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evolution Anonymous
Not really familiar with the literature, but I've been wondering, since it's not possible to observe evolution because it takes thousands of years and generations, what about organisms which have a very short lifespan and reproduce frequently, which could mean hundreds of generations in less than a year?
I forget what they are, but there was one or two insects that live and die in 24 hours?
So, for example, if you took a sample of those and placed them in an enclosed, controlled but natural environment, replicating their natural habitat but altering it in some way, like the type/ colour of plants, food, predators, temperature, humidity etc, then observe over the course of a year whether down the line the organisms have been adapted to that changed environment?

Just a little confused about the issue of evidence of evolution, and wondering if this kind of thing would work or not, and whether or not they already tried it. Sorry if it sounds stupid or inappropriate.
>> Anonymous
>since it's not possible to observe evolution because it takes thousands of years

Not really correct, since natural selection as we observe it change organisms IS evolution.

We can readily observe bacteria, for example, evolve on the short term. Shit, a species of moth in Britain has adapted (read: evolved) to take advantage of the more polluted environment.
>> Anonymous
>>282936
Indeed... I was just trying to think about more objective methods, which the people who call themselves intelligent but don't accept evolution could acknowledge, I guess.
>> Anonymous
>>282954
Referring to your post specifically, I think that fruit flies are fequently used for that sort of study, due to their simplicity and short lifespans.
>> Anonymous
>>282955
rly? I think fruit flies are used to demonstrate mendelian genetics . . . but isn't evolution a change in species? never heard of that result . . . then again, I am no biologist
>> Anonymous
reported, get the fuck out.
>> Anonymous
>>282959
also, what is the appropriate point at which we can say evolution takes place? certainly, evolution comprises more than structural and genetic changes (adaptations). changes in behavior also count, no?
>> Anonymous
>>282960
not intimidated, shut the fuck up
>> Anonymous
>>282926

Two words: antibiotic resistance.
>> Anonymous
>>282954
How about sterilization for them. In two generations, half the stupidity in the gene pool would have been cleansed.
>> noko
>>282963

evolution is ONLY a genetic change in an entire population. If there is no genetic change, it is not evolution, rather it would be adaptation (which isn't necessarily genetically expressed).
>> Anonymous
>>282936
Scientists are still discussing about the industrial melanism of Biston betularia, don't believe your statement to be 100% true.
>> Dr. Grissom !9GXd8p7Kds
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Yes there have been many genetics studies from the 1940-1960's with different Drosophila species, mainly Drosophila melanogaster. Several of those tests produced some very strange results.


Depending on your definition of a species, many new "species" were created in that time period. If you believe "a population of isolated reproducing individuals" is a species, some of the mutations that were bred out by scientists involved mating behavior/mating preferential/sex organs and so on. Strains were artificially selected to the point that they would no longer mate with the original wild type Drosophila. In this sense they were "new" species because they only bred with the highly inbred relatives that shared the same odd mutation. However, many of these had such extreme malformities that they would never survive in the wild.

An example of this is the image, called ultrabithorax, a mutation that resulted in the 3rd thoracic segment to be replaced by a duplicate of the 2nd. It is estimated that about 100 million years ago, flies lost their second pair of wings.

http://en.wikipedia.org/wiki/Hox_genes

Another good example of evolution we have actively witnessed in the lab is P element, a transposon that appeared in a D melanogaster lab mid 20th century, and has since spread to all known wild populations of D. melanogaster. Though, the wiki article does not read easy....

http://en.wikipedia.org/wiki/P_element
>> Fruit Flys Drew
Yes. They do those kind of experiments with fruit flys.
>> Anonymous
>>282926

Glad to see somebody is taking an interest in evolution.

Firstable, we do have peer-reviewed documents about observed instances of speciations (macro evolutions). If you are interested, here is a link: www.talkorigins.org.

Second, great example of what you are describing would be bacteria which evolves everytime. They are reproduce every 10~20 min depends on the environment. If a single bacteria, size of a human reproduces, in 24 hours, you wouldn't be even get out of the bed (just a little story I heard from microbiology teacher. He had great sense of humor. It's a bit exaggerated but it demonstrates how fast they can reproduce in such a short time). 'Superbug' is the result of our overly clean environment which it evolved to contain genes that can resists multiple drugs.
>> That Gomez
well what if we took the controlled environment idea, and watched as flies bred, taking out only ones with certain traits, like, a slightly different color, or smaller wings. Would that be mandellian or encourage evolution?
>> Anonymous
Stalk-eyed flies anyone?
textbook
>> Anonymous
http://www.newscientist.com/channel/life/dn14094-bacteria-make-major-evolutionary-shift-in-the-lab.h
tml

Reproducible Speciation.