Howtown

The family tree

Added 2024-07-12 18:19:57 +0000 UTC

I'm sharing a high-resolution file of the family tree from this week's video on invertebrate sentience, along with the sketch that I made and the references I was working from.

My goal was to emphasize that we are much more closely related to frogs, fish, and rays than we are to crustaceans or cephalopods. But there are lots of different ways to map these relationships at different scales. I decided to choose the nine most populous phyla (out of the 35 total) and then expand out the mollusks, arthropods, and chordates. You could definitely flip the positions of a lot of these branches wherever there's a fork in the road, but this is the layout that filled the frame best. The vertebrate bias is hard to escape— we just care so much more about things around our size that live in the places we live, but an estimated 95%+ of animal species are actually invertebrates.

All of the images came from the Biodiversity Heritage Library. This is a collection of libraries "working together to digitize the natural history literature held in their collections and make it freely available for open access." Whoever made this project happen has a very special place in my heart.

-joss

p.s. if you're interested in learning about the fossil that I showed briefly to represent the last common ancestor that we share with octopuses and crabs (a marine worm-like creature, a few millimeters long), check out this paper.