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Reptile Reproduction - Anatomy & Physiology (view source)
Revision as of 08:08, 22 July 2008
, 08:08, 22 July 2008→Introduction
= Introduction =
= Introduction =
The evolutionary development of reptiles depended primarily on them being able to discard the attachment to a watery or humid environment for survival and breeding perposes. Of the numerous features exibited by reptilia as a group, the most important in an evolutionary context are:
* Almost all reptiles are covered by a protective layer of dry skin with almost no glands. The epidermis is raised to form scales or scutes. This prevents excessive water loss, thus is essential for terrestrial existence.
* They developed a large, yolked egg, allowing the embryo sufficient food reserves to develop fully before hatching. The yolked egg is surrounded by protective extra-embryonic membranes (the amnion and allantois), serving for respiration and the storage of waste. There is also a protective calciferous shell to prevent it from drying out.
= Temperature Dependent Sex Determination (TDSD) =
= Temperature Dependent Sex Determination (TDSD) =