Science Assessment

Cichlids are a group of fish that live in freshwater lakes. Scientists wanted to determine whether two populations of cichlids that live at different depths of a lake interbreed. They knew that cichlids must be able to see potential mates in order to reproduce with them. They also knew that cichlids with particular genotypes see better at different water depths. Information about three different genotypes is summarized in the table below:

If scientists determined the genotypes of a representative sample of fish from both the deep and shallow water populations, what would provide the best evidence that some of the individuals in the deep and shallow water populations are reproducing with each other?

1. All individuals in both deep and shallow water populations have just the LL genotype.
2. Individuals with the LL, HH, and LH genotypes are present in both the deep and shallow water populations.
3. Only the LL genotype is present in the deep water population and only the HH genotype is present in the shallow water population.
4. Not enough information is provided.