Darwin hypothesized that new species could appear gradually through small changes in an ancestral species. Which observation that he made about finches most supports that hypothesis?
Answers
Adaptive radiation: Darwin's finches:
In September 1835, Charles Darwin stepped on the edge of the Galápagos archipelago, this was the beginning of five weeks, which would change the world of science, although he did not know it at the time. In other searches, he saw and collected small birds living in the islands but they did not realize their importance, and failed to keep good records of their sample and where they were collected. It was not as long as he was not back in London, the birds were disturbed, that the realization that they were all different, but closely related, the species of finch forwarded them to prepare the theory of natural selection.
In his memoirs, The Voyage of the Beagle, Darwin noted, almost as a form of fear, "someone can actually imagine that, by the original deficiency of birds in this archipelago, one species was taken for different ends And was revised. "
Actually, the Galapagos is called a living laboratory where species can be seen at work. Some million years ago, a species of Finch moved from the mainland of the Middle or South American to the Rocky Galapagos Many migratory species come from this - at least 13 species that grow from an ancestor.
This process in which one species gives birth to different species, which exploits different niches are called adaptive radiations. Ecological nail selections put pressure on which push the population in different directions. On different islands, finch species have been adapted for different species: seeds, insects, flowers, seawater blood, and leaves.
Paternal finch was a land-dwelling, seed-eating finch. After the explosion of species in the Galapagos, there will be a total of 14 species: three species of land-eaters; Three live on cactus and eat seeds; Living in a tree and eating seeds; And 7 species of tree-dwelling insects.
Darwin spent many years trying to understand the process, which was mainly different from the size and shape of his beak.
Recently, Peter and Rosemary Grant have spent many years in the Galápagos, due to the annual climate change dramatically changing the food supply. As a result, some composts live or die, depending on which species the peak structure was most favorable for the most abundant food - such as Darwin had predicted.
Changes in ancestral species gives new species according to Darwin:
Darwin was famous ecologist and is well known for his “contribution in study of evolution”. During his experiment with finch birds, Darwin observed that all the Finches appeared to be related to each other but showed variation when they were compared with the mainland population.
This made Darwin to hypothesize that “new species could appear gradually through few changes in an ancestral species”. The variation shown by the finch population supported Darwin’s hypothesis stating the offspring may exhibit variation from the ancestors.