Reproductive
Most reptiles reproduce sexually. All male reptiles except turtles and tortoises have a twin tube-like sexual organ called the hemipenes. Turtles and tortoises have a single penis. All testudines lay eggs, none are live bearing as some lizards and snakes are. All reproductive activity occurs with the cloaca, the single exit/entrance at the base of the tail where waste and reproduction happens.
Asexual reproduction has been identified in squamates in six families of lizards and one snake. In some species of squamates, a population of females are able to produce a unisexual diploid clone of the mother. This asexual reproduction called parthenogenesis occurs in several species of gecko, and is particularly widespread in the teiids (especially Aspidocelis) and lacertids (Lacerta) In captivity Komodo dragons (varanidae) have reproduced by parthenogenesis.
Parthenogenetic species are also suspected to occur among chameleons, agamids, xantusiids, and typhlopids.
Amniotic eggs are covered with leathery or calcareous shells. An amnion, chorion and allantois are present during embryonic life. There are no larval stages of development.
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