As mist lingers over a Swedish fjord lined with towering, forested cliffs, a group of scientists collect mud from the bottom of the turquoise-colored waters. They’re after brittle stars—marine animals ...

The paper J. Delroisse et al., “A puzzling homology: A brittle star using a putative cnidarian-type luciferase for bioluminescence,” Open Biology, 7:160300, 2017. Degrees of separation Although the ...