so speciaiton is the formation of new species, but there are two different ways, sympatric and allopatric, the thing is i don't understand how they can form new species, if you can provide some examples that would be great thanks!
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Sympatric speciation means a new species arises without geographic separation from the old species. Allopatric speciation means a new species arises while a population of the old species is geographically isolated from its parental species. Most oceanic species probably arose through sympatric speciation, since it would be difficult to isolate a marine species when there is no obvious barriers in an ocean. On land, however, a species of animal or plant may be isolated due to geological processes, and/or climatic changes For example, 2 populations of the same species of salamander may become isolated from one another on different mountains, if the valley between 2 mountains become too hot and/or arid to support any salamanders even though in the past there were salamanders in the valley because of favorable climate. Allopatry does not guarantee speciation, however. For example, some species, such as the California tiger salamander, has not evolved into a different species, even though it has been isolated for millions of years from the tiger salamanders of the rest of the United States. Recently, some tiger salamanders from outside California were accidentally introduced into California, and the native salamanders interbreed freely with the non-natives, showing that they have not evolved into different species. In contrast, the several species of western newts often breed in the same streams or ponds in California, but natural hybrids are very rare.
The evolution of human beings from an ape is probably an example of sympatric speciation, because there is no obvious geographic barriers which can isolate the first bipedal apes such as Ardipithecus, from their quadrupedal ancestors. Early hominids became adapted to the savanna and diverged from the apes by exploiting a different habitat, even if the two could have remained in contact with one another. In the beginning, when they were the same species, they were probably prevented from interbreeding because the apes defended their territories from the other apes. IOW, our ancestors were probably losers who were driven out of the forests because they lost their battles to stronger apes. They had to try to find a living in the savanna or face extinction. As our ancestors became adapted to living in the savanna, they probably could not interbreed with the apes because the hybrids would not be as good as the apes in exploiting the forests, but they were also not as good in surviving in the savanna since they were intermediate between 2 different animals living in two different habitats. Natural selection would then elminate the hybrids, and only those individuals who are capable of recognizing and breeding with their own kind could have survived. Millions of years later (and certainly much earlier than that), we no longer recognize our closest ape relatives as our own kind, and neither do they. That keeps us from interbreeding with the apes, making us and the apes separate biological species.
The evolution of human beings from an ape is probably an example of sympatric speciation, because there is no obvious geographic barriers which can isolate the first bipedal apes such as Ardipithecus, from their quadrupedal ancestors. Early hominids became adapted to the savanna and diverged from the apes by exploiting a different habitat, even if the two could have remained in contact with one another. In the beginning, when they were the same species, they were probably prevented from interbreeding because the apes defended their territories from the other apes. IOW, our ancestors were probably losers who were driven out of the forests because they lost their battles to stronger apes. They had to try to find a living in the savanna or face extinction. As our ancestors became adapted to living in the savanna, they probably could not interbreed with the apes because the hybrids would not be as good as the apes in exploiting the forests, but they were also not as good in surviving in the savanna since they were intermediate between 2 different animals living in two different habitats. Natural selection would then elminate the hybrids, and only those individuals who are capable of recognizing and breeding with their own kind could have survived. Millions of years later (and certainly much earlier than that), we no longer recognize our closest ape relatives as our own kind, and neither do they. That keeps us from interbreeding with the apes, making us and the apes separate biological species.