Aplysia californica

Aplysia californica (also California sea hare or California sea slug) is a species of sea hare which belongs to the class Gastropoda in the phylum Mollusca.

It is a very large sea hare, growing to a recorded length of 75 cm. But most are smaller.

The California sea hare is herbivorous. Its diet consists primarily of red and brown seaweed, which gives the animal its typically dark coloration.

Table of contents

1 Life cycle 2 Laboratory use 3 Photos 4 References

Life cycle

Like all sea hares, the California sea hare is hermaphroditic, acting as male and female simultaneously, even during mating. The eggs are yellow, but after 8 to 9 days change into a brown color before hatching into larvae. When this annual animal is laying eggs, it has reached the end of its life. Its lifetime depends somewhat on the temperature of the water: 14-25 degrees Celsius is best, but a somewhat cooler temperature delays spawning and extends its life somewhat.

Laboratory use

Aplysia californica has become a valuable laboratory animal, used in studies of the neurobiology of learning and memory. Its ubiquity in synaptic plasticity studies can be attributed to its simple nervous system, consisting of just a few thousand large, easily-identified neurons. Despite its seemingly simple nervous system, however, Aplysia californica is capable of a variety of non-associative and associative learning tasks, including sensitization, habituation, classical, and operant conditioning. Study typically involves a reduced preparation of the gill and siphon withdrawal reflex.

Photos

• Aplysia californica, from the Sea Slug Forum
• Learning in Aplysia californica, from brembs.net

• NIH/University of Miami National Resource for Aplysia Facility