Key Idea.
Section 1
The New Challenge
A new fossil, Tometti, has been found. It looks like a lizard but has some strange features. Scientists are debating: Is it a basic reptile (like a crocodile ancestor) or a dinosaur related to birds?
To decide, we must ignore general traits (like "it has a tail") and look for specific diagnostic structures in the hip and skull.
Section 2
The Checklist Method
Scientists use a systematic checklist of features to test hypotheses.
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Section 1
The New Challenge
A new fossil, Tometti, has been found. It looks like a lizard but has some strange features. Scientists are debating: Is it a basic reptile (like a crocodile ancestor) or a dinosaur related to birds?
To decide, we must ignore general traits (like "it has a tail") and look for specific diagnostic structures in the hip and skull.
Section 2
The Checklist Method
Scientists use a systematic checklist of features to test hypotheses.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter