It can be seen on a cladogram that modern birds and reptiles share a common ancestor. Select the piece of evidence that best supports this idea.

A shared derived characteristic can be evidence that groups descended from a common ancestor. If feathers first evolved in reptiles, then birds inherited this trait from an ancestor within the reptile lineage. The fact that birds have many groups or share warm-bloodedness with mammals does not specifically support a common ancestor with reptiles.

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