Phenotypic consequences of maternally selected nests: a cross‐fostering experiment in a desert lizard

Abstract

Despite the importance of maternally selected nests in shaping offspring phenotypes, our understanding of how the nest environment affects embryonic development and offspring traits of most non‐avian reptiles is rather limited largely due to the logistical difficulty in locating their nests. To identify the relative contributions of environmental (temporal [seasonal] and spatial [nest‐site]) and intrinsic (clutch) factors on embryonic development and offspring traits, we conducted a cross‐fostering experiment by swapping eggs between maternally‐selected nests of the toad‐headed agama (Phrynocephalus przewalskii) in the field. We found that nest environment explained a large proportion of variation in incubation duration, hatching success, and offspring size and growth. In contrast, clutch only explained a small proportion of variation in these embryonic and offspring traits. More significantly, compared with spatial effects, seasonal effects explained more phenotypic variation in both embryonic development and offspring traits. Eggs laid early in the nesting season had longer incubation durations and produced smaller hatchlings with higher post‐hatching growth rates than did later‐laid eggs. Consequently, hatchlings from early‐laid eggs reached larger body sizes prior to winter. In addition, we found that female toad‐headed agama did not select nests specific to reaction norms of their own offspring because hatchlings from original or translocated nests had similar phenotypic traits. Overall, our study demonstrates the importance of seasonal variation in nest environments in determining embryonic development and offspring phenotypes, which has not been widely appreciated at least in non‐avian reptiles.

How incubation temperature affects hatchling performance in reptiles: an integrative insight based on plasticity in metabolic enzyme

“…After collection, the fertilized eggs were weighed (±0.001 g) and incubated in a temperature-controlled incubator (KB240, Binder, Germany). We used a clutch-split design to incubate the eggs (e.g., Sun et al 2018a ; Li et al 2020a , 2020b ). In brief, three eggs from each clutch were evenly and randomly assigned to three different constant incubation temperatures in a temperature-controlled incubator (KB240, Binder, Germany) of 24 °C, 28 °C, and 32°C; these 3 temperatures represent the low, medium, and high temperatures experienced by the eggs in natural nests, respectively ( Figure 1 ).…”

“…Evaluating the effects of warming temperatures on animals thus plays an important role in understanding the threat imposed by climate warming ( Sinervo et al 2018 ). Phenotypic plasticity is one way that animals can respond to climate warming ( Williams et al 2008 ; Logan and Cox 2020 ; Li et al 2020a , 2020b). Therefore, determining the phenotypic plasticity to temperature variation is not only important to understand the effects of warming temperatures on animals, but also critical to predicting the vulnerabilities of animals to climate warming ( Huey et al 2012 ; Miller et al 2018 ; Sun et al 2022 ).…”

Geographical Variation in Body Size and the Bergmann’s Rule in Andrew’s Toad (Bufo andrewsi)

“…Environmental variations can impose pressures on an animal’s physiology [ 1 , 2 , 3 ], phenology [ 4 , 5 , 6 ], morphology [ 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ], distribution [ 20 ], and life-history strategies [ 21 , 22 , 23 , 24 , 25 , 26 ]. The ecogeographic patterns of covariation between biological traits and environmental variables [ 27 ] provide opportunities to assess the adaptions of animals in response to the selection pressures imposed by significant variations in temperature, precipitation, and associated microclimate variations [ 28 , 29 ].…”

Maternal egg care enhances hatching success and offspring quality in an oviparous skink

“…Email: duweiguo@ioz.ac.cn [Correction added on October 11, 2021 after first online publication: The missing symbol "±" has been inserted in Figure 1 and Figures 2 and 3 have been rotated 90 degrees counterclockwise.] via a variety of ways (e.g., investing more energy into offspring, providing favorable environmental conditions for embryonic or larval development, and helping juveniles develop their survival skills) (Clutton-Brock 1991;Uller 2008;Smiseth et al 2012;Burgess & Marshall 2014;Du et al 2014;Klug & Bonsall 2014;Li et al 2021). Parental care behavior is one of the most common forms of parental effort and occurs in various animal groups from arthropods to mammals (Queller 1997).…”

“…2014; Klug & Bonsall 2014; Li et al . 2021). Parental care behavior is one of the most common forms of parental effort and occurs in various animal groups from arthropods to mammals (Queller 1997).…”