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Green iguana

life science Maturity 11-13

The green iguana is a big lizard.

FL Iguana.jpg
FL Iguana.jpg
It lives in trees. It eats plants and leaves. It has spikes on its back. These spikes help keep it safe. It can also swim well.
Green iguana (Iguana iguana) juvenile.jpg
Green iguana (Iguana iguana) juvenile.jpg
Do you like lizards?

44 words

The green iguana is a big lizard.

FL Iguana.jpg
FL Iguana.jpg
It lives in trees. It eats plants and leaves. It has spikes on its back. These spikes help keep it safe.
Green Iguana skull (Iguana iguana) and teeth.png
Green Iguana skull (Iguana iguana) and teeth.png
It has very sharp teeth. These teeth help it shred leaves. The lizard can also swim. It uses its tail to move in water.
Green iguana (Iguana iguana) juvenile.jpg
Green iguana (Iguana iguana) juvenile.jpg
It can even fall from trees and land safely. This lizard is a very cool animal.

82 words

The green iguana is a large lizard.

FL Iguana.jpg
FL Iguana.jpg
It lives in trees. Most iguanas eat only plants. This diet means they must eat a lot of food. They have a special way to stay healthy. They use a salt gland to get rid of extra salt.
Green Iguana skull (Iguana iguana) and teeth.png
Green Iguana skull (Iguana iguana) and teeth.png
Their teeth are broad and flat. These teeth help them shred leaves. Some iguanas even have small horns on their noses.
Green Iguana, Solidaridad, Q.R., México imported from iNaturalist photo 33850312.jpg
Green Iguana, Solidaridad, Q.R., México imported from iNaturalist photo 33850312.jpg
These iguanas live from Mexico to Brazil. They can also be found on many islands. They are very good at climbing. They can even fall from trees and land without getting hurt.
Green iguana (Iguana iguana) juvenile.jpg
Green iguana (Iguana iguana) juvenile.jpg
Young iguanas are often bright blue. They stay in family groups for one year. Male iguanas may use their bodies to protect females. This is very rare for a reptile. Females lay between 20 and 71 eggs each year.

161 words

The green iguana is a very large lizard.

FL Iguana.jpg
FL Iguana.jpg
It is likely the biggest member of the iguana family. These animals are mostly herbivores, which means they eat plants. Because plants have less nutrition than meat, iguanas must eat a lot of food. They live in trees and are very good at climbing.
Green iguana (Iguana iguana) juvenile.jpg
Green iguana (Iguana iguana) juvenile.jpg
They can even fall from high branches and land without getting hurt. They use their claws to grab leaves to break their fall. They are also strong swimmers that use their tails to move through water.

Living on a plant diet creates a hard job for their bodies. Plants contain a lot of potassium. Most animals turn extra salt and minerals into liquid urine to stay healthy. However, iguanas cannot make urine that is more concentrated than their body fluids. To fix this, they use a special salt gland in their nose. This gland helps them get rid of extra salt and potassium.

Green Iguana skull (Iguana iguana) and teeth.png
Green Iguana skull (Iguana iguana) and teeth.png
They also have very sharp, leaf-shaped teeth to shred leaves. These teeth are so unique that a famous dinosaur was named after them.

Scientists have studied these lizards for a long time. Carl Linnaeus, a Swedish botanist, first described the species in 1758.

Iguana skeleton.jpg
Iguana skeleton.jpg
Researchers from Mexico, El Salvador, and the United States have studied them recently. They looked at DNA from animals in 17 different countries. This work helped them learn that iguanas likely started in South America. From there, they moved through Central America and the Caribbean. Scientists still debate if some groups are different species or just regional variants.

Green iguanas live in many places.

Iguanidae head from Venezuela.jpg
Iguanidae head from Venezuela.jpg
Their native home goes from Mexico to Brazil, Paraguay, and Bolivia. They also live on many Caribbean islands like Aruba and Grenada. Some iguanas have even moved to new places like Florida and Hawaii. These animals come in many colors depending on where they live. In Peru, they can look bluish with bold markings. In Costa Rica, some are bright red, while those in Mexico look orange.
Red head iguana from Costa Rica 2.jpg
Red head iguana from Costa Rica 2.jpg

Many things about an iguana's body help it survive. They have a row of spines on their backs for protection.

Poros inguinales Iguana.JPG
Poros inguinales Iguana.JPG
They also have a dewlap, which is a flap of skin under the chin. This helps them stay at the right temperature and show off to others. On top of their heads, they have a "third eye" called a parietal eye. It cannot see pictures, but it can feel light and dark. This helps them spot predators moving above them.
Green Iguana, Solidaridad, Q.R., México imported from iNaturalist photo 33850312.jpg
Green Iguana, Solidaridad, Q.R., México imported from iNaturalist photo 33850312.jpg
Even the young iguanas have special ways to stay safe in family groups.

462 words

The green iguana (Iguana iguana) is a large, arboreal lizard.

FL Iguana.jpg
FL Iguana.jpg
This means they spend much of their lives in trees. They are mostly herbivorous, meaning their diet consists mainly of plants. They are likely the largest species within the iguana family. While some other lizards might match them in weight, the green iguana is a massive reptile. They are native to a wide area from southern Mexico to central Brazil, Paraguay, and Bolivia.
Iguanidae head from Venezuela.jpg
Iguanidae head from Venezuela.jpg
They are also found throughout the Caribbean in places like Aruba and Grenada. Because they are so hardy, they have become highly invasive in many tropical environments around the world.

