Octopuses have some of the oldest known sex chromosomes

Earth & Climate News -- ScienceDaily · last updated February 4, 2025 – 2:48 PM

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. The finding also is evidence that octopuses and other cephalopods, a class of sea animals that includes squid and nautiluses, do use chromosomes to determine their sex, answering a longstanding mystery among biologists.

here today, more tomorrow

We’ve launched briefing.center with a focus on the press and media.

And we’ve added Citizen Cartwright, a daily quick-read news summary by veteran Washington journalist Linda Cartwright. We’ve also created a new voting rights knowledge center for Citizen Cartwright subscribers. (You can sign up for a dedicated morning email at citizencartwright.com.)

You can sign up here for full access to press and media and Citizen Cartwright on briefing.center.

You can use briefing.center as the center of your information management, or just one of your tools. We’re happy to discuss your information needs.