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.
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Question: Question: Predators can replace what tool in agriculture. Answer: pesticides

Answer: Predator species such as birds and spiders control insect pests. They reduce the need for chemical pesticides, which are expensive and may be harmful to human beings and other organisms.

Question: Question: How can you calculate the density of matter? Answer: by dividing its mass by its volume

Answer: The density of matter can be calculated by dividing its mass by its volume.

Question: Question: What do we call structures that have lost their use through evolution, which serve as important evidence of evolution? Answer: vestigial

Answer:
Vestigial structures, or structures that have lost their use through evolution, are important evidence of evolution.