“It’s kind of like evolution has reused some of these pieces that already exist, but combined them in new and novel ways,” Nicholas Bellono, molecular biologist, Harvard University. credit Corey Allard.
The sea robin, Prionotus carolinus, has fascinated scientists for decades. It has the body of a fish, the wings of a bird and the legs of a crab.“ Legs on a fish sound like, um, well, that’s one of the weirdest things I’ve ever seen,” said David Kingsley, Stanford. Kingsley and other researchers show that sea robins use their spindly legs to taste stuff, too. His group was interested in identifying what spurred the creation of three pairs of bendable appendages with leg-like bones, muscles and nervous connections. They found a gene called tbx3a, a variation of tbx3, which helps make limbs in human. Using CRISPER gene editing they showed that it plays a critical role in sea robin.