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- It is not certain the cause of this however it is said that due to the environmental stress, a shortage of food, and the hunting of these animals.
- Their genetic variation decreased drastically and to this day it is low. Inbreeding increased because the random selection of surviving cheetahs were forced to mate with close relatives, resulting in lowered heterozygosity, increased genetic load, and increased expression of deleterious alleles.
- Is there a way to test the degree of inbreeding?
- There is indeed. Usually it involves transplanting a piece of skin from one cheetah onto another trying to determine if the graft is accepted easily. Another way to tell is through the study of their skulls. Some museum collections showed that their skulls are quite asymmetrical if they are inbred.
- Yes, in fact they have! Does anyone want to explain to the rest of us what a bottleneck effect is?
- Did they face any bottleneck events because that’s what we were learning in class?
- It occurs when a population decreases in size all of a sudden. Which can be due to natural catastrophes or because of humans.
- Every population experiences genetic drift, but small populations feel its effects more strongly. Genetic drift does consider an allele’s adaptive value to a population. It may cause a loss of a beneficial allele or fixation of a harmful allele in a population.
- That's enough of bombarding you guys with information about cheetahs. What about we go look at some other cool animals.
- We got extinct nearly 10,000 years ago (our second bottleneck event), around the time of the last ice age. My friends from North America and Europe went extinct.
- Was there a reason for this, sir?
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