Fitness disadvantages to disrupted embryogenesis impose selection against suboptimal nest-site choice by female grass snakes, Natrix natrix (Colubridae).

摘要: Phenotypic traits of hatchling reptiles are strongly influenced by incubation regimes (e.g. temperature and moisture), suggesting that maternal choice suitable nest-sites should be under intense selection. Our laboratory 209 eggs (17 clutches) from wild-caught Swedish grass snakes (Natrix natrix) showed scale abnormalities (half-scales on one side the body, often reflecting lateral asymmetry in number ribs) occurred more frequently if were incubated cooler conditions. Especially at low temperatures, individuals with asymmetries took longer to hatch than did symmetric conspecifics, smaller body length hatching slower trials locomotor speed. Anti-predator tactics also covaried asymmetry. These patterns suggest asymmetric scales have lower fitness hence rarely survive adulthood wild. We tested this prediction examining 201 field-collected museum collections. As predicted, seen primarily small snakes, larger animals. interpret these data species offer an index developmental instability disadvantages disrupted embryogenesis impose selection against suboptimal nest-site females.