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neotenyenUK
ne·ot·e·ny N0060050 (nē-ŏt′n-ē)n.1. The retention of juvenile characteristics in the adults of a species, as among certain amphibians. Also called pedomorphism, pedomorphosis.2. The attainment of sexual maturity and subsequent reproduction by an organism still in its larval stage. Also called pedogenesis2. [New Latin neotenia : neo- + Greek teinein, ten-, to extend; see tenesmus.] ne′o·ten′ic (nē′ə-tĕn′ĭk, -tē′nĭk), ne·ot′e·nous (-ŏt′n-əs) adj.neoteny (nɪˈɒtənɪ) or neoteinian (Zoology) the persistence of larval or fetal features in the adult form of an animal. For example, the adult axolotl, a salamander, retains larval external gills. See also paedogenesis[C19: from New Latin neotenia, from Greek neo- + teinein to stretch] neotenic, neˈotenous adjne•ot•e•ny (niˈɒt n i) n. 1. the production of offspring by an organism in its larval or juvenile form; the elimination of the adult phase of the life cycle. 2. the retention in adulthood of a feature or features that appeared in an earlier phase in the life cycle of ancestral individuals. [1900–05; < New Latin neotēnia < Greek neo- neo- + teín(ein) to stretch + -ia -y3] ne•ot′e•nous, adj. neotenythe capacity or state of becoming sexually mature in the larval stage. — neotenous, adj.See also: InsectsThesaurusNoun | 1. | neoteny - an evolutionary trend to be born earlier so that development is cut off at an earlier stage and juvenile characteristics are retained in adults of the speciesevolutionary trend - a general direction of evolutionary change |
neotenyenUK
neoteny (nēŏt`ənē), in biology, sexual maturity reached in the larval stage of some animals. Certain environmental conditions can inhibit the completion of metamorphosis; low temperature or lack of available iodine retard the action of the thyroid gland, the larval form may mature sexually, mate, and produce fertile eggs. If environmental conditions improve, neoteny is reversible; i.e., the larvae can complete metamorphosis and attain normal maturity. When neoteny occurs in some salamanders (see axolotlaxolotl , a salamander, Ambystoma mexicanum, found in certain lakes in the region of Mexico City, which reaches reproductive maturity without losing its larval characteristics. ..... Click the link for more information. ), they remain aquatic. In insects, reproduction in the larval stages is known as paedogenesis; it occurs in certain beetles and gall midges. In the midges, the daughter larvae produced within a mother larva consume the mother and escape; the process may continue for several generations.Neoteny the ability of certain organisms to attain sexual maturity and reproduce during the larval stage or elsewhere in their early ontogeny. Neoteny is known to occur in some amphibians, arthropods, and worms, and in many plants. The larvae of the caudate salamanders of the genus Ambystoma, or axolotls, are the classic example of neoteny. Axolotls lost the capacity for metamorphosis but are able to reproduce, retaining the form of an aquatic animal with gills, fins, and other larval organs. Neoteny gave rise to the perennibranch caudate amphibians, such as the cave proteus (Necturus maculosus), the blind newt (Typhlomolge rathbun), and sirenians. These are matured “larvae” that maintain an aquatic mode of life. In the plant world, neoteny is found among bryophytes, club mosses, ferns, gymnosperms, and angiosperms. For example, the simple organization of structures in the duckweed originated as a result of a cessation in development during one of the earliest stages of ontogeny. An interesting example of neoteny is the female gametophyte in angiosperms, the embryo sac. A. V. IVANOV neoteny[′nē·ə‚tē·nē or nē′ät·ən·ē] (vertebrate zoology) A phenomenon peculiar to some salamanders, in which large larvae become sexually mature while still retaining gills and other larval features. neotenyenUK
neoteny [ne-ot´ĕ-ne] prolongation of the larval form in a sexually mature organism. adj., adj neoten´ic.ne·ot·e·ny (nē-ot'ĕ-nē), Prolongation of the larval state, as in the Mexican tiger salamander or axolotl, or in certain termite castes held in the larval stage as future replacements of the queen. Compare: pedogenesis. [neo- + G. teinō, to stretch] neoteny (nē-ŏt′n-ē)n.1. The retention of juvenile characteristics in the adults of a species, as among certain amphibians. Also called pedomorphism, pedomorphosis.2. The attainment of sexual maturity and subsequent reproduction by an organism still in its larval stage. Also called pedogenesis2. ne′o·ten′ic (nē′ə-tĕn′ĭk, -tē′nĭk), ne·ot′e·nous (-ŏt′n-əs) adj.neoteny see PAEDOGENESIS.neotenyenUK Related to neoteny: pedomorphism, paedomorphismWords related to neotenynoun an evolutionary trend to be born earlier so that development is cut off at an earlier stage and juvenile characteristics are retained in adults of the speciesRelated Words |