Content deleted Content added
Mindmatrix (talk | contribs) m Reverted edits by 72.71.223.220 (talk) to last version by GalianoP3 |
Howardcorn33 (talk | contribs) |
||
Line 174:
=== Unit of change ===
[[File:Richard dawkins.jpg|thumb|left|150px|[[Richard Dawkins]]]]
A common [[unit of selection]] in evolution is the organism. Natural selection occurs when the reproductive success of an individual is improved or reduced by an inherited characteristic, and reproductive success is measured by the number of an individual's surviving offspring. The organism view has been challenged by a variety of biologists as well as philosophers. Evolutionary biologist [[Richard Dawkins]] proposes that much insight can be gained if we look at evolution from the gene's point of view; that is, that natural selection operates as an evolutionary mechanism on genes as well as organisms.<ref>{{cite journal |last=Wright |first=Sewall |title=Genic and Organismic Selection |journal=Evolution |volume=34 |issue=5 |date=September 1980 |pages=825–843 |jstor=2407990|doi=10.2307/2407990|pmid=28581131 }}</ref> In his 1976 book, ''[[The Selfish Gene]]'', he explains:
{{cquote|Individuals are not stable things, they are fleeting. Chromosomes too are shuffled to oblivion, like hands of cards soon after they are dealt. But the cards themselves survive the shuffling. The cards are the genes. The genes are not destroyed by crossing-over, they merely change partners and march on. Of course they march on. That is their business. They are the replicators and we are their survival machines. When we have served our purpose we are cast aside. But genes are denizens of geological time: genes are forever.<ref>{{harvnb|Dawkins|1976|p=35}}</ref>}}
| |||