sensory ecology of marine animals

Evidence of REM sleep has so far not been seen in octopuses, But they have a kind of sleep twitch of their own. Sleeping octopuses flicker. While they rest, some neuronal firing in their optic lobe causes their chromatophores, or pigment-containing cells, to become active. Here is the link-  https://www.sciencealert.com/watch-the-mesmerising-colour-shifts-of-a-sleeping-octopus

A North Pacific right whale was located in the Bering Sea using sound imaging.  It is the first seen in nearly ten years and the total population is believed to be between 30 and 50 individuals; the rarest whale in U.S. waters. Jessica Crance, a scientist with the Alaska Fisheries Science Center who was working aboard a NOAA vessel used an acoustic sound device to find the whales (pictured).

The compound eyes on the two enlarged tentacles of this fan worm from the great barrier reef evolved independently of all other compound eyes in the animal kingdom.  This conclusion was reached through transcriptomic sequencing at Lund University, Sweden.  Future research may provide clues about the origins of new sensory systems and how the first eyes may have arisen.  Here is the source.

Why are Oceans Getting Louder?   This is a really informative video about noise pollution and its effects.