Tadpole

Tadpole

A tadpole or polliwog (also pollywog, polliwig, [ [http://www.onelook.com/?other=web1913&w=Polliwig "Polliwig" in Webster's Unabridged Dictionary] ] , polewig, or polwig [http://machaut.uchicago.edu/cgi-bin/WEBSTER.sh?WORD=polwig "Polwig" in Webster's Unabridged Dictionary] ) is the wholly aquatic larval stage in the life cycle of an amphibian.

General description

During the tadpole stage of the amphibian life cycle, most respire by means of autonomous external or internal gills. They do not usually have arms or legs until the transition to adulthood, and typically have dorsal or fin-like appendages and a tail with which they swim by lateral undulation, similar to most fishes.

As tadpoles mature, they most commonly metamorphosize by gradually growing limbs and then (most commonly in the case of frogs) outwardly absorbing its tail by apoptosis. Lungs develop around the time of leg development and tadpoles late in development will often be found near the surface of the water where they breathe air. During the final stages of external metamorphosis, the tadpole's mouth changes from a small enclosed mouth at the front of the head to a large mouth the same width as the head. The intestines shorten to make way for the new diet.Fact|date=October 2008 Most tadpoles are herbivorous, subsisting on algae and plants. Some species are omnivorous, eating detritus and, whenever available, other tadpoles.Fact|date=October 2008

An exception to the rule distinct differences between the tadpole (juvenile) and adult (frog, toad, salamander etc) stages is the axolotl. Axolotls exhibit a property called neoteny, meaning that they reach sexual maturity without undergoing metamorphosis.

Notes

External links

* [http://allaboutfrogs.org/info/tadpoles/ How to Raise Tadpoles]
* [http://tropicalis.berkeley.edu/home/husbandry/raisetads.html Raising Tadpoles to Adulthood (University of California Berkeley)]


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Look at other dictionaries:

  • Tadpole — Tad pole , n. [OE. tadde toad (AS. t[=a]die, t[=a]dige) + poll; properly, a toad that is or seems all head. See {Toad}, and {Poll}.] 1. (Zo[ o]l.) The young aquatic larva of any amphibian. In this stage it breathes by means of external or… …   The Collaborative International Dictionary of English

  • Tadpole — (englisch für „Kaulquappe“) ist: der Originaltitel eines Films mit dem deutschen Titel „Alle lieben Oscar“ die verbreitetste Bauform des Liegedreirades UGC 10214: „Tadpole Galaxy“ (Kaulquappengalaxie) der Name eines Herstellers von Notebooks mit… …   Deutsch Wikipedia

  • tadpole — ► NOUN ▪ the aquatic larva of an amphibian such as a frog or toad, having gills and a tail and lacking legs until the later stages of its development. ORIGIN from an Old English word meaning «toad» + POLL(Cf. ↑poll) (probably because the tadpole… …   English terms dictionary

  • tadpole — (n.) c.1400, from tadde toad (see TOAD (Cf. toad)) + pol head (see POLL (Cf. poll) (n.)) …   Etymology dictionary

  • tadpole — [tad′pōl΄] n. [ME taddepol < tadde, toad + poll, head, hence, toad that seems all head] 1. the larva of certain amphibians, as frogs and toads, having gills and a tail and living in water: as it matures, the gills usually are lost and legs… …   English World dictionary

  • tadpole — /tad pohl/, n. the aquatic larva or immature form of frogs and toads, esp. after the development of the internal gills and before the appearance of the forelimbs and the resorption of the tail. [1400 50; late ME tad(de)pol, equiv. to tad(de) TOAD …   Universalium

  • tadpole — tad·pole (tăd’pōl′) n. ▸ The aquatic larva of a frog or toad, having gills, a long, laterally compressed tail, and in early stages, no limbs. During metamorphosis of a tadpole into an adult, legs and lungs develop, and the tail gradually… …   Word Histories

  • tadpole — UK [ˈtædˌpəʊl] / US [ˈtædˌpoʊl] noun [countable] Word forms tadpole : singular tadpole plural tadpoles a small animal that lives in water and develops into a frog …   English dictionary

  • tadpole — [15] A tadpole is etymologically a ‘toad head’. The word was coined from Middle English tadde ‘toad’ and pol ‘head’ (ancestor of modern English poll ‘voting’, historically a counting of ‘heads’). Tadpoles, with their moonlike faces appearing to… …   The Hutchinson dictionary of word origins

  • tadpole — A man who is dating a woman considerably older then himself. Look at Betty, she s landed herself a tadpole …   Dictionary of american slang

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