Natural Selection is the process by which individual organisms with favorable traits are more likely to survive and reproduce than those with unfavorable traits. It works on the whole individual, but only the heritable component of a trait will be passed on to the offspring, with the result that favorable, heritable traits become more common in the next generation. Given enough time, this passive process results in adaptations and speciation by Charles Darwin.Darwin's Finches
On his journey to Galapagos Island by Beagle, Darwin have found a specie on which he discovered the theory of Natural Selection.
Darwin was especially intrigued by one group of birds, the finches. The 13 species of Galapagos finches live nowhere else in the world. One island was found to contain several species. Each species of has a particular type of beak, which is suited to a certain kind of food. His observation of the finches were to become one of the strongest arguments for the role of natural selection in the origin of species - and today the finches are still considered to be a classic example of evolution.
On his journey to Galapagos Island by Beagle, Darwin have found a specie on which he discovered the theory of Natural Selection.
Darwin was especially intrigued by one group of birds, the finches. The 13 species of Galapagos finches live nowhere else in the world. One island was found to contain several species. Each species of has a particular type of beak, which is suited to a certain kind of food. His observation of the finches were to become one of the strongest arguments for the role of natural selection in the origin of species - and today the finches are still considered to be a classic example of evolution.
Although the different genera and species of finches are identified mainly by differences in beak shape and feeding habits, they are basically alike.
The tree finch, found in the forest zone, has a short, thick beak and feeds mainly on insects taken from the bark of trees and also on seeds. The ground finch and warbler finch are found on all the islands. The cactus ground finch has a long slender beak and feeds on the flowers of the prickly pear. The large ground finch has a blunt, powerful beak for breaking open hard seeds. It also eats flowers, fruits and some insects. It can eat bigger seeds than the other ground finches. The warbler finch has a slender beak and feeds only on insects.
Darwin noticed that each species of finch had a different shape or size of beak. Bird's beaks are like tools - different ones are suited to different jobs. Beaks of different shapes are adapted to eating different kinds of food.
Darwin felt that it was too much of a coincidence to assume that all 13 species had been separately created to be so basically alike. He believed that it all started with one kind of finch arriving from the Soth American mainland and that evolution working over millions of years had resulted in the 13 species.
Summary of Natural Selection:Darwin felt that it was too much of a coincidence to assume that all 13 species had been separately created to be so basically alike. He believed that it all started with one kind of finch arriving from the Soth American mainland and that evolution working over millions of years had resulted in the 13 species.
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