Octopuses have some of the oldest known sex chromosomes
BIOLOGY - University of Oregon researchers have identified a sex chromosome in the California two-spot octopus. This chromosome has likely been around for 480 million years, since before octopuses split apart from the nautilus on the evolutionary tree. That makes it one of the oldest known animal sex chromosomes. Doctoral students Gabby Coffing, Andrew Kern and their team described the findings Feb. 3 in the journal Current Biology.