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EVOLUTIONARY GENETICS

OF CICHLID FISHES

 
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Olfaction

Haplochromine cichlids exhibit maternal mouthbrooding, a type of parental care in which females pick up their eggs in their mouths and carry them until the yolk sac is absorbed (approximately 21 days post fertilization).  Male involvement is limited to fertilization; they provide no care to the offspring.

We are intrigued that the intimate association of developing fry with their mothers might provide opportunities for olfactory imprinting and later influence the mate preferences of adult females.  Verzijden and ten Cate (2007) raised broods of two different species of mouthbrooding cichlids from Lake Victoria in one of four rearing treatments: full brood with conspecific mother, full brood with heterospecific mother, mixed species brood with conspecific mother, and mixed brood with heterospecific mother. When the offspring reached maturity they measured the number of times females approached males of each species, and the number of displays they performed with each male.  They found that females approached more often, and performed more mating behaviors, with males of the same species as their foster mother.  Given the close proximity of maternal olfactory cues, it seems likely that olfactory imprinting at early developmental stages is affecting adult mate preference.  Many of these results have been replicated with a second pair of species (Verzijden et al. 2008).

This is an exciting result that demands further study. With our large fishroom and genomics expertise, we are well-positioned to study olfactory communication among Lake Malawi cichlids.

References

Plenderleith M, van Oosterhout C, Robinson RL, Turner GF. 2005. Female preference for conspecific males based on olfactory cues in a Lake Malawi cichlid fish. Biol Lett. 1:411-4.

Verzijden MN, ten Cate C. 2007. Early learning influences species assortative mating preferences in Lake Victoria cichlid fish. Biol Lett 3:134-136. 

Verzijden MN, Madeleine Korthof RE, ten Cate C. 2008.  Females learn from mothers and males learn from others.  The effect of mother and siblings on the development of female mate preferences and male aggression biases in Lake Victoria cichlids, genus Mbipia.  Behav Ecol Sociobiol 62:1359-1368.

 

 

 

 

 
 

 

Olfactory epithelium

Olfactory rosette

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Images by Justin Marshall