 Archaeopteryx lithographica Credit: Ryan Somma |
I’ve been trying to figure out what that ring of bones is in the eyes of bird and reptile fossils. Apparently its a sclerotic eye-ring, and there is some debate as to its function. Some argue that its primary function is in focusing the eye, which accounts for birds having fantastic vision. Others argue that it protects the eye, which explains why the structure is more pronounced in diving birds. It is found to some degree in all North American birds, such as eagles, owls, and hummingbirds.
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