What is "viviparous lizard"

n. 1 (&lit viviparous lizard English) 2 # ''Zootoca vivipara'', known as the (vern common lizard pedia=1) in its relatively northerly Eurasian range.

The viviparous lizard or common lizard, Zootoca vivipara (formerly Lacerta vivipara), is a Eurasian lizard. It lives farther north than any other species of non-avian reptile, and most populations are viviparous (giving birth to live young), rather than laying eggs as most other lizards do. It is the only species in the monotypic genus Zootoca.

Zootoca vivipara can be seen in a variety of different colors. Female Zootoca vivipara undergo color polymorphism (biology) more commonly than males. A female lizard's display differs in ventral coloration, ranging from pale yellow to bright orange and a mixed coloration. There have been many hypothesis for the genetic cause of this polymorphic coloration. These hypothesis test for coloration due to thermoregulation, predator avoidance, and social cues, specifically sexual reproduction. Through an experiment conducted by Vercken et al., color polymorphism in viviparous lizard is caused by social cues, rather than the other hypotheses. More specifically, the ventral coloration that is seen in female lizards is associated with patterns of sexual reproduction and sex allocation.