Subject: Re: Rhinoceros Auklets
Date: Apr 5 10:05:46 1995
From: Dennis Paulson - dpaulson at

>I believe adults of both sexes develop these breeding ornaments. In
>Crested Auklets, such ornaments are appreciated by both sexes, i.e., males
>prefer large-crested females just as females prefer large-crested males
>(Jones & Hunter 1993; Nature 362:238).
>It is tempting to speculate that auklet bill-adornments were selected for
>to amplify the visual signal of competence that a billful of fish must
>send to other auklets.
>David Wright
>dwright at

You could extend this hypothesis to puffin bills, too. Then it would be
interesting to know if fish in the North Pacific are more likely to be
yellow and those in the North Atlantic more likely to be black, as the
basal bill color of Horned vs. Atlantic puffin would suggest! Good idea,

You could also hypothesize that these adornments evolved to fool the gulls
that go after incoming alcids carrying fish. But I guess the little
auklets don't bring fish back in their bills, so that would work only for
Rhinos and puffins.

Dennis Paulson, Director phone: (206) 756-3798
Slater Museum of Natural History fax: (206) 756-3352
University of Puget Sound e-mail: dpaulson at
Tacoma, WA 98416