File / 22 · The animal that branched

One head, a family tree of tails, and ten names waiting

Surreal underwater greenhouse corridor containing a translucent branching worm with one head and many delicate ends. — Original Nogical illustration · Interpretive image, not microscopy

Branching worms live inside sea sponges with one head leading into a tree-like network of posterior ends. Genomic and anatomical work found 13 distinct forms, including at least ten likely new species and a new genus. Museum specimens dating to 1914 helped reveal them; how many more remain hidden is unresolved.

Next in the drawer →The daughter cell was already carrying a daughter