Here's something you don't see every day: the birth of thousands of octopi, caught on film.
These tiny octopuses are the offspring of a Caribbean Octopus vulgaris acquired by the Steinhart Aquarium at the California Academy of Sciences in San Francisco in January. Soon after the octopus moved into the aquarium, biologist Richard Ross writes on his blog at Advanced Aquarist, she surprised everyone by laying eggs. Three weeks later, those eggs hatched, turning the octopus' tank into a "snow globe" of baby octopi, or paralarvae. [See a close-up and video of the baby octopi]
Each hatchling is 0.04 inches (1 to 2 millimeters) long. After they were born, the aquarium fed the baby octopi even tinier brine shrimp and zooplankton. Unfortunately, Ross wrote, octopus paralarvae are difficult to keep alive in captivity, though many survived up to 26 days.
The tale has a sad end for mom, too. This species of octopus stops eating after she lays her thousands of eggs and then dies soon after they hatch. The mother O. vulgaris lived about two weeks after her larvae emerged, Ross told LiveScience.