogentic trees from these two data sources match up or integrate in any sensible way? Not really.A new paper coming out in the Journal of Human Evolution shares some light on how we might connect these similar but unintegrated reconstructions. Continue reading Evidence for an ancient lineage of modern humans
Why the Hobbits of Flores Were Probably Not Broken People
There is a new paper out suggesting that the Flores hominids, known as Hobbits, were “human endemic cretins.”From the abstract of this paper:
… We hypothesize that these individuals are myxoedematous endemic (ME) cretins, part of an inland population of (mostly unaffected) Homo sapiens. ME cretins are born without a functioning thyroid; their congenital hypothyroidism leads to severe dwarfism and reduced brain size, but less severe mental retardation and motor disability than neurological endemic cretins. We show that the fossils display many signs of congenital hypothyroidism, including enlarged pituitary fossa, and that distinctive primitive features of LB1 such as the double rooted lower premolar and the primitive wrist morphology are consistent with the hypothesis. We find that the null hypothesis (that LB1 is not a cretin) is rejected by the pituitary fossa size of LB1, and by multivariate analyses of cranial measures. We show that critical environmental factors were potentially present on Flores, how remains of cretins but not of unaffected individuals could be preserved in caves, and that extant oral traditions may provide a record of cretinism.
Continue reading Why the Hobbits of Flores Were Probably Not Broken People
The Origin of the Human Smile
A colleague and grad student of mine, Rob, just sent me the following question, slightly edited here:
A student in my intro class asked me a good question the other day to which I had no answer. When did smiling cease to be a threat gesture? I have a couple of ideas. One is that with reduced canines, smiling became a way to say “look, I have small canines, I am not a threat to you.” The other is that smiling is based more on a “fear-grin” than a threat. Under this idea, smiling might have been a way of showing deference to others. If everyone shows deference, it would be egalitarian, until the one guy comes along who never smiles. Maybe that’s why bosses often don’t smile. … let me know when you have some free time to have lunch. Tuesdays andWed’s probably work best for me.
Good question, and good ideas as to a possible answer. I have a couple of other ideas to contribute…. Continue reading The Origin of the Human Smile
Human Evolution News
A new genetic analysis of people from around the world adds further confirmation to the African origin of humans. The study of genetic details from 938 individuals from 51 populations provides evidence of how people are related and different, researchers led by Richard M. Myers of Stanford University report in Friday’s issue of the journal Science.
The Potato and Human Evolution
Fallback foods are the foods that an organism eats when it can’t find the good stuff. It has been suggested that adaptive changes in fallback food strategies can leave a more distinct mark on the morphology of an organism, including in the fossil record, than changes in preferred food strategies. This assertion is based on work done by the Grants and others with Galapagos Island finches, by Richard Wrangham and me with hominids, and by Betsy Burr and me with rodents. Continue reading The Potato and Human Evolution
What did the immediate ancestor of chimps and humans look like?
Comparing living chimpanzees to living humans, in reference to the species that gave rise to these two closely related species, is one way to frame questions about the evolution of each species. Continue reading What did the immediate ancestor of chimps and humans look like?
Evolution: The Mind’s Big Bang
Evolution: The Mind’s Big BangI’ve known Shea for years … since before grad school. Going out drinking with this guy was a little dangerous. Almost as dangerous as going out drinking with me.
What is a disease?
“Disease” is a big word. I’d like to address this question by focusing on the difference, or lack of difference, between a poison, a disease, and a yummy thing to eat. It turns out that they may all be the same. Yet different. Continue reading What is a disease?
Seeking Knowledge in Science (Rue Continued)
I’ve not been commenting on the comments on this post about the Myers – Rue debate, but I have been reading them with great interest. The following, while not addressing most of the comments, arises from them. Continue reading Seeking Knowledge in Science (Rue Continued)
The Myers – Rue Debate And Why They Had to Taser Me
Last night, the Campus Atheists, Skeptics and Humanists club (C.A.S.H.) presented a debate between PZ Myers and Loyal Rue on the question: Can religion and science co-exist? I witnessed this event and would like to tell you what happened.
Continue reading The Myers – Rue Debate And Why They Had to Taser Me