Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

[Q]: Question: What phenomenon is crowding out other species and making all the other causes of extinction worse? Answer: human overpopulation
[A]: Human overpopulation, which is crowding out other species. It also makes all the other causes of extinction worse.

[Q]: Question: Where are the seeds in gymnosperms found? Answer: in cones
[A]: Gymnosperms have seeds, but they do not produce fruit. Instead, the seeds of gymnosperms are usually found in cones.

[Q]: Question: What do we call the movement of individuals into a population from other areas? Answer: immigration
[A]:
Immigration is the movement of individuals into a population from other areas. This increases the population size and growth rate.