Science of stripes
At first glance, it’s easy to think African striped mice and chipmunks might be close cousins. Both are members of the rodent family, both sport distinctive black-and-white “racing stripes,” and both are active during the day. So how can it be that they actually exist on opposite ends of the rodent family and are separated by some 70 million years of evolution? The answer, according to a team of Harvard scientists, is that both species use a gene that until now had been associated primarily with cranio-facial development to interrupt the development of pigment cells that form their stripes. The findings are outlined in a Nov. 2 study published in Nature. “This is a case where a similar developmental mechanism — the role of this gene — seems to have evolved independently in these two species,” said senior author Hopi Hoekstra, a professor of organismic and evolutionary biology and of molecular and cellular...