Cichlid Fish as Research Models

Lake Malawi cichlids:

To engage individuals in modeling practices, we often use tropical cichlid fish in our studies:

Lake Malawi, the third largest lake in Africa, holds a monophyletic radiation of more than 450 cichlid species. This speciation has been primarily intralacustrine which is particularly remarkable given the fact that the lake is only approximately 2 million years old. A common opinion among researchers is that lake level fluctuations have contributed significantly to population isolation and micro-allopatric speciation. Population isolation and ultimately speciation has also, in many cases, been linked to sexual selection through female choice because variation in female preference can result in assortative mating. The mbuna (rock dwellers) are an extremely diverse group of brightly colored Lake Malawi cichlids that inhabit rocky outcroppings, to which they are endemic. In addition, all mbuna are maternal mouthbrooders and are associated with a lack of larval dispersal and high philopatry. Though mbuna are similar in morphology (trophic specializations excluded), they show vast color differences between species. It has been well established that though many mbuna exist in sympatry, there is little interbreeding in the field or in the lab. Sexual selection through female choice is believed to have facilitated mbuna speciation.

We are investigating:

  • Cues that females use to select mates both within and among species
  • Male dominance behavior
  • Variability in male mating success and within species female choice

  1. Rutgers
  2. New Brunswick
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