Could emigration or immigration have played a major role in determining the size of the reindeer population? Explain. Think about where these reindeer were and whether they could swim that far

Yes.

Explanation:

Yes, emigration or immigration have played a major role in determining the size of the reindeer  population in specific area because immigration is done by the animals in search of food. The animals moves from one region to another in search of food so due to this movement the population of reindeer decreases in that specific area. Reindeer are good swimmers so due to this ability they cross the vast Yukon River which is half mile wide.

the answer is; comparing the frequency of collisions with and without the device

this makes the anti-collision system an independent variable and the collisions a dependent variable. if there are fewer collisions with an anti-collision system that without, then it can be stated that the system is a success. essentially, collisions under an anti-collision system are compared with the frequency of collisions by cars with the human drivers.

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.