|Sea tulips, Pyura spinifera. |
A symbiotic sponge covers its surface.
Giribet et al 2000
They are sea filter-feeders: they live mainly on plankton. They are called tunicates because the adult form is covered by a leathery tunic. This tunic supports and protects the animal. The adults are sessile, stuck to rocks.
The sea squirt has two openings in its small body. One opening, called the oral siphon, sucks water into the animal; the other opening, called the atrial siphon, squirts water out of the animal. Inside is a little basket-like sieve which traps food: so these sea squirts are filter feeders. The Sea squirt can close the holes in its siphons, like a drawstring can close the opening in a bag.
When in its larval state, it looks like a tadpole and is sometimes called a tadpole larva. Like many sea creatures, a sea squirt larva looks very different from an adult sea squirt. The larva swims for a short time and then attaches itself to something on the sea floor, like a rock, transforming into its adult form. It usually stays in one place for the rest of its life.
Scientists have also found out that some species can heal some damage done to them, over several generations. A similar process might be possible for humans.
|Wikispecies has information on: Urochordata.|
- Delsuc F., Brinkmann H., Chourrout D. & Philippe H. (2006). "Tunicates and not cephalochordates are the closest living relatives of vertebrates". Nature. 439 (7079): 965–968. doi:10.1038/nature04336. PMID 16495997.CS1 maint: multiple names: authors list (link)
- Delsuc F., Tsagkogeorga G., Lartillot N. & Philippe H. (2008). "Additional molecular support for the new chordate phylogeny". Genesis. 46 (11): 592–604. doi:10.1002/dvg.20450. PMID 19003928.CS1 maint: multiple names: authors list (link)
- Singh T. R., Tsagkogeorga G., Delsuc F., Blanquart S., Shenkar N., Loya Y., Douzery E. J. & Huchon D. (2009). "Tunicate mitogenomics and phylogenetics: peculiarities of the Herdmania momus mitochondrial genome and support for the new chordate phylogeny". BMC Genomics. 10 (1): 534. doi:10.1186/1471-2164-10-534. PMC 2785839. PMID 19922605.CS1 maint: multiple names: authors list (link)
- Sea Squirt, heal thyself: scientists make major breakthrough in regenerative medicine
- Solomon E. Berg L. & Martin D. 2002. Biology. Brooks/Cole.