کسی از دوستان این رو ترجمه میکنه؟(با تلخیص هم اشکالی نداره)The first thing that is important to remember is that evolution is only a process, and doesn't have a mind. Evolution never "thinks" or "decides" anything; it is only a consequence of simple mathematical laws and the constraints of a limited environment. The next thing to remember is that individual organisms don't evolve: populations evolve. Any change that happens within an individual animal is not evolution. Evolution is the change that happens to a whole population over many generations. Evolution occurs because not every individual is identical. Some individuals may possess traits that make them more likely to survive and have more offspring, and others may possess traits that make them less likely to survive and have offspring. In the next generation, the individuals with the more beneficial traits will have had more children, and so the more beneficial traits will be more common. Over many generations, the more beneficial traits become universal, and the less beneficial traits vanish. This is called natural selection.
The other thing that can be confusing is that in biology, the word "adapt" has several different meanings that may seem similar but actually aren't especially closely related. One sense of the word "adapt" relates to a change in the individual. For example, if I spend a long time in a cold environment, eventually my body's physiology will change to tolerate it better, and I will adapt to the cold. But as I said above, changes in the individual are not evolution, and this is not the sense meant by an evolutionary adaptation. In evolution, a population might adapt to the cold if initially there are some individuals that have a trait that lets them tolerate it, for example, a thick fur coat. Individuals without the thick fur coat will die in cold weather, leaving only those with the thick coat to survive and reproduce. After many generations, all the individuals in the population will have the thick fur coat, and the population has adapted to the cold, and the thick coat is said to be an adaptation.
So now we're ready to tackle your question with an example. Suppose we have a population of bugs that live on tree trunks, and that are preyed upon by a population of birds. Initially, the bugs are mostly bright red, but there's some variation; some are a little bit brighter than the others, and some are a little bit duller and browner. When the birds go hunting for their daily meal, they can see the bright red bugs easily against the tree trunks, and they eat them. At first, they have no trouble seeing any of the bugs, but the brightest bugs are the easiest to see, so they eat them first. Even the dullest, brownest bugs are still pretty bright, but by the time the birds have eaten the brighter bugs, they're full, so the dullest bugs survive and reproduce. In the next generation, there is again some variation in the color of the bugs, but the average color is a bit duller than in the parents' generation. Again, the birds eat the brightest bugs, and the dullest survive. After many generations of this repeating, the bugs in the population are no longer red, but brown, and blend in nicely with the tree bark.
You can imagine another population of similar bugs that live not on the tree trunks, but in the leaves. Now the greener bugs have an advantage, and over many generations, all the bugs will be green. You can also imagine the same thing happening with shape instead of color; initially, all the bugs are just round, but some are a little rumpled and slightly bark-shaped, or leaf-shaped, and so are a little bit harder to see than the other bugs. After enough generations, the bugs come to blend in very well with their surroundings.
So you can see that natural selection doesn't need to think of anything, and individual animals don't need to change for evolution to happen. It's all due to variation and natural selection. I hope this helped!
تنبل شدن بیش از حدم به خاطر بهار هست حال ندارم حتی جواب عادی بدم چه برس به ترجمه:))
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