Diallel genetic analysis of the elements of paradise fish's (Macropodus opercularis L.) behavior in familiar and novel situations.

Elements of the paradise fish's ethogram were recorded in 1 familiar and 3 different unfamiliar situations and the inheritance of these behavioral elements was investigated employing a five times replicated diallel cross between 3 inbred strains. A generalized Hayman Analysis of Variance and a Variance Covariance Analysis were performed to estimate genetic effects and parameters, such as, additive genetic variance, different sorts of dominance variance, reciprocal effects, direction and degree of dominance, ratio between the frequency of dominant and of recessive alleles, minimum number of effective factors and heritabilities, etc. Knowing the genetic architecture, we make inferences about the possible evolutionary past of the behavioral elements and explain why selection might favor certain types of paradise fish's behavior in particular circumstances. In several cases a possibility of "monogenic" inheritance emerged. We explain this finding and conclude that in a cross experiment where the inheritance of phenotypical units are investigated by employing only a few genetically different strains this result may be expected.