Xenopus Background

 

Which Xenopus spp. (species) are used in biomedical research?

Two species of frog, X. laevis and X. tropicalis, are commonly utilized within biomedical research. Traditionally, X. laevis has been the “workhorse” for embryological studies, its fertilized eggs having been used to study vertebrate development for decades. Meanwhile, X. tropicalis has more recently emerged and could be argued as the more useful model. This smaller frog is the only member of Xenopus spp. with a diploid phenotype and has a much shorter lifespan, making it more amenable to genetics studies.

What about Xenopus in the wild?

Xenopus are a somewhat inactive animal and prefer the water, leaving only to migrate. Like other frogs, and unlike humans, these animals are cold-blooded, requiring mechanisms and/or behaviors to control body temperature. Because of this, Xenopus prefer mostly temperate environments. Also unlike humans, Xenopus undergo metamorphosis during development from the tadpole, which is entirely aquatic, into the adult frog, which can traverse terrestrial environments. In the wild, Xenopus adults are known to burrow into the ground during dry seasons, where they can remain dormant for up to one year.

Where can this frog be found?

Resident Xenopus populations are found primarily in Sub-Saharan Africa, where they are fairly common in ponds, lakes, and rivers. There also exist introduced, isolated populations of X. laevis in the Americas (mainly within the western U.S. and Chile) as well as in Europe (mainly France and the U. K.), where their ‘hardiness’ means they typically outcompete other resident frog populations.