Red zebra cichlid shaking trial#

Using pedigree-based analyses, we show that stripes and body elongation segregate independently, indicating that the two traits are not genetically linked. Moreover, stripe patterns show strong signs of correlated evolution with body elongation, suggesting that the stripes' effectiveness as antipredatory strategy might differ depending on the body shape. A phylogenetic supertree of these species shows that stripe patterns evolved ~70 times independently and were lost again ~30 times. To study the evolutionary dynamics between color patterns and body morphology, we used an extensive dataset of 461 species. Cichlids are also well known for their diversity and repeated evolution of color patterns and body morphology. Species-rich adaptive radiations, such as the freshwater fish family Cichlidae, provide an exciting opportunity to study trait correlations at a macroevolutionary scale. Phylogenetic relationships between populations and species of rock-dwelling cichlids from Lake Malawi were reconstructed using both six microsatellite loci and AFLP markers.result has obvious implications for the time and cost required for large-scale studies of relatedness in natural populations.

However it was observed that nine loci provided a similar degree of accuracy to that obtained using eleven loci. It was found that using a higher number of more variable loci resulted in more accurate estimates of relatedness. A total of eleven loci were used in a combination of tests on known relatives and computer simulations. The effect on such estimates of locus number and heterozygosity was assessed in two species of cichlids from Lake Malawi ( M. Microsatellite DNA can also be used to generate statistical estimates of pairwise relatedness. However it was not clear if these results indicated genuine female choice or were a product of the design of the trials. In both cases, non-assortative mating was observed. nyererei ), and the other tested two allopatric populations of the same putative species from Lake Malawi ( Metriaclima zebra ).

Red zebra cichlid shaking trial#

One trial tested a sympatric species pair from Lake Victoria ( Pundamilia pundamilia and P. Microsatellite DNA was used to assess the paternity of offspring in two sets of mate choice trials where females chose between males that differ in colour pattern. Given the apparent importance of male colour patterns in mate choice, the specific status of allopatric populations that vary in male colour patterns is unclear. The sexual dichromatism and breeding behaviour exhibited by some groups of African cichlids have led many researchers to infer that sexual selection through female preference for male colour patterns may be one such mechanism. The rapid nature of the evolution of these species has provoked intense interest in the evolutionary mechanisms responsible for causing and maintaining divergence in this remarkable group of organisms. P>The cichlid fish of the African Great Lakes represent an astounding example of explosive speciation and adaptive radiation. Selection on male coloration, as proposed in a recent mathematical model. This may explain rapid speciation by sexual Where available, colour has gained dominance over other criteria.

Females may use male display rates, size, or both when colour This implies a hierarchy of choice criteria. Sexual selection by direct mate choice, involving the capacity for individual assessment of potential mates by the female.įemales of both species responded more frequently to blue males under monochromatic light. Hence, male coloration in haplochromine cichlids does underlie In interspecific mate choice, rather than other characters. That female preferences could be altered by manipulating the perceived colour pattern implies that the colour itself is used Neither male behaviour nor overall female response frequencies differed between light treatments. Females of both speciesĮxhibited species-assortative mate choice when colour differences were visible, but chose non-assortatively when colour differences We recorded the behavioral responses of females to males of both species in paired male trials under white lightĪnd under monochromatic light, under which the interspecific differences in coloration were masked. Males of one species are red, those of the otherĪre blue. The species differ primarily in male coloration. We studied the effect of male coloration on interspecific female mate choice in two closely related species of haplochromineĬichlids from Lake Victoria.