The chart below shows some events in earth's history and the primary sources of information which were examined to date the events. earth event marine animals appear fuel sources appear mammals appear ferns appear primary source of information history books fossil in rocks green plants root structures which of these earth events was dated using the most valid and reliable source of information? marine animals appear fuel sources appear mammals appear ferns appear

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How are mutations continually being generated in a population (what are some of the causes of mutatuions? ) explain

1. emigration the movement of people from one place to another 2. immigration a situation in which resources are being used up at a faster rate than they can be replenished 3. migration the leaving of one's homeland to settle in a new place 4. overpopulation the movement of people to a new country 5. sustainable development a situation in which the birth rate is not sufficient to replace the existing population 6. underpopulation the ability to meet current needs without reducing the ability to meet future needs 7. unsustainable development the increase in the population of a city 8. urbanization a situation in which the number of people exceeds the available natural resources in an area