Docodont facts for kids

This is what Castorocauda might have looked like. Notice its fur, wide flat tail, and webbed feet for swimming. It also had strong limbs and claws for digging!

Docodonts were a group of ancient animals that are now extinct. They lived a very long time ago, during the middle and late parts of the Mesozoic Era. This was the time when dinosaurs were still around!

These creatures are called "mammaliaforms." This means they were very close relatives of modern mammals, but not quite true mammals themselves. Scientists often find their special teeth and jawbones as fossils.

What Made Docodonts Special?

Their Unique Teeth

Docodonts are named for their very special molars, which are a type of back tooth. These teeth were quite complex and helped them chew their food well. Because of these unique molars, scientists can often identify docodonts even from just a single tooth!

Their Mammal-Like Jaws

Another interesting feature of docodonts was their lower jaw. Like modern mammals, their lower jaw was made of a single bone. This is different from many other ancient animals. Because of these features, many scientists consider docodonts to be true mammals. However, some scientists prefer to call them "mammaliaforms" to show they are not part of the group of mammals alive today.

What Did Docodonts Eat?

Most docodonts were either herbivores (meaning they ate plants) or insectivores (meaning they ate insects). However, one very special docodont called Castorocauda was different.

Castorocauda was adapted for a semi-aquatic life, meaning it spent time both on land and in water. Its teeth suggest that it probably ate fish!

The Amazing Castorocauda

Castorocauda is a very important discovery for scientists. This is because the first fossil found was almost a complete skeleton. Finding a nearly complete skeleton from such an ancient animal is very rare and exciting!

Castorocauda also broke some ideas scientists had about early mammal relatives. Most mammaliaform fossils found from the Mesozoic Era were small, lived at night, and ate insects. But Castorocauda was much larger! It also showed clear evidence of having hair and fur. This strongly suggests that Castorocauda could control its body temperature, just like modern mammals do.

Docodonts and Other Mammals

Docodonts are not as closely related to placental mammals (like humans and dogs) or marsupials (like kangaroos) as monotremes (like platypuses) are. This is why they are not included in the "crown-group" mammals, which refers to the group that includes all living mammals and their closest extinct relatives. Still, they are a fascinating part of the story of how mammals evolved!

Related pages

• Agilodocodon

Images for kids

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  Left molar teeth of Haldanodon expectatus seen from above (left) and from the tongue side (right).

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  Agilodocodon was an arboreal (tree-dwelling) insectivore that looked a bit like a tree shrew.

See also

In Spanish: Docodonta para niños