Sponge (animal)

Porifera Temporal range: Ediacaran–recent PreꞒ Ꞓ O S D C P T J K Pg N
A stove-pipe sponge
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Porifera Grant, 1836
Type species
Amphimedon queenslandica[1]
Classes
Calcarea Hexactinellida Demospongiae Homoscleromorpha †Stromatoporoidea
Synonyms
Parazoa/Ahistozoa (sans Placozoa)[2]

A sponge is a member of the phylum Porifera. It is a simple animal with many cells, but no mouth, muscles, heart or brain. It is sessile: it cannot move from place to place the way most animals can. A sponge is an animal that grows in one spot like most plants do. Nevertheless, sponges are quite successful.

The basic body plan is a jelly-like layer sandwiched between two thin layers of cells. Their bodies are full of pores and channels allowing water to circulate through them. Most of them feed on bacteria and other microorganisms. A few of them eat tiny crustaceans.

There are more than 10,000 species of sponge. Most sponges live in the ocean. A few live in fresh water. All sponges take in water through pores (little holes) in their bodies. The water goes out through a big tube in the center. Most sponges filter (take out) little bits of food from the water going through their bodies. Animals that get food this way are called filter feeders.

Sponges are the oldest animals with fossil evidence (from ~635 million years ago).^[3]

1. ↑ Srivastava M, Simakov O, Chapman J, Fahey B, Gauthier ME, Mitros T, et al. (August 2010). "The Amphimedon queenslandica genome and the evolution of animal complexity". Nature. 466 (7307): 720–6. Bibcode:2010Natur.466..720S. doi:10.1038/nature09201. PMC 3130542. PMID 20686567.
2. ↑ Pajdzińska A (2018). "Animals die more shallowly: they aren't deceased, they're dead. Animals in the polish linguistic worldview and in contemporary life sciences" (PDF). Ethnolinguistic. 29: 147–161. doi:10.17951/et.2017.29.135.
3. ↑ Animals, Mindy Weisberger 2018-10-25T12:14:32Z (25 October 2018). "Traces of Earth's oldest animals possibly found". livescience.com. Retrieved 2019-09-30.{{cite web}}: CS1 maint: numeric names: authors list (link)