a rift

todropscience:

DUMBO OCTOPUS HATCHLINGS LOOKS LIKE ADULTS

Cirrate octopods, cephalopods known as the dumbo octopuses are among the largest invertebrates of the deep sea. These organisms have long been known to lay single, large egg capsules on hard substrates on the ocean bottom, including cold-water octocorals. Although juveniles have previously been collected in the midwater, cirrate hatchlings have so far never been observed. However, researchers has been able to locate a dumbo octopus eggs in a submarine mountain at 1,900 m, and have discovered that they look and act like adults from the moment they hatch.

The egg capsule is comprised of an external egg case as well as the chorion and developing embryo. Development in cirrates proceeds for an extended time without parental care

-  Dumbo octopus hatchling, with opened egg case attached to octocoral Chrysogorgia artospira collected at 1,965 m depth on Kelvin Seamount, Atlantic Ocean. 

The baby dumbo octopus behavior shows that cirrate hatchlings possess all morphological features required for movement via fin-swimming, for visually and chemically sensing their environment, and for prey capture. The presence of a large internal yolk sac reduces the risk of failure at first feeding. This is enough evidence that dumbo octopods hatch as competent juveniles.

Cold-water octocorals appear to be critical in cirrate life cycle, and their destruction by bottom trawling or mining will impact populations of mobile animals like the charismatic dumbo octopods

• Photo: Tim Shank
• Reference: Shea et al., 2018.  Dumbo octopod hatchling provides insight into early cirrate life cycle. Current Biology.