The African Clawed Frog (Xenopus laevis), is a primarily aquatic and highly- adaptable amphibian. They can inhabit almost any body of water, including a wide-range of salinities, temperatures, and tolerate a range of pollutants. Native to southern and sub-Saharan Africa, Xenopus currently has invasive populations in North America, Europe, and Asia. 

The hardiness and long-life span of Xenopus (15-30 years) has made it a widely used model for biomedical research. As such, there is a rich base of knowledge of the embryology and developmental physiology of this organism. While the morphological and physiological changes throughout their life have been well examined, little research has investigated the ecological behavior of these animals in light of their developmental physiology. Given the invasive nature of Xenopus, understanding the behavioral physiology of these animals could be valuable in our comprehension of its ecological impact. Like many anurans, Xenopus undergo dramatic morphological changes throughout their life via a full metamorphosis. Being an aquatic species, Xenopus requires water for all stages of their life cycle. Upon hatching, Xenopus have a tadpole form, which primarily obtains nutrients through filter feeding. The time to metamorphosis varies based on temperature and abundance of food, but typically occurs within a two month period. 

 Xenopus have multiple sensory systems that allow it to thoroughly navigate its environment. Like many aquatic organisms, they have a well-developed lateral line system that is used to detect wave stimuli created by prey and predators, and orient themselves in their environment. The eyes of Xenopus are located dorsally on the head, suggesting the importance of sight in detection of predators and prey in air and overhead, rather than through water. It appears that they can only see short distances, and frogs have only been observed catching prey close to the surface of the water.

Adult Xenopus have a widely variable diet that consists of insects, vertebrates, fish, amphibians, and plants. Cannibalism naturally occurs within this species, and they will eat tadpoles, Xenopus eggs and each other when food is scarce. Adult Xenopus show a consistent pattern of feeding behaviors that differs from other frogs because of their lack of an extensible tongue. Feeding behavior is characterized by forelimbs extended with their bodies oriented in the direction of the prey. If food is above the frog’s eyes, they will immediately orient towards the food, lunge and engulf the prey. Prey is captured via a sweeping action using the front feet and funneling the item into their mouth and gripping with their small-toothed jaws.

Interested in learning more about frogs and the challenges to conservation? See our video on disappearing frogs.

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