Paper Details  
 
   

Has Bibliography
6 Pages
1460 Words

 
   
   
    Filter Topics  
 
     
   
 

Evolution of Giraffe Neck

The Evolution of the Giraffe Neck Throughout time, one theory has remained constant in terms of why giraffes developed longer necks. The idea, which was presented by Charles Darwin states quite simply that giraffes selected for longer necks in order to reach the food that was higher off the ground during the dry season. No one has ever challenged that idea until 1996. Initially, Gould argued that "the story-the giraffe evolved its long neck in competition to reach scare foliage-is supported by no evidence" (18). That's when two scientists, Robert Simmons and Lou Scheepers made the claim that necks evolved for a very different reason: sexual selection. Within this paper, information will be presented that argues both for and against the theories made by Darwin and Simmons and Scheepers.
Giraffes are placed in the family, Giraffidae, separate from other animals such as the camel, deer, and cow. Typically, giraffes are about 19 feet tall and can weigh as much as 4000 pounds. The evolution of modern giraffes began about 1 million years ago from a similar species known as Giraffa jumae. Those species were known for their massive skeletons and antler-like structures, not found on giraffes of today (Simmons 772). Today, there are nine widely excepted subspecies of the giraffes which are differentiated by the spots on the trunks and their geographic region.
In the article, "Winning By a Neck: Sexual Selection in the Evolution of Giraffes," Simmons and Scheepers state their purpose as to evaluate the theory proposed by Darwin as well as present their own. The theory by Darwin known as the Interspecific Feeding Competition has many assumptions that must hold up for it to be true. One assumption is that tall trees must have been present on the African savannas back when the selection took place and that competition was initially tough for food. If food was scarce, it makes sense that the giraffes would evolve to keep their sp...

Page 1 of 6 Next >

Bibliography:
Works Cited Brownlee, A. Evolution of the Giraffe. Nature. Vol. 200:1963. Pp. 1022. Gould, Stephen J. The Tallest Tale. Natural History. May 1996. Pp. 18-27. Kodrick-Brown, A., and J. H. Brown. Truth in Advertising: The Kinds of Traits Favored by Sexual Selection. The American Naturalist. Vol. 124:1984. Pp. 309-323. Simmons, Robert E. Winning By a Neck: Sexual Selection in the Evolution of Giraffe. The American Naturalist. Vol. 148:1996. Pp. 771-786.


    More on Evolution of Giraffe Neck...

    Loading...
 
Copyright © 1999 - 2015 CollegeTermPapers.com. All Rights Reserved. DMCA