For animals to communicate effectively, signals are required to be successfully detected by an intended receiver across the extent of their distribution. However, changes in the structure of the landscape, or variation in environmental conditions poses interference to effective communication. Therefore, animals which successfully occupy different environments are expected to develop detectable signals in each of the environments. We explored the possibility of visual signal differentiation due to the influence of landscape structure. We explored variation in the visual signals of six species of Anolis lizards from Ecuador. Focussing on intra-specific variation, we tested the hypothesis of local adaptation as a driver of signal differentiation. The results present evidence for intra-specific differentiation due to the influence of forest type. This variation seems to reduce colour contrast and increase the motion effort at high elevations, suggesting that high mountain forests impose strong selective pressure for signalling differentiation. Interestingly, not all species responded similarly, indicating that other factors are involved.
(Note: featured image shows extended dewlap of A. proboscis – not involved in the current study)