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: Dan notices that there were no new trees planted this year. Since there are so few trees in the area, Dan expects the air to be 
 Answer: dry

Answer: With fewer trees, the air is drier and droughts are more common.


Question: Question: If there are very few wolves the deer population will 
 Answer: increase

Answer: An increase in predators, the emergence of a new disease, or the loss of habitat are just three possible problems that will decrease a population.


Question: Question: We shiver when it is cold because it allows us to produce 
 Answer: more heat

Answer:
For example, on a cold day, an endotherm may produce more body heat by increasing its rate of metabolism.