Science & TechMental model
Evolution wants nothing. It only sorts.
A common mistake: species "develop" traits because they need them. In reality, variants arise at random and the environment sorts out which leave more offspring. Nothing strives upward, nothing is "more evolved". A bacterium fits its niche as well as you fit yours.
Useful: For any adaptation, ask who left more offspring with it, not what it's for.
Source: en.wikipedia.org