A domain structure shared by a mammalian defense protein and a bacterial toxic protein suggests that the immune proteins disrupt membranes by forming pores.

The regulatory regions of simultaneously expressed muscle genes are unexpectedly diverse within a sea squirt species, yet each is evolutionarily conserved among species.

Mapping of a rare isotope of nitrogen shows that symbiotic bacteria on the gills of shipworms fix nitrogen and transfer it to nitrogen-poor tissues of the host.