TY - JOUR
T1 - Shift in investment between sexually selected traits
T2 - Tarnishing of the silver spoon
AU - Basolo, Alexandra L.
N1 - Funding Information:
I thank the Fisheries Ministry of Belize for awarding collecting permits, K. Kallman for sharing his expertise on Xiphophorus, J. Gardner, F. Pfertner and R. Traylor for their assistance with fish measurement, female choice tests and fish maintenance, J. E. Endler for his encouragement of this work and J. E. Endler, C. St Mary, K. Benson, B. Trainor, W.E. Wagner, Jr and R. Warner for comments on the manuscript. Support for this research was provided by an NSF Doctoral Dissertation Improvement Grant. Support was provided by NIMH-B/START grant MH55288 and NSF-RPG grant IBN9509211 during manuscript preparation.
PY - 1998/3
Y1 - 1998/3
N2 - Studies of resource allocation strategies have concentrated on the influence of natural selection on the evolution of life history traits. To a lesser degree, the effects of trade-offs between natural and sexual selection on the evolution of allocation strategies have also been considered. Trade-offs between sexually selected traits that are important to females but that appear to differ in cost, however, have not been considered. Female green swordtails, Xiphophorus helleri, prefer males with longer swords to males with shorter swords, and in this study they demonstrated a preference for larger males to smaller males. Furthermore, sexually mature males invested differentially in body and sword growth depending on resource availability; males that had an unlimited amount of food invested in both body and sword growth, but males shifted to a food-restricted regime halted investment in body growth and invested only in sword growth. These results suggest that males shift their pattern of investment in two sexually selected traits when food becomes restricted. In general, variable environmental conditions may favour such conditional investment strategies in species in which there is more than one preferred male trait and the costs of the traits differ.
AB - Studies of resource allocation strategies have concentrated on the influence of natural selection on the evolution of life history traits. To a lesser degree, the effects of trade-offs between natural and sexual selection on the evolution of allocation strategies have also been considered. Trade-offs between sexually selected traits that are important to females but that appear to differ in cost, however, have not been considered. Female green swordtails, Xiphophorus helleri, prefer males with longer swords to males with shorter swords, and in this study they demonstrated a preference for larger males to smaller males. Furthermore, sexually mature males invested differentially in body and sword growth depending on resource availability; males that had an unlimited amount of food invested in both body and sword growth, but males shifted to a food-restricted regime halted investment in body growth and invested only in sword growth. These results suggest that males shift their pattern of investment in two sexually selected traits when food becomes restricted. In general, variable environmental conditions may favour such conditional investment strategies in species in which there is more than one preferred male trait and the costs of the traits differ.
UR - http://www.scopus.com/inward/record.url?scp=0031923214&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0031923214&partnerID=8YFLogxK
U2 - 10.1006/anbe.1997.0634
DO - 10.1006/anbe.1997.0634
M3 - Article
C2 - 9515052
AN - SCOPUS:0031923214
SN - 0003-3472
VL - 55
SP - 665
EP - 671
JO - Animal Behaviour
JF - Animal Behaviour
IS - 3
ER -