octopus vulgaris

5

More anomalous Japanese octopuses. This condition doesn’t afflict only one arm per individual; one specimen captured in 1884 (first image) had a total of 90 branches, with all arms being affected but one. Another individual captured in 1957 (third image) had 72 branches, with all of its arms being affected; one of the arms (L1) was split so deeply it gave the impression of two separate arms. The cause of this condition is unknown, although since the nerves split far before the arms do externally it is apparently not due to regeneration.

Okada, Y.  On Japanese Octopuses with branched Arms, with Special Reference to their Captures from 1884 to 1964. Proceedings of the Japan Academy 41(7) 618–623.

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These gif shows the first record of cannibalistic behavior of the common octopus (Octopus vulgaris) in the wild, recorded with a camcorder by scuba divers in Ría de Vigo, Spain, on the northeastern Atlantic coast.

These records document common traits in cannibalistic behavior: (a) it was intercohort cannibalism; (b) attacks were made by both males and females; © in one case, the prey were transported to the den, which was covered with stones of different sizes; (d) the predator started to eat the tip of the arms of its prey; (e) predation on conspecifics occurred even if there were other abundant prey available (i.e., mussels)

Cannibalistic behavior in octopuses may be motivated by various factors,  they may resort to cannibalism as a means of defending their territory.

Although scientists had been aware of cannibalism occurrences among members of O. vulgaris, the previously reported cases were known only from analysis of stomach contents and laboratory observations.

Octopus Inside A Bottle by julesnene on Flickr.

Via Flickr:
Looking inside the aquarium, i moved closer to make sure it was a live octopus inside a bottle. I wondered how he was able to get inside a bottle then realized something moved. His slit-shaped pupil blinked and then finally I realized it was the octopus eye! :)