Mainly because it was extremely hot at the beginning of Earth's time.
<span>There are numerous reasons why. For example, you can be afraid that if the case isn't solved that the person might hurt you, or that their family might hurt you. Another might be that the people who you report them too work together with them so they might turn it on your head. Also, they might set you up if they all work together.</span>
One of the changes in development and specialization that did not happen in primitive mammals was the increase in stomach capacity. The specialization of teeth and the lower jaw are two important modifications of the primitive mammals. Also an increase in size and brain capacity are two crucial modifications of the early mammals.