Human evolution

At MSNBC (6/16/2011), Jennifer Walsh advises us, “Humans are evolving slower than thought” and that “We probably separated from chimps evolutionarily longer ago than expected.”: The researchers found that on average, humans seem to have about 60 new mutations passed down every generation — that’s 60 changes out of 6 billion letters, or bases, that make up the genome. Previous methods, which indirectly calculated the rates, overestimated that number to be about 100 to 200, the researchers said. This means that we are accumulating new genetic mutations — the foundation of evolution — about a third as quickly as previously thought. If this mutation rate has been steady throughout human evolution, it pushes the fork between humans and chimps back Read More ›

After this recent claim that autism was somehow adaptive in the prehistoric era,  many are reading with interest this: Two other studies published in the June 9 issue of Neuron report on the same families studied by State, Sanders and their co-authors. One of these, by a group at Cold Spring Harbor Laboratory in New York, paints a very similar picture — that autism is a highly genetically diverse disorder and that sporadic changes in the structure of the genome present only in the affected individuals and not in other families often play a key role.The other study, by researchers at Columbia University, suggests that although hundreds of genes may be involved in autism, they appear to disrupt a common Read More ›

“A new find has muddied the waters on the origins of Homo erectus,” Nature confides. Hammered them to bits, actually.

Reid Ferring, an anthropologist at the University of North Texas in Denton, and his colleagues excavated the Dmanisi site in the Caucasus Mountains of Georgia. They found stone artefacts — mostly flakes that were dropped as hominins knapped rocks to create tools for butchering animals — lying in sediments almost 1.85 million years old. Until now, anthropologists have thought that H. erectus evolved between 1.78 million and 1.65 million years ago — after the Dmanisi tools would have been made. – Matt Kaplan, Human ancestors in Eurasia earlier than thought”, (6 June 2011) Read More ›

How common is common descent?A question worth asking, in light of a new paper: Casey Luskin advises (Evolution News & Views, June 3, 2011) that “Study Reports a Whopping “23% of Our Genome” Contradicts Standard Human-Ape Evolutionary Phylogeny”:

We’ve recently discussed different genetic studies on primate relationships were finding contradictory evolutionary trees. As discussed, one recent study found data that conflicted with the standard primate phylogenetic tree, reporting that “for ~0.8% of our genome, humans are more closely related to orangutans than to chimpanzees.” We then commented: 

0.8% of our genome might not sound like a lot, but that equates to over 20 million base pairs. That’s means that over 500 times more raw genetic information than was used in the PLoS Genetics paper (to purportedly create a “robust new phylogenetic tree”) is supposedly pointing in the wrong phylogenetic direction. Read More ›

In “Going ape: Ultraviolence and our primate cousins,” New Scientist’s News Editor, Rowan Hooper, reviewing a book on ape violence, riffs,

Josephine Head, also of the Max Planck Institute, describes how she tracked a trail of blood from where chimps had been vocalising loudly the night before, and made a horrible discovery: the spread-eagled body of an adult male chimp, his face battered and bruised, throat torn open and intestines dragged out. Read More ›

In “Autism May Have Had Advantages in Humans’ Hunter-Gatherer Past, Researcher Believes”
(ScienceDaily, June 3, 2011), we are told

The autism spectrum may represent not disease, but an ancient way of life for a minority of ancestral humans, said Jared Reser, a brain science researcher and doctoral candidate in the USC Psychology Department. Some of the genes that contribute to autism may have been selected and maintained because they created beneficial behaviors in a solitary environment, amounting to an autism advantage, Reser said.

Parents of autistic children will wonder about that. One such knowledgeable source commented, “But a feature of autistic/Asperger’s people is that their focused attention is generally toward things that do not provide important survival skills and that they are not as aware of their surroundings ”

Language warning: Present tense of observable fact is used in the main text sentence above and in those below. Read More ›

In “Ancient Hominid Males Stayed Home While Females Roamed, Study Finds (ScienceDaily, 2011), we learn,

The team, which studied teeth from a group of extinct Australopithecus africanus and Paranthropus robustus individuals from two adjacent cave systems in South Africa, found more than half of the female teeth were from outside the local area, said CU-Boulder adjunct professor and lead study author Sandi Copeland. In contrast, only about 10 percent of the male hominid teeth were from elsewhere, suggesting they likely grew up and died in the same area.

