African clawed frog

The African clawed frog (Xenopus laevis), also known as simply xenopus, African clawed toad, African claw-toed frog or the platanna) is a species of African aquatic frog of the family Pipidae. Its name is derived from the short black claws on its feet. The word Xenopus means 'strange foot' and laevis means 'smooth'.

The species is found throughout much of Sub-Saharan Africa (Nigeria and Sudan to South Africa), and in isolated, introduced populations in North America, South America, Europe, and Asia. All species of the family Pipidae are tongueless, toothless and completely aquatic. They use their hands to move food into their mouths and a special pump to help them swallow. These frogs have strong legs for swimming and catching food, and they use the claws on their feet to tear larger pieces of food.

It is considered an invasive species in several countries, including across Europe. This means that in places where they are not naturally found, these frogs can sometimes cause problems for local plants and animals.

Description

African clawed frogs are common in ponds and rivers in the south-eastern part of Sub-Saharan Africa. These frogs live in water and are usually a mix of green, gray, and brown, with a lighter, creamy white belly. They are often kept as pets and are sometimes confused with African dwarf frogs. Special white versions of these frogs, called albino frogs, are often used in science labs (animals for laboratories).

These frogs can live for many years—more than 15 years in the wild and up to 30 years when kept by people. They change their skin each season and even eat the old skin. Male and female frogs look different; males are smaller and thinner, while females are larger and rounder. Males have special black patches on their hands that help them hold onto females when they are ready to make babies.

Behaviour

African clawed frogs live in water and rarely leave it, except when moving to new water during dry times. They have strong legs for moving in water and on land, and special black claws on their feet to help them grab food and defend against other animals. These frogs eat many things, such as fish, small creatures, and even other frogs, using their hands to catch food since they do not have a tongue like some other frogs.

These frogs are active mostly at night and like to eat after dark. They can sense food in the water using special senses, but they also use their eyes to watch for food and possible threats. When they are not eating, they often sit still at the water's surface, keeping their eyes and nose above the water.

Biology

The African clawed frog has special ways to stay healthy, especially when it's cold. When the water gets chilly, its liver makes more of a certain substance that tells the thyroid gland to produce more heat. This helps the frog keep its body warm.

Scientists have also studied the fats inside the frog's cells and how the frog's genes change as it gets older. These studies show that some of the ways frogs age are similar to how mammals, like humans, age. This helps us understand more about how living things stay healthy over time.

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In the wild

The African clawed frog lives in wetlands, ponds, and lakes across dry and semi-dry areas of Sub-Saharan Africa. These frogs are well-known to local people, who sometimes eat them or use them in traditional practices.

In the wild, these frogs are often found in man-made water areas like ponds and dams. They can move over land to new water places, which sometimes causes problems for local plants and animals. These frogs can also carry tiny harmful creatures called parasites.

Use in research

The African clawed frog, Xenopus laevis, is very important for scientific studies. Its embryos and eggs are used a lot because they can lay eggs all year round. Scientists like to study these frogs because they are easy to work with and are closely related to humans, unlike many other lab animals.

These frogs were once used to tell if a woman was pregnant by putting her urine in their water. Today, scientists use special chemicals to make the frogs breed in labs anytime they want. They are also used to study how cells work, how embryos develop, and many other biological processes. One famous experiment using these frogs helped scientists understand how vision develops.

Online Model Organism Database

Xenbase is the special website for learning about two types of frogs called Xenopus laevis and Xenopus tropicalis. This website shares important information, including details about the genes of Xenopus laevis that were fully mapped in 2022.

As pets

African clawed frogs have been popular pets and research subjects since the 1950s. They are very tough and can live for up to 20 or even 30 years when cared for properly.

Sometimes, these frogs are sold in pet stores and called African dwarf frogs, which can be confusing. There are a few ways to tell them apart: dwarf frogs have four webbed feet, while African clawed frogs have webbed back feet and front feet with separate toes. Dwarf frogs have eyes on the sides of their heads, but African clawed frogs have eyes on the tops of their heads. Also, African clawed frogs have curved, flat snouts, while dwarf frogs have pointed snouts.

Main article: African dwarf frogs

As pests

The African clawed frog is a strong eater and can live in many different places, which sometimes causes problems. These frogs can travel short distances and even survive cold weather, allowing them to spread to new areas. They have hurt some local frog groups by eating their young.

In 2003, these frogs were found in a pond in San Francisco at Golden Gate Park. People are working hard to stop them from spreading further. It is not clear how they got there, but officials took steps to keep them contained. Owning these frogs without special permission is not allowed in many places in the United States, including Arizona, California, Kentucky, Louisiana, New Jersey, North Carolina, Oregon, Vermont, Virginia, Hawaii, Nevada, and Washington state. However, they can be kept in places like New Brunswick in Canada and Ohio.

There are also groups of these frogs living wild in South Wales and the United Kingdom. In Yunnan, China, a special group of pale frogs lives in Lake Kunming, along with another frog from America.

These frogs might help spread a harmful sickness among other frogs, even though they do not get sick themselves. This sickness has caused big drops in the numbers of frogs around the world. Because of this, many are working to control their numbers to protect local wildlife.