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#编者信息
熊荣川
明湖实验室
xiongrongchuan@126.com
http://blog.sciencenet.cn/u/Bearjazz
A homoplasy is a character shared by a set of species but not present in their common ancestor. A good example is the evolution of the eye which has originated independently in many different species. When this happens it is sometimes called a convergence. Homoplasies can be compared with homologies, which are characters shared by a set of species and are present in their common ancestor.
Note that the above definition of homoplasy is its technical definition used by biologists. A homoplasy has an older, pre-Darwinian meaning of similarity explained by a shared way of life. For example, the wings of insects, birds and bats are all needed for flying: they are homoplasious structures in the non-evolutionary, as well as the evolutionary, sense.
| 异源同形(非同源相似)是一组物种共有的特征,但该特征不存在于它们的共同祖先中。一个很好的例子是眼睛的进化,它独立起源于许多不同的物种。这种情况发生时,有时也被称为趋同。异源同形可以与同源进行比较,同源是一组物种共享的特征,且该特征存在于它们的共同祖先中。 请注意,上述异源同形的定义是生物学家为便于操作给出的技术定义。它还有一个古老的,可追溯到达尔文之前的意义,即因为生活方式相似而产生的相似性。例如,昆虫、鸟类和蝙蝠的翅膀都是飞行所必需的:无论从进化的角度还是非进化的角度来看,它们都是同形结构。
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| Figure: the wings of birds and bats are homoplasies. They are structurally different: the bird wing is supported by digit number 2, the bat wing by digits 2-5.
图:鸟类和蝙蝠的翅膀是异源同形的。它们在结构上是有差别的:鸟翼由第2指支撑,蝙蝠翼由第2-5指支撑。 |
http://www.blackwellpublishing.com/ridley/a-z/homoplasies.asp
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