Fossils reveal ecological relationships from the past- how do we know when the moth species Stigmella heteromelis was alive, even though we do not have fossils of the moth or caterpillar?

How can you approximate the number of calories required to keep you in energy balance?

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

Most animal cells membranes have proteins that pump ions out of the cell and potassium ions into the cell