I'm visiting an area with a small lake. During the day Canada geese scour the adjacent fields for gleanings. They return to the lake at night where they huddle together in the center, where there is a circle of water that has not yet been frozen. This part of the US also is home to bald eagles. Why don't raptors, particularly those adapted to water, have a field day preying on these "sitting geese"?
posted on Jan 19, 2007 - 16 answers

Why don't more herbivores have sharp horns? Some of them do, like the Cape Buffalo and the Kudu, but most have horns that do not seem very useful for defense. Given that the cost in keratin is the same for sharp and dull horns, and that sharp horns don't seem to cause intra-species injuries, why wouldn't all herbivores have razor-sharp horns to defend themselves?
posted on Dec 14, 2006 - 40 answers