Lll. a limited supply of necessary resources. If there isn't enough resources the species will have to learn to adapt to be able to gather the new food supply they need. Such as birds and there beaks, if the insects population went down and that was the main food supply for that type of bird they would have to be able to adapt in order to survive, so evolution occurs. Over time that bird would change to adapt to its new feeding source.
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The pericardium <span>is a double-walled sac containing the heart. The </span>pericardial<span> sac has two layers, a serous layer and a fibrous layer.</span>
The answer to the question is fumes