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Genetics/ Evolution for Sex-Limited Genes

You have found a sex-limited gene that codes for male color in a Lake Victoria cichlid fish species. The dominant (R) allele codes for a red color and the recessive (r) allele codes for a greenish color.

a) As you examine different populations of this species, you find that the R allele predominates in some populations and r allele predominated in others. Give two possible reasons for these difference.

b) Are the two reasons you have given mutually exclusive? That is, does one rule out the other?

c) What kind of selection would cause the female fish in the red-male and greenish-male populations to have behave differently?

d) Design an experiment to test whether there really are differences among females in their behavior towards the males in the two types of population.

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Genetics/ Evolution
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You have found a sex-limited gene that codes for male color in a Lake Victoria cichlid fish species. The dominant (R) allele codes for a red color and the recessive (r) allele codes for a greenish color.

a) As you examine different populations of this species, you find that the R allele predominates in some populations and r allele predominated in others. Give two possible reasons for these difference.

1. Selective forces acting on color traits and mate preferences for these traits in Lake Victoria cichlid fish.

The tremendous color variation among haplochromine cichlids plays an important role in both inter- and intraspecific mate choice, very little is known about the processes that drive (or constrain) the evolution of these color signals and color preferences in the first place. Sexual signaling may be subject to a variety of evolutionary pressures, exerting selection on both the senders and receivers of sexual signals. Insight in these selection pressures is required to assess the importance of haplochromine colors for the evolution of their extraordinary diversity.

2. If chances to mate between the individuals in a small population are random ...

Solution Summary

The expert examines genetics/evolution for sex-limited genes. Two reasons why you are given mutually exclusive events are determined.

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