Mysteries of reptile reproduction

EGG-BORN?
This is true for turtles and crocodiles. However, in other reptiles, this is not always the case. Some snakes and lizards give birth to live young, which is particularly advantageous for species living in colder habitats, as the temperature in the mother’s body is more stable than inside eggs buried in the ground. Aquatic species, such as the anaconda, benefit from giving birth to live young because they do not have to come out of the water to lay eggs.

CARING PARENTS
Reptile parents may not feed their young—who can fend for themselves—but they are not oblivious: Crocodiles and cobras build nest piles, pythons coil around their eggs and shiver their bodies to keep them warm, many reptiles defend their eggs or young against nest robbers, and some help their offspring hatch. What’s more, parents often do not leave their nests even for food and may starve for months!

MALE OR FEMALE?
In iguanas, gender is determined by the father. If he passes an X chromosome onto his offspring, a female will be born, while a Y chromosome will result in a male. In lizards, monitors, and snakes, however, it’s upon mother, and in crocodiles, most turtles, and some agamas, gender depends on the incubation temperature. By adjusting it, zoo staff can influence which gender will be prevalent upon hatching.

REPTILE HATCHING IN PRAGUE ZOO
In our zoo, we mostly incubate reptile eggs in the off-exhibit areas of the Feline and Reptile House. There is a room equipped with several incubators we can set various combinations of humidity and temperature depending on what each egg needs for its development. Moreover, species that require their eggs to go through a cold period to start developing—such as the leopard tortoise—have their eggs chilled in a wine cooler!

RECORDS OF OUR INCUBATOR ROOM

CZECH: Mysteries of reptile reproduction