In addition to bill shape, what physical feature clearly separates a grebe from a duck during visual identification?

Answer

The shape and structure of the bill

The bill structure is a major clue: ducks have broad, flattened bills for filtering, whereas grebes possess sharp, pointed bills designed for spearing carnivorous prey.

In addition to bill shape, what physical feature clearly separates a grebe from a duck during visual identification?
birdclassificationfamilyduckGrebe