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  2. Temperature-dependent sex determination - Wikipedia

    en.wikipedia.org/wiki/Temperature-dependent_sex...

    Some reptiles use incubation temperatures to determine sex. In some species, this follows the pattern that eggs in extremely high or low temperatures become female and eggs in medium temperatures become male. [14] Within the mechanism, two distinct patterns have been discovered and named Pattern I and Pattern II.

  3. Parthenogenesis - Wikipedia

    en.wikipedia.org/wiki/Parthenogenesis

    A female produces an ovum with a full set (two sets of genes) provided solely by the mother. Thus, a male is not needed to provide sperm to fertilize the egg. This form of asexual reproduction is thought in some cases to be a serious threat to biodiversity for the subsequent lack of gene variation and potentially decreased fitness of the offspring.

  4. Parthenogenesis in squamates - Wikipedia

    en.wikipedia.org/wiki/Parthenogenesis_in_squamates

    Parthenogenesis is a mode of asexual reproduction in which offspring are produced by females without the genetic contribution of a male. Among all the sexual vertebrates, the only examples of true parthenogenesis, in which all-female populations reproduce without the involvement of males, are found in squamate reptiles (snakes and lizards). [1]

  5. Hemipenis - Wikipedia

    en.wikipedia.org/wiki/Hemipenis

    The hemipenis is the intromittent organ of Squamata, [4] which is the second largest order of vertebrates with over 9,000 species distributed around the world. They differ from the intromittent organs of most other amniotes such as mammals, archosaurs and turtles that have a single genital tubercle, as squamates have the paired genitalia remaining separate. [5]

  6. Reptile - Wikipedia

    en.wikipedia.org/wiki/Reptile

    Tuatara, however, lack copulatory organs, and so the male and female simply press their cloacas together as the male discharges sperm. [120] Most reptiles lay amniotic eggs covered with leathery or calcareous shells. An amnion (5), chorion (6), and allantois (8) are present during embryonic life. The eggshell (1) protects the crocodile embryo ...

  7. American alligator - Wikipedia

    en.wikipedia.org/wiki/American_alligator

    Male American alligators use infrasound to attract females. Eggs are laid in a nest of vegetation, sticks, leaves, and mud in a sheltered spot in or near the water. Young are born with yellow bands around their bodies and are protected by their mother for up to one year. [12] This species displays parental care, which is rare for most reptiles.

  8. Tuatara - Wikipedia

    en.wikipedia.org/wiki/Tuatara

    Tuatara have temperature-dependent sex determination meaning that the temperature of the egg determines the sex of the animal. For tuatara, lower egg incubation temperatures lead to females while higher temperatures lead to males. Since global temperatures are increasing, climate change may be skewing the male to female ratio of tuatara.

  9. Egg - Wikipedia

    en.wikipedia.org/wiki/Egg

    Reptile eggs, bird eggs, and monotreme eggs are laid out of water and are surrounded by a protective shell, either flexible or inflexible. Eggs laid on land or in nests are usually kept within a warm and favorable temperature range while the embryo grows. When the embryo is adequately developed it hatches, i.e., breaks out of the egg's shell.