![]() Il est maintenant admis que plusieurs canaux de communication sont impliqués dans les interactions sociales. Future speciation models aimed at explaining African cichlid radiations may therefore consider incorporating such mating cues in mate choice scenarios. We suggest that non-visual cues, such as olfactory signals, may play an important role in mate choice and behavioural isolation in these and perhaps other African cichlid fish. By contrast, assortative mating broke down when direct contact between female and male was prevented. emmiltos observed under control conditions. Conducting trials under monochromatic (orange) light, intended to mask the distinctive male dorsal fin hues (blue v orange) of these populations, did not significantly affect the assortative mating by female P. This suggested that assortative mating could be based on non-visual cues, so we further examined the sensory basis of assortative mating between two populations with different male colour. Surprisingly, laboratory mate choice experiments revealed significant assortative mating not only between population pairs with differently coloured males, but between population pairs with similarly-coloured males too. Fisher's exact tests as well as Binomial and Wilcoxon tests were used to detect if mating departed from random expectations. We used microsatellite genotypes or mesh false-floors to assign paternity. distantly-related populations that independently evolved similar colours would interbreed freely while more closely-related populations with different colours mate assortatively. We studied four populations of the Lake Malawi Pseudotropheus zebra complex. Here, we tested predictions from the hypothesis that allopatric divergence in male colour is associated with corresponding divergence in preference. Research on the evolution of reproductive isolation in African cichlid fishes has largely focussed on the role of male colours and female mate choice. Cuckoo catfish and mouthbrooding cichlids provide a model system for testing brood parasitism in a laboratory setting. Parasitism rates and number of catfish per brood were the highest in the albino morphotype suggesting that the higher levels of parasitism may be related to lower aggressive behavior, lower visual acuity, or captive influence. We also analyzed the parasitism rate of the albino morph of Metriaclima zebra, a domestic strain. horei parasitism frequency and number of cuckoo catfish per brood. Our results are comparable to findings from the field for C. The number of catfish eggs per parasitized brood was similar between C. horei may be due to differences in the mating ritual, oviposition (e.g., long periods of pseudo-spawning before actual oviposition), and behavioral adaptations (e.g., increased aggression towards the cuckoo catfish). ![]() horei was parasitized significantly less (17%) than the allopatric species Haplochromis latifasciatus, Haplochromis nubilus, and Metriaclima estherae (combined parasitism rate of 28%). Here we examine the frequency of parasitism by the cuckoo catfish of Ctenochromis horei from Lake Tanganyika and three species from Lake Malawi and the greater Lake Victorian system in a laboratory setting. The cuckoo catfish parasitizes Tanganyikan mouthbrooding cichlids, and under captive conditions, will also parasitize cichlids from other Rift Valley lakes. The only known non-avian vertebrate obligate brood parasite is the cuckoo catfish (Synodontis multipunctatus), a Lake Tanganyikan endemic.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |