do u ppl believe in evolution??? we were learning about it in school but its just hard to believe. i know that the animal itself doesnt change but the population. but there is NO way that animals like whales were land animals and evolved!!!! how can i study it if i dont even believe it?!
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Dont forget- this doesn't happen over a few generations. It happens over MANY MANY MANY generations and MILLIONS of years. Do some quick math- if an organism reproduces every 10 years and it takes 1 million years to see a change, then that is 100,000 generations.. that's a LOT of time to have mutations and natural selection.
The theory of evolution by natural selection sometimes needs to be an "Aha!" moment by students for them to really get it. Just try understanding the concepts behind it, and then really think about the length of time and number of generations involved. This isn't something you would see in your lifetime in most cases.
Although- look at some of the examples in your text. There is a moth one about moth's in areas with darker trees selecting darker and darker moths (lighter ones get eaten and don't get a chance to reproduce) while lighter treed forests end up with lighter moths (darker moths can't hide and get eaten so they can't reproduce). Although it is a very minor change, it IS evolution by natural selection. If this continued for many more generations, you might end up with two different species- they wouldn't willingly mate with each other because maybe they look to different.
Good luck. :)
The theory of evolution by natural selection sometimes needs to be an "Aha!" moment by students for them to really get it. Just try understanding the concepts behind it, and then really think about the length of time and number of generations involved. This isn't something you would see in your lifetime in most cases.
Although- look at some of the examples in your text. There is a moth one about moth's in areas with darker trees selecting darker and darker moths (lighter ones get eaten and don't get a chance to reproduce) while lighter treed forests end up with lighter moths (darker moths can't hide and get eaten so they can't reproduce). Although it is a very minor change, it IS evolution by natural selection. If this continued for many more generations, you might end up with two different species- they wouldn't willingly mate with each other because maybe they look to different.
Good luck. :)
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Well you could investigate a little bit. I read about a scientist who raised e. Coli. During 20 years. Around generation 30,000 if I ain't wrong they developed the ability to metabolize citrate, which is quintissential as the lack of citrate metabolization is what defines e. Coli as a specie. This is an example of genetic mutations in a populations. What is best is that this guy kept frozen e coli every 500 generations and he could repeat the experiment over and over after generation 20,000. You also have the example of a population of moths who grew near london. They were normally white because darjer tones were easily preyed upon, but after the industrial revolution pollution killed the moss on trees which turned them darker thus making white moths easier to prey upon as they lived on the trees. This is an example of natural selection. Then we have the fossil record which shows a steady progression of organisms as we dig deeper. We also have the human beings which with subsequent generations become less an less hairy. If you observe the world with an open mind you would notice that not believing that evolution indeed takes place is idiotic.