What are two definitions of evolution, and why does evolution occur?

When the intestine becomes infected with the food borne illness bacteria e. coli, the bacteria releases a enterotoxin that causes excessive loss of water and electrolytes in the intestines. necessary to return the osmolality of the intestines to normal?

Researchers want to use edna to look for an invasive species in the water which of the steps would be likely do last

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