Lecture 27

Question 1

can loss of genetic variation cause extinction?

Answer 1

loss of genetic variation can be a secondary or even primary cause of extinction.

Question 2

what are the two main genetic effects that can lead to population decline?

Answer 2

• non random mating including inbreeding depression and hybridization
• loss of adaptive potential whic may be due to loss of genetic (additive) variation and increase in genetic drift

Question 3

How can populations respond to habitat degregdation, three ways?

Answer 3

1. phenotypic plasiticity (individual changes in behavior or physiology) such as changing the timing of budding. this enables rapid response but thw range of the response is limited
2. migration. many species can change their ranges, but some species need to continously shift ranges and this is prevented by insurmountable barriers
3. Genetic adaptation. many populations and species are adapting genetically to anthropogenic changes (ex. heavy metal tolerance) but some environmental change is too rapid for many species to adapt, especiallt those with low fecundity and/or long generation times

Question 4

what is an extinction vortex?

Answer 4

A vortex is a result of an increase in the impact of genetic drift on the population, due to the population’s decreased size. This corresponds with a decrease in genetic variance which leads to a decrease in “population adaptive potential”, and eventual extinction.

Question 5

What is the primary goal of conservation?

Answer 5

the primary goal of conservation must be the maintenance of the potential for populations to adapt to these human activity changes

Question 6

True or False: genetic tools can also aid other aspects of conservation

Answer 6

true

Question 7

what is conservation genetics?

Answer 7

the application of genetics to understand and reduce the risk of population and species extinctions.