Board Thread:Clubs/@comment-174.2.24.208-20190531012445/@comment-38374359-20190628140052

^That's not quite how evolution is believed to work. It's not gaining new DNA, per se. It's like there are a bunch of animals. Some are smarter than others, not by a lot, but just a bit. The dumber ones will tend to get killed because they aren't as good at finding food and hiding from predators. So the smart ones have babies, which are also smart because of their parents' DNA. And let's say this generation also has the natural mix of some animals smarter, some dumber, but the average intelligence is a bit higher. And the dumb ones die and the smart ones have babies. And the cycle repeats while the average intelligence gets very slightly higher with each generation.

And for stuff like the addition of eyes, I think it's often believed to be accidental mutations in DNA that turn out to be beneficial and are passed on and give animals slight advantages over others.