Geckos, a diverse group of lizards, primarily reproduce by laying eggs. This strategy, known as oviparity, is common among most of 2,000+ species across various climates. While most geckos are egg-layers, a few species give birth to live young. This highlights the reproductive diversity within the gecko family.
The Nature of Gecko Eggs
Gecko eggs vary by species, primarily categorized by shell type: hard-shelled or soft-shelled. Hard-shelled eggs, like those of the leopard gecko, have a rigid, calcified outer layer. This firm shell protects the developing embryo. These eggs typically maintain a consistent shape throughout incubation.
In contrast, many gecko species, such as crested geckos, lay soft-shelled or leathery eggs. These eggs have a pliable, parchment-like texture that allows for expansion as the embryo grows. They are generally white or off-white and can be slightly sticky when first laid. Their shell’s composition and flexibility are adaptations to the varying environmental conditions where geckos deposit their eggs.
The Egg-Laying Process and Environment
Female geckos carefully select hidden, protected sites for their eggs to ensure proper development. These locations include rock crevices, under loose tree bark, or buried in substrate like leaf litter or soil. Some species, like the Mediterranean house gecko, may even glue their eggs to surfaces for security.
Most gecko species lay a small clutch, typically one or two eggs. While some reproduce once a year, others, like the leopard or tokay gecko, can produce multiple clutches annually, sometimes four to six times. Laying frequency varies among species, with some laying clutches every 21 to 28 days during their breeding season. After laying, most geckos provide no parental care, allowing eggs to incubate and hatch independently.
From Egg to Hatchling
A gecko’s development inside its egg is influenced by external environmental factors. The incubation period, or time to hatch, typically ranges from 30 to 80 days, depending on the gecko species. Temperature and humidity are factors that affect incubation duration and can also influence the sex of developing geckos in species with temperature-dependent sex determination.
As the hatchling prepares to emerge, it develops an egg tooth, a small, sharp projection on its snout. The gecko uses this tooth to cut or break through the eggshell. Once hatched, young geckos are miniature versions of adults and are immediately independent, possessing the necessary instincts for survival.