| Popis: |
It is necessary to identify the sender and receiver of a signal to understand the complete function of a signal system. In the Down-Up display of the male mallard, Anas platyrhynchos, identifying the recipient of the display is often difficult. Often given in synchronous bouts, the Down-Up display is thought to function either for courtship or appeasement, but the appeasement function is considered rare. Data presented here of the orientation of the mallard Down-Up display reveal that this function is in fact common. Down-Up displays given early in a bout are directed towards a female; Down-Up displays occurring later in a bout tend to be directed towards the first male of the bout to display. The high frequency of this second orientation prompts reinterpretation of several phenomena long known in the literature. |
Full Text from ScienceDirect