mutation accumulation
Woodworth LM, Montgomery ME, Briscoe DA & Frankham R 2002 Rapid genetic deterioration in captive populations: causes and conservation implications. Conserv Genet 3:277-288.
- inbreeding depression and genetic adaptation were responsible for the genetic deterioration in 'wild' fitness
- genetic deterioration in captivity is likely to be a major problem when long-term captive bred populations of endangered species are returned to the wild
- tests for effects of mutational accumulations in our populations have been reported previously, and revealed no detectable contributions over 45–50 generations (Gilligan et al. 1997)
- there were no detectable effects of mutational accumulation in our populations (Gilligan et al. 1997)
- we concentrate on the impacts of inbreeding depression and genetic adaptation to captivity
- in Drosophila, Shabalina et al. (1997) reported similar declines in fitness to those in our large populations maintained under benign conditions, but evaluated under crowded conditions
- their populations with Ne ~ 400 showed a 2% decline in fitness per generation over 30 generations
- compared to 1.7% per generation over 50 generations in our Ne = 500s
- they attributed the fitness declines in their populations to mutational accumulation
- they did not have the range of Ne treatments and controls required to exclude genetic adaptation as the explanation
- they did not carry out specific tests for increased loads of mutations
- given the close similarity in experimental details and results, their genetic deterioration was most probably due to genetic adaptation to benign conditions being deleterious under crowded conditions
- rather than mutational accumulation
- genetic adaptation of endangered species in captivity may be of much greater concern than hitherto recognised
