TY - JOUR
T1 - Modeling problems in conservation genetics using captive Drosophila populations
T2 - consequences of equalization of family sizes
AU - Borlase, Suzanne C.
AU - Loebel, David A.
AU - Frankham, Richard
AU - Nurthen, Roderick K.
AU - Briscoe, David A.
AU - Daggard, Grant E.
PY - 1993
Y1 - 1993
N2 - Equalization of family sizes is recommended for use in captive breeding
programs, as it is predicted to double effective population sizes,
reduce inbreeding, and slow the loss of genetic variation. The effects
of maintaining small captive populations with equalization of family
sizes versus random choice of parents on levels of inbreeding genetic
variation, reproductive fitness, and effective population sizes (Ne)
were evaluated in 10 lines of each treatment maintained with four pairs
of parents per generation. The mean inbreeding coefficient (F)
increased at a significantly slower rate with equalization than with
random choice (means of 0.35 and 0.44 at generation 10). Average
heterozygosities at generation 10, based on six polymorphic enzyme loci,
were significantly higher with equalization (0.149) than with random
choice (0.085), compared to the generation 0 level of 0.188. The
competitive index measure of reproductive fitness at generation 11 was
more than twice as high with equalization as with random choice, both
being much lower than in the outbred base population. There was
considerable variation among replicate lines within treatments in all
the above measures and considerable overlap between lines from the two
treatments. Estimates of Ne for equalization were
greater than those for random choice, whether estimated from changes in
average heterozygosities or from changes in F. Equalization of family sizes can be unequivocally recommended for use in the genetic management of captive populations.
AB - Equalization of family sizes is recommended for use in captive breeding
programs, as it is predicted to double effective population sizes,
reduce inbreeding, and slow the loss of genetic variation. The effects
of maintaining small captive populations with equalization of family
sizes versus random choice of parents on levels of inbreeding genetic
variation, reproductive fitness, and effective population sizes (Ne)
were evaluated in 10 lines of each treatment maintained with four pairs
of parents per generation. The mean inbreeding coefficient (F)
increased at a significantly slower rate with equalization than with
random choice (means of 0.35 and 0.44 at generation 10). Average
heterozygosities at generation 10, based on six polymorphic enzyme loci,
were significantly higher with equalization (0.149) than with random
choice (0.085), compared to the generation 0 level of 0.188. The
competitive index measure of reproductive fitness at generation 11 was
more than twice as high with equalization as with random choice, both
being much lower than in the outbred base population. There was
considerable variation among replicate lines within treatments in all
the above measures and considerable overlap between lines from the two
treatments. Estimates of Ne for equalization were
greater than those for random choice, whether estimated from changes in
average heterozygosities or from changes in F. Equalization of family sizes can be unequivocally recommended for use in the genetic management of captive populations.
UR - http://www.scopus.com/inward/record.url?scp=0027380952&partnerID=8YFLogxK
U2 - 10.1046/j.1523-1739.1993.07010122.x
DO - 10.1046/j.1523-1739.1993.07010122.x
M3 - Article
AN - SCOPUS:0027380952
SN - 0888-8892
VL - 7
SP - 122
EP - 131
JO - Conservation Biology
JF - Conservation Biology
IS - 1
ER -