Question: How did Darwin come up with the theory that we started off as monkey that had a greater ancestor before?

Richard Unwin answered on 17 Nov 2015:

Hi again Megan!

The best evidence for evolution was collected by Darwin on a voyage to the Galapagos islands, aboard HMS Beagle. Here he noticed several very similar types of birds (since known as Darwin’s finches) but on different islands they had different shaped beaks and Darwin noticed it might be related to the types of seed that they ate in different places. Darwin speculated that they had ‘adapted’ from a single species with their beak shape changing over the generations to make them better suited to their environment. Once you’ve made that leap, you can stretch it our to suggest all species on the planet, including humans, evolved from a common ancestor to better live in their environment – to give themselves an advantage. It’s not necessarily true that we evolved from a modern-day chimp, but we and modern-day chimps evolved from the same (possibly now extinct) chimp-like species.

Strictly speaking, the idea that we were descended from apes wasn’t all Darwins – it had been suggested before but Darwin presented the best evidence and dared to back it up in public – at the time the church were very powerful and the idea that we weren’t created by God was seen as being very wrong. He caused quite a few arguments in his time!