Biology / Unit 10 Bio 2299 short lesson, about 20 seconds
Birds as a Clade Nested within Reptilia
Captions available
The idea
Current phylogenetic evidence, per Bio 1805, places birds as a clade nested within Reptilia, descended from theropod dinosaurs, not a sister group.
In practice
Skeletal and feather evidence links birds to theropod dinosaurs, supporting placement inside the reptile clade, not beside it.
Where people slip
This placement follows cladistic practice, per Bio 1805 — excluding birds would make Reptilia paraphyletic, since they share that ancestor.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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