In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.
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Question: Question: Jim's skin was noticeably darker than his friend Matt's skin. This means that _____ produces more melanin. 
 Answer: Jim

Answer: However, the melanocytes of people with darker skin produce more melanin.


Question: Question: What would happen to the atmosphere as Jim climbed higher up a mountain? 
 Answer: it would become less dense

Answer: The density of the atmosphere decreases with an increase in the height above sea level (altitude).


Question: Question: Erin was going to see the elephants in the jungle. If the jungle is smaller than it was 20 years ago, then what has likely happened to the population of the elephants? 
 Answer: it has decreased

Answer:
The forest habitat of elephants has also decreased in size due to humans moving in, so the numbers of the elephants have decreased.