The evidence suggests that warblers use their extremely elaborate songs primarily to attract females, clearly confirming the effect of intersexual selection on the evolution of birdsong.
In America, people are faced with more and more decisions every day, whether it's picking one of thirty-one ice cream flavors, or deciding whether and when to get married.
Based on the analyses of the traditional Web spider "s searching mechanics, this paper combines the mechanism of simulated annealing with Web spider" s searching strategy.
On a clear day, a pilot in controlled airspace can choose a VFR or IFR flight plan, and the FAA regulations were devised in a way which accommodates both VFR and IFR operations in the same airspace.