You can mark you interesting snippets of text that will be available through a unique link in your browser.


Analogy (biology)

Analogy (biology)

Two structures in biology are said to be analogous if they perform the same or similar function by a similar mechanism but evolved separately. Similar structures may have evolved through different pathways, a process known as convergent evolution, or may be homologous.

The concept of analogy is contrasted with that of homology, which refers to two structures that share a common ancestor and share basic structure. Homologous structures may retain the function they served in the common ancestor or they may evolve to fulfill different functions for example, the wings of birds versus the forelimbs of mammals.

External links

* [http://encarta.msn.com/media_461553540_761554675_1_1/Analogous_and_Homologous_Structures.html Pictures of analogous and homologous structures] at [http://encarta.msn.com/ MSN Encarta]


Wikimedia Foundation. 2010.

  
Share  

Look at other dictionaries:

  • Analogy — is both the cognitive process of transferring information from a particular subject (the analogue or source) to another particular subject (the target), and a linguistic expression corresponding to such a process. In a narrower sense, analogy is… …   Wikipedia

  • Biology — • The science on life and living organisms Catholic Encyclopedia. Kevin Knight. 2006. Biology     Biology     † …   Catholic encyclopedia

  • analogy — /euh nal euh jee/, n., pl. analogies. 1. a similarity between like features of two things, on which a comparison may be based: the analogy between the heart and a pump. 2. similarity or comparability: I see no analogy between your problem and… …   Universalium

  • Biology and sexual orientation — Sexual orientation Orientations Asexual · Bisexual · Heterosexual · Homosexual Gender based alternative concepts Androphilia and gynephilia · Human female sexuality  …   Wikipedia

  • biology — /buy ol euh jee/, n. 1. the science of life or living matter in all its forms and phenomena, esp. with reference to origin, growth, reproduction, structure, and behavior. 2. the living organisms of a region: the biology of Pennsylvania. 3. the… …   Universalium

  • Portal:Biology — Wikipedia portals: Culture Geography Health History Mathematics Natural sciences People Philosophy Religion Society Technology  Science …   Wikipedia

  • Spandrel (biology) — Spandrel is a term used in evolutionary biology describing a phenotypic characteristic that is considered to have developed during evolution as a side effect of a true adaptation, specifically arising from a correlation of growth, rather than… …   Wikipedia

  • Devolution (biology) — In common parlance, devolution , de evolution , or backward evolution is the notion that a species can change into a more primitive form. Biologically, it is a misnomer because evolution does not have a direction or motive. So, its reverse is not …   Wikipedia

  • Homology (biology) — For use of the term homologous in reference to chromosomes, see Homologous chromosomes. The principle of homology: The biological derivation relationship (shown by colors) of the various bones in the forelimbs of four vertebrates is known as… …   Wikipedia

  • Objections to evolution — Part of a series on Evolutionary Biology …   Wikipedia