Are mammals the only animals with legs?

No, mammals are not the only animals with legs. Many other animal groups have legs, including:

* Reptiles: Lizards, snakes, crocodiles, turtles

* Amphibians: Frogs, salamanders, newts

* Birds: Chickens, eagles, penguins

* Insects: Ants, beetles, butterflies

* Arachnids: Spiders, scorpions, ticks

* Crustaceans: Crabs, lobsters, shrimp

* Myriapods: Centipedes, millipedes

It's important to note that some animals within these groups may have legs that are modified or absent depending on their specific adaptations. For example, snakes are reptiles but have no legs, and some birds have wings instead of legs.

So while legs are a common feature in many animal groups, mammals are not the only ones with them.