Why Do Males ofParnassius imperatorFight for Bare Rocks but Not the Nectar Flower During Mate Selection?

Autor: Bo Du, Xin-Wei Da, Qing-Miao Ren, Rui Zhang, Guo-Liang Chen, Yi-Fan Lin
Rok vydání: 2016
Předmět:
Zdroj: Ethology. 122:552-560
ISSN: 0179-1613
DOI: 10.1111/eth.12502
Popis: Territoriality is an important male behavioral trait used in mate selection of butterflies, but the factors determining the outcome of territorial contests remain controversial. We studied the foraging and territorial behaviors of males in the Parnassius imperator butterfly. Adult males were selective about nectar sources, but they did not defend nectar flowers. By contrast, they fought over areas of bare rocks because bare rocks were used as lek locations to attract and court receptive females. The ownership of a lek, rather than sex pheromones or wing pigments, played the key role in attracting females. In an owner replacement experiment, the owner of a territory always defeated intruders, indicating that perching order, not relative body size, determined the outcome of territorial contests. Territories are small areas of bare rocks that lack food resources, so intruders do not challenge the ownership of a resident in a location where they can easily find vacant territories. Males that first perch in a territory have an advantage compared to intruders in that they can forage on flowers in the vicinity of the territory. This may help explain why satiated owners always defeated fatigued intruders. Our findings suggest that early perching on bare rock allows male butterflies of P. imperator to occupy a territory, attract receptive females and exclude later-arriving competitors.
Databáze: OpenAIRE