Increased temperature disrupts chemical communication in some species but not others: The importance of local adaptation and distribution

Abstract

Environmental conditions experienced by a species during its evolutionary history may shape the signals it uses for communication. Consequently, rapid environmental changes may lead to less effective signals, which interfere with communication between individuals, altering life history traits such as predator detection and mate searching. Increased temperature can reduce the efficacy of scent marks released by male lizards, but the extent to which this negative effect is related to specific biological traits and evolutionary histories across species and populations have not been explored. We experimentally tested how increased temperature affects the efficacy of chemical signals of high‐ and low‐altitude populations of three lizard species that differ in their ecological requirements and altitudinal distributions. We tested the behavioral chemosensory responses of males from each species and population to male scent marks that had been incubated at one of two temperatures (cold 16°C or hot 20°C). In high‐altitude populations of a mountain species (Iberolacerta monticola), the efficacy of chemical signals (i.e., latency time and number of tongue flicks) was lower after scent marks had been exposed to a hot temperature. The temperature that scent marks were incubated at did not affect the efficacy of chemical signals in a ubiquitous species (Podarcis muralis) or another mountain species (I. bonalli). Our results suggest that specific ecological traits arising through local adaptation to restricted distributions may be important in determining species vulnerability to climatic change.

Does geographical isolation influence group recognition and social preference in an invasive lizard?

“…Overall, our findings contrast previous work evidencing attraction at the population level. These studies demonstrated that individuals did have the capacity to recognize individuals as being either foreign or local (Labra, 2011;Macedonia et al, 2013;Scott et al, 2015;Lin et al, 2016;Pizzatto et al, 2016;Iglesias-Carrasco et al, 2017). Preference was typically for those that were local rather than foreign as it promoted greater levels of foraging efficiency, predator defence and/or reproductive success (Billingham et al, 2010;Pizzatto et al, 2016).…”

“…Similar ecological conditions across populations of L. delicata could have prevented divergence in this species' recognition system. Local adaptation has often been thought to arise through plasticity in phenotypic signals which respond to variation in selective regimes (Seddon, 2005;Iglesias-Carrasco et al, 2017). Changes within the signalling environment prompt shifts in phenotypic traits that are used as cues, such as morphological, behavioural or auditory cues, in order for efficient transmission and detection of signalling information.…”

“…Much evidence does suggest that animals are indeed capable of discriminating between members of these classes by utilizing highly evolved recognition systems (Ord & Stamps, 2009;Labra, 2011;Pizzatto et al, 2016;Iglesias-Carrasco et al, 2017) and that a selective response towards these class-specific signals provides a high fitness value (Goth, 2004;Mateo, 2004;Campbell & Hauber, 2009;Ord & Stamps, 2009). In having recognition systems that are inherent to each class, identification errors are less likely to occur, reducing the potential of agonism or wasted reproductive investment by way of nonviable or infertile hybrid offspring (Mateo, 2004;Ord & Stamps, 2009;Labra, 2011).…”

“…Of the relatively few studies investigating the discriminatory capacities and social preferences among different populations within species, they suggest that recognition systems for this class have evolved. Individuals were found to have the capacity of discriminating between foreign and local members (Rivault & Cloarec, 1998;Rupp & Woolhouse, 1999;Searcy et al, 2002;Wong, Keogh & Jennions, 2004;Labra, 2011;Lin et al, 2016;Iglesias-Carrasco et al, 2017). For instance, when exposed to a two-choice experiment involving playback of local and foreign echolocation stimuli, greater horseshoe bats (Rhinolophus ferrumequinum) responded more rapidly and spent a greater amount of time aggregating in local compartments (Lin et al, 2016).…”

Climate change as a catalyst of social evolution

“…The specificity, longevity, and 'honesty' of chemical signals makes them more versatile across social contexts than any other type of signal, including species recognition, neighbour/stranger discrimination, and kin recognition (Wyatt 2003). The nature of the specific signals used in olfactory communication and their efficacy have been shown to vary in response to climatic gradients across both micro-(e.g., Heathcote et al 2014, Sentis et al 2015 and macro-(e.g., Martín and López 2006, Baeckens et al 2018, Iglesias-Carrasco et al 2018 ecological scales. This is not surprising given that many components of chemical communication are heavily environmentally dependent.…”