#NewsBytesExplainer: Deepest known free-living flatworm discovered in the ocean
An ROV operated by Yasunori Kano (University of Tokyo) retrieved egg capsules nearly 6,200 meters deep in the Kuril-Kamchatka Trench;
Keiichi Kakui and Aoi Tsuyuki at Hokkaido University identified them as flatworm cocoons and reported the deepest known record for free-living flatworms, almost twice as deep as the old record.
The discovery was published in Biology Letters.
Each capsule held 3-7 embryos
Each tiny black capsule held three to seven embryos, all at the same stage of development.
Genetic tests showed these deep-sea flatworms are related to shallow-water species, which is pretty surprising.
Surviving down there
Even though these worms live in extreme depths, their early development looks a lot like their shallow-water cousins.
This suggests that surviving down there is more about handling tough conditions than changing how they grow up—giving scientists fresh clues about how life adapts to the deepest parts of our oceans.