Each block contained 5 images of one bird type at a certain morph level.
In addition, although there is suggestive evidence that male preference for a certain female morph depends on the previous experience with that female morph e.g. [ 27], the role of innate male mating preferences and ontogenetic changes in male preference have until now received little attention [ 28].
The overall high neutral FST-value for this lizard species (0.208) should, however, increase our statistical power to detect stabilizing selection in this system that might have favored a certain stable morph frequency equilibrium in all populations.
An obvious suggestion is that divergent selection or gene-by-environment interactions [ 45] affect the precise equilibrium, favouring certain morphs under a given set of ecological conditions such as particular densities of con- and heterospecific damselflies, differences in climate, predation rate or parasite load among populations.
My lapse into unhealthy eating was slow and insidious, beginning as a reasonable desire to eat healthier, but sneakily morphing into intense feelings of guilt for eating a certain way, or eventually, for eating anything at all.
A certain flavour or texture?
On the boundary between each phase, disadvantage in the fitness potential of certain morphs is countered by rare morph advantage when its frequency is juts zero.
Even when potential fitness in a given population differs between morphs, polymorphism is protected in the population if the advantage of fitness potential of certain morphs is countered by frequency-dependent disadvantage (common morph disadvantage).
Given that discrete colour morphs are often genetically correlated with other traits such as behaviour, physiology and life-history, selection may act on these correlated traits which make certain morphs better adapted to different environments.
Furthermore, transitions towards heteroecy necessitate changes in the ability to produce certain morphs (heteroecious species must necessarily produce winged males, while some of the monoecious Brachycaudus produced unwinged males only [ 14]) as well as changes in host preference for Prunus in several morphs (winged males and gynoparae).
Obsessed with a certain snack or drink?
