Question

Darwin hypothesized that new species could appear gradually through small changes in an ancestral species. What experiment did he conduct to test this hypothesis?

Answer 1

It was not an experiment that he did. It was just a series of observations over time (from historical knowledge as well) that brought him to this conclusion

Answer 2

The experiment that Darwin conducted to prove this hypothesis is known as the breeding of finches, which said that a new species can appear gradually.

Darwin observes Galápagos finches are a group of about 15 species of passerine birds. They are well known for their remarkable diversity in beak form and function.

How they look like they start as only one bird, and somehow they end un being about 15 species.

He studied them and concluded that everything starts with one species, and they spread and change adapting to that new environment.