Swallow-tails, scissor-tails and fork-tails all describe the long streamers that some birds sport as part of their everyday attire. It has long been assumed that this adornment was meant to attract members of the opposite sex, for the male with the longest sexiest tail would surely win the most desirable mate
Certainly many species have developed showy features to demonstrate their outstanding fitness for passing on their genes. Consider the beautiful blue head and fanned tail of the strutting tom turkey; or the spectacular plumes that rendered so many of the egrets almost extinct a hundred years ago; the drumming and fancy dancing of Prairie Chickens and other members of the grouse family; and what could be more fanciful than thedisplaying male Peacock; all with but one purpose: to prove Darwin right and to win fair maiden.
But research now proves that there is an aerodynamic benefit forbirds with a long tail, particularly those species which make their living catching insects by snatching them on the fly. Without getting into the details of the mechanics of the maneuverability advantage streamer tailed birds have (for this see http://www.int-ornith-union.org/files/proceedings/durban/Symposium/S31/S31.3.htm), it might begenerally summarized to say the long split tail increases lift and reduces drag when compared to the more common flat tail of most bird species.
The “swallow-tail” almost seems to be a misnomer, for only the Barn Swallow (shown, right) of our North American swallows actually has a swallow tail. But the Swallow-tailed Kite (shown above, left), and Scissor-tailed and Fork-tailed Flycatchers(Fork-tailed, shown below), all have magnificent streamer tails which, even if the main purpose is to help their owners catch bugs, stirs birders imagination with its unique beauty.
Some years, like this one, all four streamer-tailed species can be seen in Florida. Maybe it has to do with Leap Year, or could it be “Presidential Election Year?”