Mystery picture

 It's time for a mystery picture. What do you suppose this is?

The happy life of the larger pacific striped octopus

I love octopuses, and it's always struck me as very sad that such beautiful, intelligent creatures are so short-lived. The males die in the months after mating, which in some species involves detaching their hectocotylus (a modified arm used for spermatophore transfer). The females guard their eggs until they hatch and then die of starvation.



That's why I was so happy to read this article about the larger pacific striped octopus, an unusual species in which the females can brood multiple clutches of eggs over her lifetime. These octopuses are also unusually social and can live in groups of up to 40, such odd behaviour that when they were first described, cephalopod biologists didn't believe it and the paper failed peer review.

There is more information and some great pictures at the link, and a heart-wrenching description here of keeping octopuses.

By the way, it's only a coincidence that my first two posts here have been about the Pacific Ocean!

The Pacific White Line

From Commander Mark Hadfield, I learned today about the Pacific White Line. This is, well, a very large line across the Pacific Ocean: at its largest, two km across and several hundred km long! It forms when cold ocean currents, which carry minerals up from the sea floor, meet a front of warmer water. This produces an excellent environment for diatoms to thrive, attracting up to 50% of the fish in the Pacific Ocean to the line while it lasts. It's amazing that so many fish can be concentrated into such a comparatively small volume.

You can see Commander Hadfield's beautiful picture of the Pacific White Line, taken from the ISS, here.