Human induced turbidity alters reproductive success and the stength of sexual selection in a pipefish
(English)Manuscript (preprint) (Other academic)
Human induced environmental change has the potential to alter species interactions, population dynamics and evolutionary processes. One such environmental change is algal induced turbidity, caused by eutrophication. While changes in mate choice and sexual selection due to turbidity has been demonstrated, the possible impact on mating systems remains to be explored. In this study we investigated the impact of algal turbidity on reproductive success, mating system and sexual selection using two populations of the broad-nosed pipefish, Syngnathus typhle, one from the Swedish west coast and one from the Baltic Sea. Under natural conditions, both populations practise a polygynandrous mating system with males as well as females having several partners. However, in a population from the Venice lagoon, where turbidity levels are high, the male mating system is shifted towards polyandry, with most males mating with one female only. In an experimental setting we tested whether this shift in mating system could be driven by turbidity alone. Contrary to our expectations, we found no effect of turbidity on the male mating system in terms of a general shift towards genetic polyandry. However, a positive relationship between male body length and number of mates was stronger in turbid environments for the Baltic Sea population. This indicates that although turbidity did not seem to affect the number of females a male mated with it has the potential to affect the strength of sexual selection. Further, for this population the turbid environment resulted in lower reproductive success.
Eutrophication, Mating system, Mate choice, Syngnathidae
Research subject Biology with specialization in Animal Ecology
IdentifiersURN: urn:nbn:se:uu:diva-195087OAI: oai:DiVA.org:uu-195087DiVA: diva2:608495