Here's a new development in the search I described last week for the genes that make us uniquely human. Science's Michael Balter reports on a new study about a gene that's crucial for making big brains. Mutant versions of the gene produce people with tiny brains--about the size that Lucy had 3.5 million years ago. Comparisons of the human version of the gene with other mammals shows that it has undergone intense natural selection in our own lineage.
Size is far from everything, however. While humans have huge brains compared to other mammals, new kinds of wiring may have been more important in the transformation of the hominid brain into something that could be called truly human.
More like this
This week a few more tantalizing clues about the origin of language popped up.
I blogged here and here about a fierce debate over the evolution of language. No other species communicates quite the way humans do, with a system of sounds, words, and grammar that allows us to convey an infinite number…
Our ancestors branched off from those of chimpanzees some six million years ago. Since then, our lineage became human--and distinctly unlike other apes. Figuring out how that difference evolved is one of the grand challenges of biology. Until now, scientists have gotten most of their clues by…
Judging from fossils and studies on DNA, the common ancestor of humans, chimpanzees, and bonobos lived roughly six million years ago. Hominids inherited the genome of that ancestor, and over time it evolved into the human genome. A major force driving that change was natural selection: a mutant…
Science is so specialized these days that it's hard for scientists to look up beyond the very narrow confines of their own work. Biologists who study cartilage don't have much to say to biologists who study retinas. Astronomers who study globular clusters probably can't tell you what's new with…
ASPM really is a pretty cool gene -- I just listed a few other intriguing facts about it on Pharyngula.