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Human evolution is conspiculously absent from Origin - knowing of the opposition such a suggestion would face, Darwin confined his initial speculation to animals.

Human evolution is conspiculously absent from Origin - knowing of the opposition such a suggestion would face, Darwin confined his initial speculation to animals.

==Criticisms of ''The Origin of Species''==

==Summary==

 

 

In this chapter, Darwin motivates the case for variation and selection by illustrating the variety among the natural and domesticated plant and animal worlds.  Without knowing the details of [[inheritence]] (which would be demonstrated later by [[Gregor Mendel]] and [[Watson]] and [[Crick]] among others) he shows its implications: like breeds like.  Inheritence is what breeders use to direct the variation of species to some useful means.  This is done by selection; the breeders' are keenly aware of the minor differences in the offspring populations of animals and exploit them to create new varieties.  The variation of species is not simply due to crossings of existing varieties.  He argues this by showing examples where it is unlikely or impossible, pigeons, dogs, and talks about recent domestication.  Pigeon varieties completely different in appearence from the the wild rock pigeon show traits of the wild rock pigeon when crossed.  He shows, through the works of breeders, that in fact even animals within the same breed show variation of which expert breeders are aware (conciously or subconciously) and exploit to direct the traits of the offspring.  This he shows convincely, as breeders cannot control traits directly, but can exploit variation to make new breeds because they know the traits are inherited.  During Darwin's time, species was not a well-defined category: animals may be regarded as species or varieties even among prominent naturalists of the time.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

===CHAPTER 14. RECAPITULATION AND CONCLUSION===

 

==External Links==

==External Links==