Climate change, thermal niches, extinction risk and maternal‐effect rescue of toad‐headed lizards, Phrynocephalus, in thermal extremes of the Arabian Peninsula to the Qinghai—Tibetan Plateau

Abstract

Determining the susceptibility of species to changing thermal niches is a major goal for biologists. In this paper we develop an eco-physiological model of extinction risk under climate change premised on behavioral thermoregulation. Our method downscales operative environmental temperatures, which restrict hours of activity of lizards, h , for present-day climate (1975) and future climate scenarios (2070). We apply our model using occurrence records of 20 Phrynocephalus lizards (or taxa in species complexes) drawn from literature and museum records. Our analysis is phylogenetically informed, because some clades may be more sensitive to rising temperatures. Computed h limits predict local extirpations among Phrynocephalus lizards at continental scales and delineate upper boundaries of thermal niches as defined by Extreme Value Distributions. Under the 8.5 Representative Concentration Pathway scenario, we predict extirpation of 64% of local populations by 2070 across 20 Phrynocephalus species, and 12 are at high risk of total extinction due to thermal limits being exceeded. In tandem with global strategies of lower CO emissions, we propose regional strategies for establishing new National Parks to protect extinction-prone taxa by preserving high-elevation climate refugia within existing sites of species occurrence. We propose that evolved acclimatization - maternal plasticity - may ameliorate risk, but is poorly studied. Previous studies revealed that adaptive maternal plasticity by thermoregulating gravid females alter progeny thermal preferences by ±1°C. We describe plasticity studies for extinction-prone species that could assess whether they might be buffered from climate warming - a self-rescue. We discuss an epigenetic framework for studying such maternal-effect evolution. This article is protected by copyright. All rights reserved.

A test of desert shrub facilitation via radiotelemetric monitoring of a diurnal lizard

“…Although facilitation as an ecological process does not necessarily include lifetime fitness as a component (Stachowicz, , Bruno et al, , Michalet et al, , Michalet & Pugnaire, ), our inference that E. californica facilitates G. sila would take on additional relevance, particularly to the potential for community structuring and the promotion of resilience in lizard populations, if the effects of E. californica facilitation on G. sila individual fitness were quantified. In the case of diurnal lizards, the link between thermal habitat quality and individual fitness has been firmly established by both theory and empirical testing (Kirchhof et al, , Ortega, Mencía, & Pérez‐Mellado, , Vickers et al, , Pontes‐da‐Silva et al, , Sinervo et al, , Camacho et al, ), but we believe further study on the E. californica — G. sila relationship with respect to individual fitness is warranted.…”

Climate suggests environment‐dependent selection on lizard colour morphs

“…intrasexual selection and fecundity selection) during range expansion. This has been attributed to geographical differences in thermal ecology (Friedman et al., ; Paranjpe, Bastiaans, Patten, Cooper, & Sinervo, ; Sinervo et al., ). In contrast, population morph frequencies of the Australian colour polymorphic tawny dragon, Ctenophorus decresii , appears to be driven by local aridity and vegetation cover, with no relationship between morph composition and the genetic divergence or geographical distance (McLean et al., ).…”

Biological buffers and the impacts of climate change

“…They find consistent among-individual variation, which is a prerequisite for selection. Sinervo et al (2018) also examine thermal preferences but address the question of whether plasticity of maternal thermal preference can alter progeny thermal preferences, and thereby help buffer climate warming by behaviorally reducing "hours of restriction" experienced by offspring. Sinervo et al (2018) invoke a novel, if complex, epigenetic and epistatic framework and outline its relevance to modeling impacts of climate warming.…”

“…Alternatively, plasticity can facilitate genetic adaptation by enabling persistence (Hendry 2016). Furthermore, plasticity can have longterm effects through trans-generational epigenetic inheritance and genetic assimilation (Pigliucci et al 2006;Sinervo et al 2018).…”