In their last paper published in Journal of Evolutionary Biology, Guillem Pérez i de Lanuza and Enrique Font contemplate lizards colour patterns using a new approach. The authors hypothesize that selection for conspicuousness would not only act on the design of single colour patches, but also on the combination of adjacent colour patches. Indeed, lacertids lizard usually exhibit a long-wavelengths based ventral colouration (e.g. yellow or orange), while laterally they commonly display short-wavelengths colouration (e.g. UV, blue). To validate their hypothesis, they performed a comparative phylogenetic study. Their results clearly show that the contrast between these two color patterns is under selection.
These results highlight the complexity of the evolution of color patterns within a single animal and open new questions on this matter. Science will never cease to nourish our curiosity!