Phenotypic consequences of incubation environment in the African elapid genus Aspidelaps

✍ Scribed by Steven B. Reichling; William H. N. Gutzke

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 753 KB
• Volume: 15
• Category: Article
• ISSN: 0733-3188
• DOI: 10.1002/(sici)1098-2361(1996)15:3<301::aid-zoo8>3.0.co;2-f

✦ Synopsis

Eggs and embryos of the African elapid genus Aspidelaps were tested for phenotypic plasticity in response to incubation temperature and hygration. Fifty-two fertile eggs, representing both A. lubricus and A. scutatus, were utilized over two successive breeding seasons. Interspecific difference in hatchling snout-vent length (SVL) was significant, but the two species were equivalent in initial egg mass and hatchling mass. Hatchling mass was unaffected by temperature and incubation substrate moisture, but was positively correlated to initial egg mass. In A. lubricus, SVL was influenced by an incubation temperature-substrate moisture interaction. In A. scutatus, SVL was unaffected by the experimental variables. The secondary sex ratio among hatchlings was significantly female skewed under mesic incubation conditions, and male skewed under xeric conditions. One explanation for the biased sex ratios is differential mortality at wet and dry conditions. The results indicate the two species of Aspidelaps are uniform with regard to female investment in egg and hatchling biomass, yet they partition resources differently during embryogenesis to yield morphologically distinct neonates.