Isolation can be due to behavioral, geographical, or temporal barriers. <span>Speciation can take place in two general ways. A single species may change over time into a new form that is different enough to be considered a new species. This process is known as anagenesis. More commonly, a species may become split into two groups that no longer share the same gene pool. This process is known as cladogenesis. There are several ways in which anagenesis and cladogenesis may take place. In all cases, reproductive isolation occurs. Hope this helps! </span>
<span>A psychological response to an out-of-the-ordinary stressor defines the posttraumatic stress disorder (PTSD).
When people are exposed to a traumatic event, such as war, or sexual assault, or generally any type of threat or tragedy, they may develop PTSD as a result. This means that the person will still have strong and negative emotions, such as fear, or hatred, months or years after the event occurred, and it is very difficult to treat.
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The answer is A because it is not formed from decaying marine animals.
I think it is C but i am not completely positive.<span />
