In the 1940's-1950's there were no store bought pregnancy tests. A woman who suspected she was pregnant would go to a clinic and give a sample of her urine to the doctor. He would then inturn inject her urine into a female Xenopus laevis. If the female frog layed eggs the woman was pregnant, if not then the woman wasn't pregnant. When more modern methods came along the frogs were no longer needed so they were released into streams, ponds and small lakes in parts of California and other states. They have since established wild populations and have been destroying native frog species.

 

 

Xenopus laevis are mainly used in labratory research to study vertebrate embryology. They make a remarkable research animal due to the fact that the females are prolific egg layers. They embryos are also transparent so they are easy to observe in the developmental stages. They are also long lived, hardy and easy to care for in a labratory setting.

 

 

 

Some labs overseas are producing polydactyl Xenopus laevis. These frogs have an extra digit on their hands and feet. Leaving them with 6 toes and 5 fingers (instead of the normal 5 toes and 4 fingers). This is a genetic defect but does not affect the frogs health. Thanks to Melody for sharing this with me!

 

Freeze Branding Xenopus laevis was first used in 1976 as a way of indentifying an individual frog. This is an effective way of permanantly marking xenopus so they easily be told apart and reduce the amount of mixups in a labratory setting. This also could be used to identify and study wild populations of xenopus species, especially those who are declining. But for the most part this practice has been neglected by herpetologists.