Inbreeding Flashcards
What is Homozygosity ?
When an individual has two copies of the same allele at the loci.
Where are Rare alleles found more commonly? And what is a common trait?
In inbred populations.
They are often Deleterious.
What are the effects of deleterious alleles?
Negative effects on reproduction and survival.
What is the inbreeding coefficient?
The probability that both alleles at a locus are identical by descent.
Number range from 0 (outbred) to 1 (inbred).
How are levels of inbreeding measured?
Relative to base populations.
What does Genomics measure?
How homozygous an individual is?
Why does inbreeding tend to occur in small populations?
There are fewer individuals meaning a higher frequency of rare alleles.
How do you measure the number of ancestors?
2t
t=no. of generations since the population was founded.
What are the characteristics of inbreeding depression?
Adverse effects include anything that will effect survival and reproduction:
Juvenile survival
Longevity
mating ability
Sperm quantity and quality
etc.
E.g. White tigers
What happens when growth rates fall below 0?
Recovery will be slower and resilience to impacts will be reduced which can lead to extinctions. As a result Reproduction and survival will be affected.
What is parthenogenesis?
The ability to conceive offspring without a partner. ‘Virgin birth’.
E.g. Desert topminnow in the Platanos Creek in Sonora Mexico.
How was inbreeding within the top minnow population reversed in 1985?
Individuals from different pools were brought together and the sexual minnows (males and females) reformed 80% of the population.
What is genetic rescue? And what can it do?
The translocation of individuals from an outbred population to an inbred one. This can eliminate inbreeding depressions (e.g. Swedish adder).
How is inbreeding in natural populations measured?
Using molecular markers under identical conditions.
What is sigma when measuring inbreeding depression?
The proportionate decline in phenotypic traits due to inbreeding.