Bruce Jackson has us thinking about how DNA can help human beings trace their roots, but what about animals? Don’t they have DNA that chronicles their past as well? Carl Zimmer looks to Joshua Drew’s shoulder for answers.
There is no one kind of DNA. Every individual human, earthworm, liverwort, and bacterium carries a version of the molecule with a unique sequence. As living things reproduce and pass down their genes to their descendants, their DNA chronicles their genealogy. Joshua Drew, a conservation biologist at the University of Chicago, dives into the waters around the islands of Indonesia, trawling for DNA. The DNA happens to be in fishes, such as the checkerboard wrasse he had drawn on his shoulder, along with a segment of its DNA. The fishes can swim wherever they are so inclined; their larvae can drift for hundreds of miles in the currents. Yet their DNA, Drew Finds, reveals that they don’t travel far. It sheds light on one of the reasons for the ocean’s biodiversity: homebodiness.
Check out more tattoos in “Science Ink: Tattoos of the Science Obsessed” by Carl Zimmer.