Answer: This is because small populations are more prone to disease, inbreeding may result in gentrified disorders, and captive species may not reproduce in the wild.
Hope this helps :)
Life is found almost everywhere on Earth, but it is not distributed evenly around the planet. Different species are found in different areas; some species have overlapping ranges, others do not. Each species has a set of environmental conditions within which it can best survive and reproduce. Not surprisingly, those conditions are the ones for which it is best adapted. Many different physical, abiotic (non- living) factors influence where species live, including temperature, humidity, soil chemistry, pH, salinity and oxygen levels.
Because they have less resources to fight off disease and nothing to use for immunity. Sub Sahara Africa is also very poor
D. think of it like a current!
electron -> electron-> electron->
