Nile monitor

The Nile monitor, known scientifically as Varanus niloticus, is one of the largest lizards in the world.

It belongs to the monitor family, called Varanidae. These reptiles are found throughout most of Sub-Saharan Africa. They prefer living near rivers and tributaries, especially in East Africa. They thrive in many habitats, but they do not live in desert regions like the Sahara or the Kalahata. Because of their size and strength, they are very important members of their ecosystems. They are even larger than Australia's perentie lizard.

This lizard has several physical features that help it survive in different environments. It has a muscular body and strong legs for moving on land. Its nostrils are placed high on its snout. This placement helps the animal breathe while it is swimming.

They are also excellent climbers and quick runners. The Nile monitor uses sharp claws to climb trees, dig in the soil, or defend itself. To find food, it uses a forked tongue. This tongue has highly developed olfactory properties, which means it is very good at smelling.

The diet of a Nile monitor is very diverse. They are carnivores that eat many different types of prey. They consume fish, frogs, toads, and small reptiles like turtles and snakes. They even eat young crocodiles.

They also eat birds, rodents, and various invertebrates like beetles, crabs, and snails. Some monitors even eat carrion, which is dead animal matter. Their teeth change as they age to help with this diet. Juvenile monitors have sharp, pointed teeth. Adult teeth become blunt and peg-like.

Scientists have a long history of studying these monitors. The Djenné-Djenno culture in Africa likely caught them for food at least a millennium ago. In 1758, Carl Linnaeus first named the species Lacerta monitor. He later described it as Lacerta nilotica in 1766. This second name is the one that is considered valid today. In 1820, Blasius Merrem created the genus name Varanus. Later, in 1826, Leopold Fitzinger moved the monitor into this genus. This resulted in the name Varanus niloticus, which is the name used by scientists today.

There is also a complex history regarding how these lizards are classified. For a long time, scientists thought the Nile monitor was a single species. However, research has shown it is actually a species complex. This means it contains several groups that are very similar. In 1942, Robert Mertens grouped the ornate monitor and the West African Nile monitor together with the Nile monitor. Later, in 1997, a review suggested the ornate monitor was a separate species.

In 2016, genetic studies provided even more detail about these groups.

Genetic data revealed that the West African Nile monitor is a distinct species. This species, Varanus stellatus, lives in West African forests and savannahs. It is estimated to have split from the other monitors about 7.7 million years ago. This split happened even before humans and chimpanzees diverged. The monitors in Central African rainforests are genetically similar to the Nile monitor. This discovery changed how scientists view the ornate monitor. Because the type locality for the ornate monitor is in Cameroon, its name became a synonym for the Nile monitor.

In recent years, Nile monitors have become an invasive species in Florida, United States. They have established breeding populations there since at least 1990. Many of these lizards may have escaped from people keeping them as pets. During intense hurricane seasons, damaged enclosures may allow reptiles to escape into the wild.

This is a concern because they can negatively impact native animals. In Africa, they often raid crocodile nests and eat eggs. In Florida, they might do the same to American alligators and crocodiles. They are also known to be quite aggressive and difficult to keep in captivity.