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: What type of ecosystem do polar bears live in? Answer: arctic

Answer: Polar Bears. Thick fur and a layer of blubber keep polar bears warm in their Arctic ecosystem. Why do you think their fur is white? Why might it be an adaptation in an Arctic biome?.

Question: Question: Which type of arthritis causes the immune system to attack joints? Answer: rheumatoid

Answer: In rheumatoid arthritis, the immune system attacks joints. This causes joint damage and pain.

Question: Question: What term refers to a change in species over time? Answer: evolution

Answer:
Evolution can be described as a change in species over time . Dinosaur fossils are significant evidence of evolution and of past life on Earth.