Answer:
Migration is the movement of individual organisms into, or out of, a population. ... Immigration is the movement of individuals into a population from other areas. This increases the population size and growth rate. Emigration is the movement of individuals out of a population.
Explanation:
There can be many caused to the change of Earths temperature but one would be the use of fossil fuels. This is because when burned it releases Greenhouse gasses which are trapped in the atmosphere and causes heat. Which eventually leads to Global Warming. (Hopes this helps! )
The climate 250 mya was very tropical, so maybe those fossils could've been found there even w/o continental drift
Answer: A. Increasingly crowded urban areas
Explanation: Think about it this way. If you heard about more products being made in a city that means what? More jobs! Many people moved to cities and then made the cities unsanitary and many diseases spread around such as hepatitis. Anyways the more jobs there was the more money people could make and the more people lived in big cities like New York.