Effects Of Coevolution

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Coevolution is the process by which two or more closely interacting species evolve in response to one another. Darwin is attributed with first hypothesizing coevolution in “On the Origin of Species” published in 1859; since that time, coevolution has become one of the cornerstones of modern evolutionary biology. The species that lead to the discovery of coevolution was the Angraecum Sesquipedale, a variety of orchid with a spur extending over 30cm long. When Darwin received a sample from Madagascar containing this orchid he postulated that a moth with a proboscis of a similar length must exist to pollinate the orchid. In 1903 Xanthopan Morganii Praedicta was discovered, this moth, better known by its colloquial name, the Morgan Sphinx moth, …show more content…
Guild coevolution is much more common than specific coevolution, and though the interactions between the species are similar, they are necessarily more complex. A prime example of this is the interaction between the limber pine (Pinus flexilis), the American red squirrel (Tamiasciurus hudsonicus), and the Clark 's nutcracker (Nucifraga columbiana). The interaction between these three species is complex, with selective pressures on each species affecting the others. The limber pine and the American red squirrel participate in a predator/prey interaction, with the red squirrel preying upon the seeds dropped by the limber pine. In reaction to this limber pine populations in areas with red squirrels developed larger cones, with more scales and fewer seeds (Benkman). In area where squirrels are absent limber pines produce cones smaller scales and twice as many seeds (Benkman). However, this also makes it more difficult for Clark’s nutcracker, the limber pines primary seed disperser, to harvest seeds. The relationship between the limber pine and the Clark’s nutcracker is mutualistic with each gaining benefit from the other. The relationship between the American red squirrel and Clark’s nutcracker is one of interspecific competition for the same resource, namely the pine seeds. Clark’s nutcrackers generally harvest seeds from cones before they drop from the tree, but when the …show more content…
Escape and radiate coevolution necessitates the development of a trait or traits in one of the interacting species which provides an extreme advantage over the other and results in its rapid speciation into multiple lineages. The evolution of a particularly effective defense mechanism may render a species effectively immune to predation for a period of time, until a predator species counter-adapts in response, allowing for adaptive radiation unimpeded by predation (Futuyma). Escape and radiate coevolution is not confined to prey species however, predator species may also develop highly efficient traits which would allow them to freely exploit their prey species until they adapt to defend against it (Agrawal et al). The advantage that a species might develop would allow for a relatively short interval in which that species would experience adaptive radiation. However, eventually another species will counter-adapt to the focal species, and prevent further radiation

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