If these results are replicated, early human culture encouraged the idea that women should go live with their husbands instead of staying with their folks. Let’s give that one time to sink in. It’s novel …  Read More ›

Here’s an intellectually respectable “Blast from the past” to understand the motives, a (August 23, 2008), “The Soviet ape-man scandal” by New Scientist’s Stephanie Pain:

When Ivanov put his proposal to the Academy of Sciences he painted it as the experiment that would prove men had evolved from apes. “If he crossed an ape and a human and produced viable offspring then that would mean Darwin was right about how closely related we are,” says Etkind. Read More ›

This from Martin Eiermann’s (The European, 30.05.2011) interview with Stewart Brand, author, biologist, and environmental activist from the 1960s onward:

Brand: Steven Pinker [materialist cognitive scientist (Harvard)] is currently working on a book about the decline of violence through human history. We like to think that we are living in a very violent time, that the future looks dark. But the data says that violence has declined every millennium, every century, every decade. The reduction in cruelty is just astounding. So we should not focus too much on the violence that has marked the twentieth century. The interesting question is how we can continue that trend of decreasing violence into the future. What options are open to us to make the world more peaceful? Those are data-based questions.  Read More ›

Which shows how number sense evolved? Forget them. In “Geometry skills are innate, Amazon tribe study suggests,” (BBC News , 24 May 2011), Jason Palmer reports ,

Tests given to an Amazonian tribe called the Mundurucu suggest that our intuitions about geometry are innate.Researchers examined how the Mundurucu think about lines, points and angles, comparing the results with equivalent tests on French and US schoolchildren.

The Mundurucu showed comparable understanding, and even outperformed the students on tasks that asked about forms on spherical surfaces.

It got better: Read More ›

At Outside Online (“Fair Chase,”May 2011), Charles Bethea tells us

On the plains of New Mexico, a band of elite marathoners tests a controversial theory of evolution: that humans can outrun the fastest animals on earth.

Controversial? Yes, apparently:

As ridiculous as this spectacle might appear, the men are testing a much-debated scientific notion about when and how humans became hunters. Between two and three million years ago, when our australopithecine ancestors ventured out of the forests and onto the protein-rich African savanna, they were prey more often than hunter. They gathered plant-based foods, just as their primate brethren did. Then something changed. They began running after game with long, steady strides. Evolutionary biologists like Harvard’s Dan Lieberman think the uniquely human capacity for endurance running is a distant remnant of prehistoric persistence hunting.

You’ll have to read the article to see if the runners succeeded and whether they think they proved something (another story). Read More ›

Genome mapper Francis Collins, who founded BioLogos, is hailed in the June 2011 article as “one of the most eminent scientists ever to identify as an evangelical Christian.”

An unexpected paean – and one that furrowed my brow (p. 23).   Read More ›

Dennis Venema, Biologos’s senior fellow for science, and biology chair at Canada’s evangelical Trinity Western University, would have us know (p. 25) that the chimp genome(total genetic heredity encoded in DNA), which was fully mapped by 2005,displays “near identity”with the human genome as detailed by Collins’s team, with a 95 to 99 percent match depending on what factors are included. As Reasons to Believe biochemist Fuz Rana has pointed out (and he’s quoted), that would merely suggest that genes don’t count for much in determining what an entity will be like. As a result, the figure is widely disputed. Here’s geneticist Richard Buggs to start. More notes on Christianity Today’s “Darwin ‘n Jesus ‘n me” article here. The article here.

Or so some paint it. I’ve now had a chance to read Christianity Today’s “The Search for the Historical Adam” by Richard N. Ostling (June 2011). Recommended to all. I’m not sure re crisis. I think it comes down to a simple choice. Linked here. Some notes follow: Read More ›

Here’s the intro to the contest, riffing off the bewildering soap opera of claims about the relationship between modern humans and Neanderthals, followed by the question, for a free copy of The Nature of Nature , tell us: Do you think we understand the human-Neanderthal relationship better than we did twenty-five years ago? In what ways?

The responses here went down a range of paths, only some being on topic, perhaps due to the specificity of the question.

Two book prizes are awarded, Read More ›