Are we humans simply remodelled apes? Chimps with a tweak? Is the difference between our genomes so minuscule it justifies the argument that our cognition and behaviour must also differ from chimps by barely a whisker? If “chimps are us” should we grant them human rights? Or is this one of the biggest fallacies in the study of evolution? NOT A CHIMP argues that these similarities have been grossly over-exaggerated - we should keep chimps at arm’s length. Are humans cognitively unique after all?
Thursday, 10 February 2011
Scientists discover gene regulation mechanism unique to primates
In the chapter THE RIDDLE VOF THE 1.6% in my book NOT A CHIMP I detail the important discovery that the regulation of protein production by a gene - called gene expression - was a more important factor in divergence of chimps from humans than changes to the actual DNA sequence of the genes. Here two researchers have documented how widespread and unique among the primates is a form of gene regulation that depends on a combination of small transposable junk elements of DNA in all our genomes - Alu elements - and a form of messenger RNA. It will be interesting if further research demonstrates different patterns of this form of gene expression regulation between primate species, and also interesting if they find out that a failure in this form of regulation could lead to forms of undisciplined cell behaviour like cancer.
Monday, 7 February 2011
Are brains shrinking to make us smarter?
In NOT A CHIMP I argue, quoting John Hawks and others, that there is plenty of evidence - including brain size - to show that, if anything, human evolution has speeded up these last 30,000 years or so, not ceased altogether. This article backs that view up. Domestication is clearly involved and, with it, the retention of juvenile characters - neoteny. Here is the key piece of the article:
"Geary and his colleagues used population density as a measure of social complexity, with the hypothesis that the more humans are living closer together, the greater the exchanges between group, the division of labor and the rich and varied interactions between people. They found that brain size decreased as population density increased......But the downsizing does not mean modern humans are dumber than their ancestors -- rather, they simply developed different, more sophisticated forms of intelligence, said Brian Hare, an assistant professor of anthropology at Duke University.
He noted that the same phenomenon can be observed in domestic animals compared to their wild counterparts.
So while huskies may have smaller brains than wolves, they are smarter and more sophisticated because they can understand human communicative gestures, behaving similarly to human children.
"Even though the chimps have a larger brain (than the bonobo, the closest extant relative to humans), and even though a wolf has a much larger brain than dogs, dogs are far more sophisticated, intelligent and flexible, so intelligence is not very well linked to brain size," Hare explained."
"Geary and his colleagues used population density as a measure of social complexity, with the hypothesis that the more humans are living closer together, the greater the exchanges between group, the division of labor and the rich and varied interactions between people. They found that brain size decreased as population density increased......But the downsizing does not mean modern humans are dumber than their ancestors -- rather, they simply developed different, more sophisticated forms of intelligence, said Brian Hare, an assistant professor of anthropology at Duke University.
He noted that the same phenomenon can be observed in domestic animals compared to their wild counterparts.
So while huskies may have smaller brains than wolves, they are smarter and more sophisticated because they can understand human communicative gestures, behaving similarly to human children.
"Even though the chimps have a larger brain (than the bonobo, the closest extant relative to humans), and even though a wolf has a much larger brain than dogs, dogs are far more sophisticated, intelligent and flexible, so intelligence is not very well linked to brain size," Hare explained."