2499: hippocampus: Seahorses, Monsters, & the Brain Oct 15, 2021

The hippocampus is a ridge of the base of the brain thought to control emotion and the nervous system, but it's also the name for the genus a seahorse and a mythical monster. This is because the Ancient Greek ἱππόκαμπος (hippókampos) literally means "horse sea-monster", which in Greek mythology consisted of a mermaid style horse-headed-fish-bodied and often winged creature. Little seahorses took this as a Latin name, despite the non-Latin origins. As far as its connection to the brain goes, this was not immediately obvious and the first descriptions go from the idea of a silkworm or ram's horns—even proposing another myth-based name 'Ammonis'—but did later reference its shape to the seahorse which eventually won out.