Living on a plant-based diet requires special biological adaptations. Plants have less dense nutritional content than meat. They also contain high levels of potassium. Because of this, iguanas must eat large amounts of food to meet their metabolic needs. This diet creates a challenge for osmoregulation, which is how an animal manages its internal salt and water balance. Most animals create concentrated liquid urine to remove excess salt. However, iguanas cannot make urine more concentrated than their own bodily fluids. To solve this, they use a lateral nasal gland. This salt gland helps them expel excess potassium and sodium chlorides.

Green Iguana skull (Iguana iguana) and teeth.png
Green Iguana skull (Iguana iguana) and teeth.png

An iguana's physical features help it survive in its environment. They have a row of spines along their backs and tails for protection.

Iguana skeleton.jpg
Iguana skeleton.jpg
Their tails are whip-like and can deliver painful strikes. If a predator grabs an iguana by the tail, the lizard can actually allow the tail to break off to escape. It will eventually regenerate a new one. They also possess a large dewlap under the chin. This flap of skin helps regulate body temperature and is used in territorial displays.
Poros inguinales Iguana.JPG
Poros inguinales Iguana.JPG
For vision, they have excellent color sight. They even possess a parietal eye on top of their heads. This "third eye" is a photosensory organ that detects changes in light and dark. It helps them spot predators moving above them.

Green iguanas show significant geographic variation in appearance. Despite their name, they are not always green. In Peru, they may appear bluish with bold markings. In Costa Rica, some are bright red.

Red head iguana from Costa Rica 2.jpg
Red head iguana from Costa Rica 2.jpg
In Mexico, they often appear orange. On various islands, they can be lavender, black, or reddish brown. Even within a single island, populations can differ. For example, iguanas on St. Lucia have black dewlaps and white irises. This is different from the typical orange dewlap and yellow irises seen in other populations. These differences show how the species adapts to specific local environments.

Scientific study of the species began in 1758. Swedish botanist Carl Linnaeus was the first to officially describe it.

Green Iguana, Solidaridad, Q.R., México imported from iNaturalist photo 33850312.jpg
Green Iguana, Solidaridad, Q.R., México imported from iNaturalist photo 33850312.jpg
Since then, the taxonomy, or the way we classify them, has changed frequently. Scientists from El Salvador, Mexico, and the United States used DNA-sequence data to study populations from 17 countries. This research suggested the species originated in South America. It then radiated through Central America and the Caribbean. There is still debate about certain groups. Some scientists believe certain populations are distinct species, while others classify them as regional subspecies.

Reproduction in green iguanas involves specific social and biological behaviors. They are oviparous, which means the females lay eggs. A female may lay a clutch of 20 to 71 eggs once per year.

Green iguana (Iguana iguana) juvenile.jpg
Green iguana (Iguana iguana) juvenile.jpg
After laying the eggs, the female provides no parental protection. The eggs hatch after an incubation period of 10 to 15 weeks. Interestingly, juvenile iguanas stay in familial groups during their first year. In these groups, males have been observed using their bodies to shield females from predators. This is the only reptile species known to exhibit this specific protective behavior.

Green iguanas are highly capable in different habitats. They are agile climbers that can fall from high branches without injury. They use their hind leg claws to grasp leaves and break their fall. When swimming, they stay submerged and use powerful tail strokes to move.

Indignity - Flickr - Carine06.jpg
Indignity - Flickr - Carine06.jpg
They are also skilled burrowers. They can create burrows that are quite deep with a diameter of 10 centimeters. Their presence in new areas, such as the island of Anguilla in 1995, provides evidence of oceanic dispersal. This happens when animals are washed ashore by events like hurricanes, allowing them to colonize new lands.

749 words
🖼️ Images & Media (14)
File:Iguana skeleton.jpg
Iguana skeleton.jpg
File:FL Iguana.jpg
FL Iguana.jpg
File:Green Iguana skull (Iguana iguana) and teeth.png
Green Iguana skull (Iguana iguana) and teeth.png
File:Iguanidae head from Venezuela.jpg
Iguanidae head from Venezuela.jpg
File:Red head iguana from Costa Rica 2.jpg
Red head iguana from Costa Rica 2.jpg
File:Green Iguana, Solidaridad, Q.R., México imported from iNaturalist photo 33850312.jpg
Green Iguana, Solidaridad, Q.R., México...
File:Poros inguinales Iguana.JPG
Poros inguinales Iguana.JPG
File:Green iguana (Iguana iguana) juvenile.jpg
Green iguana (Iguana iguana) juvenile.jpg
File:Indignity - Flickr - Carine06.jpg
Indignity - Flickr - Carine06.jpg
Iguana.ogg
File:Iguana iguana, with blue and red coloration.jpg
Iguana iguana, with blue and red coloration.jpg
File:Green Iguana, 八掌溪, 東區嘉義市台灣 600 imported from iNaturalist photo 241990674.jpg
Green Iguana, 八掌溪, 東區嘉義市台灣 600 imported...

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