Capturing and analyzing pattern diversity: an example using the melanistic spotted patterns of leopard geckos

Abstract

Animal color patterns are widely studied in ecology, evolution, and through mathematical modeling. Patterns may vary among distinct body parts such as the head, trunk or tail. As large amounts of photographic data is becoming more easily available, there is a growing need for general quantitative methods for capturing and analyzing the full complexity and details of pattern variation. Detailed information on variation in color pattern elements is necessary to understand how patterns are produced and established during development, and which evolutionary forces may constrain such a variation. Here, we develop an approach to capture and analyze variation in melanistic color pattern elements in leopard geckos. We use this data to study the variation among different body parts of leopard geckos and to draw inferences about their development. We compare patterns using 14 different indices such as the ratio of melanistic versus total area, the ellipticity of spots, and the size of spots and use these to define a composite distance between two patterns. Pattern presence/absence among the different body parts indicates a clear pathway of pattern establishment from the head to the back legs. Together with weak within-individual correlation between leg patterns and main body patterns, this suggests that pattern establishment in the head and tail may be independent from the rest of the body. We found that patterns vary greatest in size and density of the spots among body parts and individuals, but little in their average shapes. We also found a correlation between the melanistic patterns of the two front legs, as well as the two back legs, and also between the head, tail and trunk, especially for the density and size of the spots, but not their shape or inter-spot distance. Our data collection and analysis approach can be applied to other organisms to study variation in color patterns between body parts and to address questions on pattern formation and establishment in animals.

Thermal Tolerance Plasticity and Dynamics of Thermal Tolerance inEublepharis macularius: Implications for Future Climate-Driven Heat Stress

“…In this study, we established the critical thermal maximum (basal upper thermal tolerance), inferred the thermal tolerance plasticity and assessed their relationship in the gecko, Eublepharis macularius. E. macularius is becoming a model species for reptile studies in various fields of research (e.g., Hastings et al, 2023, Pinto et al, 2023, Katlein et al, 2022, Glimm et al, 2021, Kiskowski et al, 2021) and has well-documented molecular and genomic data compared to most other lizard species. E. macularius is typically active during dusk (Khan 2009; Gamble et al, 2015) and native to parts of northeast Iran and northwest India, where it inhabits deserts, shrublands, grasslands and rocky cliffs (Papenfuss et al, 2021).…”

The revised reference genome of the leopard gecko (Eublepharis macularius) provides insight into the considerations of genome phasing and assembly

“…Since its humble beginnings as a charismatic staple in the international pet trade, Eublepharis macularius has become a standard laboratory model system for studying a variety of biological questions surrounding tissue regeneration, coloration, sex determination, behavior, and cancer (Whimster, 1965; Viets et al, 1993; McLean & Vickaryous, 2011; Sakata et al, 2022; Delorme et al, 2012; Kiskowski et al, 2019; Szydłowski et al 2020; Glimm et al 2021; Guo et al 2021; Agarwal et al 2022; Katlein et al 2022). However, more detailed investigations into genotype-phenotype associations in E. macularius have been hampered by modest genomic resources (Chernyavskaya et al 2022; Gamble, 2019; Nurk et al 2022).…”

Reaction to Novel Objects and Fecal Glucocorticoid Metabolite Levels in Two Species of Nocturnal Geckos

“…These species are commonly kept and bred in captivity, making them valuable candidates for research. Consequently, they have been extensively used, especially leopard geckos, as a model species in studies of neurogenesis [30], epimorphic regeneration [31] or color pattern development [32]. Nevertheless, there are not many studies focused on welfare measures for them.…”