What is 'differential breeding success'?

Question

NOT a homework question. Just part of an answer to another question of mine. So sensible answers appreciated :-)

Answer 1

It just means that some organisms will have more success in breeding than others. This is one of the fundamental parts of the theory of evolution.

Basically, the idea is that the organisms that are more suited to the environment will have a better chance of reproducing. This is either because they are more likely to survive to the age of reproduction, or because they are able to attract a mate more easily. Therefore on average they will leave more descendants than other organisms who aren't so well-adapted.

This is what is meant by natural selection - it's often misunderstood as meaning "survival of the fittest", but really it is about who leaves the most descendants relative to the rest of the population.

By the way, I would have said "differential reproductive success" rather than "breeding", but I suppose that's just a matter of semantics.