2006-11-21 02:53:01 · 12 answers · asked by peter_webster2001 1 in Science & Mathematics ➔ Biology
Speciation is the evolutionary process by which new biological species arise. There are four modes of natural speciation, based on the extent to which speciating populations are geographically isolated from one another: allopatric, peripatric, parapatric, and sympatric. Speciation may also be induced artificially, through animal husbandry or laboratory experiments.
There are many means for an organism to split into two species. When this happens, it doesn't mean that one organism ceases to exist. For example, when nectarines were bred using peach stock, it doesn't mean that peaches no longer exist.
During allopatric speciation, a population splits into two geographically isolated allopatric populations (for example, by habitat fragmentation due to geographical change such as mountain building or social change such as emigration). The isolated populations then undergo genotypic and/or phenotypic divergence as they (a) become subjected to dissimilar selective pressures or (b) they independently undergo genetic drift. When the populations come back into contact, they have evolved such that they are reproductively isolated and are no longer capable of exchanging genes.
2006-11-21 03:04:47 · answer #1 · answered by DanE 7 · 1⤊ 1⤋
Human did not evolve from apes . The human and apes were different species since 2 millions years
2006-11-21 10:57:49 · answer #2 · answered by maussy 7 · 0⤊ 0⤋
Humans idn't evolve from apes, they shared a common ancestor.
Congrats, I hadn't posted this answer in like 4 or 5 days, I had begun to think that people had maybe actually tried learning about evolution before swallowing the blue pill and dismissing it (then attempting to attack it on yahoo answers....)
My faith has been restored.
2006-11-21 13:42:28 · answer #3 · answered by John V 4 · 0⤊ 0⤋
Think of it this way...take a bunch of monkeys and separate them into two groups, separated across the earth. Then let a couple million years pass without them interacting. Each group is in a different environment. Assuming that the monkeys that are weakest will die, and the environment is different in both places, then the traits that are beneficial to monkeys will cause them to survive more.
If there is higher pressure of killing off weak/un-adapted monkeys then you are likely to have more changed monkeys left...those that have some genetic change that adapts them to the environment.
Put these two groups back together after all that and you'll have completely different appearances...like monkeys and humans. It seems like a long stretch, but over the huge amounts of time relevant here it is easy to accomplish.
2006-11-21 11:55:12 · answer #4 · answered by liegelr 2 · 0⤊ 0⤋
Humans diverged from apes (our closest relative is the chimp). When speciation occured (at point of divergence = 2 sperate species that could not cross breed resulting in viable offspring) then each species continued to evolve as a seperate species. The sperate species could not crossbreed.
2006-11-21 15:22:39 · answer #5 · answered by nokhada5 4 · 0⤊ 0⤋
same question that gets asked again and again and again and again - are you a machine maybe, I mean a program from Yahoo!
anyway, we all evolved from unicellular organisms, and they are still around (and constitute, by far, the largest part of the total mass of living organisms on the planet).
evolution does not have to mean that something totally replaces another. it often means that among a given population of something, one part acquires a different characteristic, and at one point ends up being very different from the original starting point.
it is a bit as if you said, that small branch grew from that tree, so why is the trunk still there?
2006-11-21 12:19:01 · answer #6 · answered by AntoineBachmann 5 · 1⤊ 0⤋
just becasue we eveolved from them does not mean they magicaly poof
not every ape evolved into humans
only a certain few did at a specific time and place
2006-11-21 10:56:56 · answer #7 · answered by Anonymous · 0⤊ 1⤋
Sameja is right--theories are useless. Why, just look at that stupid Theory of Gravity--what nonsense. Everybody knows we stick to the Earth because of static electricity.
2006-11-21 11:26:01 · answer #8 · answered by Amy F 5 · 2⤊ 0⤋
becuz humanz did not evolve from apes lol and the theory of evolution is not correct and shouldnt even be used since Science is about proving things and the THEORY isnt proven
2006-11-21 10:56:47 · answer #9 · answered by Anonymous · 0⤊ 4⤋
why do you assume that evolution means everything is supposed to become "human-like"
2006-11-21 12:21:51 · answer #10 · answered by Nick F 6 · 0⤊ 0⤋