TY - JOUR
T1 - Life-history phenotypes in a live-bearing fish Brachyrhaphis episcopi living under different predator regimes
T2 - Seasonal effects?
AU - Jennions, Michael D.
AU - Wong, Bob B.M.
AU - Cowling, Ann
AU - Donnelly, Christine
PY - 2006/8
Y1 - 2006/8
N2 - Several key life-history attributes in a tropical live-bearing fish, Brachyrhaphis episcopi, have previously been shown to differ between populations that co-occur with large predatory fish (Characin sites) and those that do not (Rivulus sites). Here we show that differences between Characin and Rivulus localities are also repeatable over time; patterns observed in the wet season also persisted during the dry. Both sexes reached maturity at a smaller size at Characin sites. Although there was no difference in fecundity between larger females living in different predator communities, smaller females at Characin sites produced more offspring. Females also produced smaller offspring at Characin localities. These differences are remarkably similar to those reported in two other species of live-bearing fish, B. rhabdophora and Poecilia reticulata suggesting possible convergent adaptation in life-history strategies due to predator-mediated effects or correlates thereof. We also found seasonal changes in life-history traits that were independent of predator community. In the wet season, mature males were larger, females allocated more to reproduction, and offspring mass was also greater. The results of our study generate testable predictions using B. episcopi to further our understanding of life-history evolution.
AB - Several key life-history attributes in a tropical live-bearing fish, Brachyrhaphis episcopi, have previously been shown to differ between populations that co-occur with large predatory fish (Characin sites) and those that do not (Rivulus sites). Here we show that differences between Characin and Rivulus localities are also repeatable over time; patterns observed in the wet season also persisted during the dry. Both sexes reached maturity at a smaller size at Characin sites. Although there was no difference in fecundity between larger females living in different predator communities, smaller females at Characin sites produced more offspring. Females also produced smaller offspring at Characin localities. These differences are remarkably similar to those reported in two other species of live-bearing fish, B. rhabdophora and Poecilia reticulata suggesting possible convergent adaptation in life-history strategies due to predator-mediated effects or correlates thereof. We also found seasonal changes in life-history traits that were independent of predator community. In the wet season, mature males were larger, females allocated more to reproduction, and offspring mass was also greater. The results of our study generate testable predictions using B. episcopi to further our understanding of life-history evolution.
KW - Convergent evolution
KW - Guppy
KW - Life-history strategy
KW - Predation
KW - Reproduction
KW - Seasonality
UR - http://www.scopus.com/inward/record.url?scp=33748503168&partnerID=8YFLogxK
U2 - 10.1007/s10641-006-9022-7
DO - 10.1007/s10641-006-9022-7
M3 - Article
SN - 0378-1909
VL - 76
SP - 211
EP - 219
JO - Environmental Biology of Fishes
JF - Environmental Biology of Fishes
IS - 2-4
ER -