Selezione Naturale
Breve testo in inglese sulla selezione naturale di Darwin (2 pagine formato doc)
Natural Selection
With “Natural Selection” we mean “the gradual natural process by which biological traits become either more or less common in a population”.
How this selection works was published by Charles Darwin in “The Origin of the Species” in 1859.
In his book Darwin said that some different biological traits can be more useful for an animal, so the animal with that trait would be more suitable for the environment. So, in some years, the majority of that species would have that trait. He also said that the entity that would survive isn’t the strongest one, but the most suitable.
A famous example is the length of the giraffe’s neck. Darwin said that at the beginning all the giraffes had a short neck. Then, when the leaves on the trees became less, only the giraffes with a longer neck could eat, and so only they survived and then, when they reproduced, their sons would all have a longer neck. So, in a few generations, all the giraffe would have a longer neck.
The other main part of this theory is that Earth is older than Bible said.
For Christians Earth was created by God two or three hundred years before, but Darwin said that Earth had some billions years. This was a tough problem, because all the Christians were sure that only the Bible could tell the true about their planet.
Public reaction to this discovery changed during this period. At the beginning even the Christians accepted this theory, for example, Asa Gray, who was a biologist at Harvard, or Warfield, a conservative theologian.
But, after a century, a lot of Christians started to say that Darwin’s theory wasn’t the correct one, because in the Bible God had created
the Earth in 6 days and all the animals were already there.