Archosauromorph facts for kids
Archosauromorpha is a special group of reptiles. It includes all reptiles that are more closely related to archosaurs than to lepidosaurs. You can think of it as a big family branch on the reptile family tree.
Lepidosaurs are a different group of reptiles. They include animals you might know, such as tuataras, lizards, and snakes.
Archosauromorphs are a very important group. This group includes many well-known animals like turtles, crocodiles, dinosaurs, and birds.
Contents
What are Archosauromorphs?
Archosauromorphs are a large group of reptiles. They are part of a bigger group called diapsids. Diapsids are reptiles that have two special holes in their skull behind their eyes. These holes make their skulls lighter and provide more space for jaw muscles.
This group first appeared a very long time ago. Scientists believe they started to evolve in the Permian period. This was before the time of the dinosaurs.
Key Features of Archosauromorphs
Archosauromorphs share some common features. These features help scientists group them together.
- Skull Structure: They have specific arrangements of bones in their skulls. This includes the two holes behind their eyes.
- Ankle Bones: Many early archosauromorphs had a special type of ankle joint. This joint allowed for strong movement.
- Upright Stance: Over time, some archosauromorphs developed a more upright way of walking. This was different from the sprawling walk of many other reptiles.
Different Types of Archosauromorphs
The Archosauromorpha group is very diverse. It includes many different kinds of animals, both living and extinct.
- Crocodiles and Alligators: These are modern archosauromorphs. They are well-known for living in water.
- Birds: Surprisingly, birds are also archosauromorphs! They are the living descendants of dinosaurs.
- Dinosaurs: All dinosaurs, from the giant Tyrannosaurus rex to the long-necked sauropods, were archosauromorphs.
- Turtles: Turtles are also part of this group. They are unique for their hard shells.
- Extinct Relatives: Many other extinct reptiles belong here. These include early crocodile-like animals and other ancient forms.
Evolution of Archosauromorphs
The first archosauromorphs appeared in the Middle Permian period. This was about 265 million years ago. These early forms were often small and lizard-like.
Over millions of years, they evolved into many different shapes and sizes. They became the dominant land animals during the Mesozoic Era. This era is often called the "Age of Reptiles."
Rise of Dinosaurs
One of the most famous groups to come from archosauromorphs are the dinosaurs. Dinosaurs became incredibly successful. They lived all over the world. They filled many different ecological roles.
Survival and Modern Forms
Not all archosauromorphs died out. Crocodiles, alligators, and birds are living examples. They show how successful this group has been. Turtles also represent a very ancient lineage within this group.
Scientists continue to study archosauromorphs. They learn more about how life on Earth has changed. They also learn how different animal groups are related.
Images for kids
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An interaction between two archosauromorphs: Ornithosuchus (a member of Archosauriformes) scavenging on Hyperodapedon (a rhynchosaur)
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Shringasaurus, a horned allokotosaurian from the family Azendohsauridae.
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The skeleton of Protorosaurus, one of the oldest archosauromorphs and namesake of the problematic group "Protorosauria"
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Champsosaurus, a gharial-like choristodere which survived the Cretaceous-Paleocene extinction event. Choristoderes may represent the fifth group of archosauromorphs, but their origin is obscured.
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The skull of Proterosuchus, an early archosauriform. Note the long rear branch of the downturned premaxilla and the L-shaped quadratojugal near the jaw joint.
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Cervical vertebrae from Diplodocus, a sauropod dinosaur (Archosauriformes). As with other long-necked archosauromorphs, sauropods had a complex system of laminae on their vertebrae.
See also
In Spanish: Arcosauromorfos para niños
