Real-Time Communication with WebRTC

Colophon

The animal on the cover of Real-Time Communication with WebRTC is the viviparous lizard (Zootoca vivipara), also known as the common lizard and scaly lizard. It is found throughout most of Europe and Asia, in one of the widest ranges of any vertebrate. Viviparous is a term applied to animals who birth live offspring, and indeed, these lizards have the ability to carry and deliver fully formed young. Interestingly, this seems to be an adaptation made solely for cool climates, as populations of this species in warmer areas like Spain and Italy lay eggs instead.

While the southern and northern populations of viviparous lizards also prefer slightly different types of habitat (for instance, the southern lizards can be found at higher elevations and in damper environments), they all live on the ground and spend their time eating small insects and basking in the sun to maintain body temperature. Northern lizards also hibernate from September to mid-February, while their southern cousins are active all year.

The viviparous lizard averages 13-15 centimeters long. Males have larger heads, more slender bodies, and colored underbellies, while females are much duller in color. As a species, however, their coloration varies a great deal. Most often, the lizards are brown with darker markings on their back and legs, but can also be green, gray, black, or red—which can make it difficult to identify them. It is quite likely that viviparous lizards should be reclassified into multiple subspecies, ...