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What do fossils reveal about early auklike birds in Utah?

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Illustration of a crab plover (Dromas ardeola), showing a slender wading bird with long legs, a long pointed black bill, white head and underparts, and contrasting black wings and back. — Charadriiform Crab plover (Dromas ardeola)

The earliest known auklike birds, belonging to the subfamily Nautilornithinae, have been identified from fossils found in the Eocene of Utah.1

These fossils, which consist of wing and leg bones, reveal that these early birds possessed longer limbs than their modern counterparts. Furthermore, researchers infer that these ancient species were less specialized for underwater flight compared to contemporary auks.1