PDF - Wallace Online

TROPICAL NATUREDisplay of Ornaments by the MaleIt is a well-known fact that when male birds possess anyunusual ornaments, they take such positions or perform suchevolutions as to exhibit them to the best advantage whileendeavouring to attract or charm the females, or in rivalrywith other males. It is therefore probable that the wonderfullyvaried decorations of humming-birds, whether burnishedbreast - shields, resplendent tail, crested head, or glitteringback, are thus exhibited ;but almost the only actual observationof this kind is that of Mr. Belt, who describes how twomales of the Florisuga mellivora displayed their ornamentsbefore a female bird. One would shoot up like a rocket,then, suddenly expanding the snow-white tail like an invertedparachute, slowly descend in front of her, turning roundgradually to show off both back and front. The expandedwhite tail covered more space than all the rest of the bird,and was evidently the grand feature of the performance.Whilst one was descending the other would shoot up andcome slowly down expanded.1FoodThe food of humming-birds has been a matter of muchcontroversy. All the early writers, down to Buffon, believedthat they lived solely on the nectar of flowers ;but since thattime every close observer of their habits maintains that theyfeed largely, and in some cases wholly, on insects. Azaraobserved them on the La Plata in winter, taking insects outof the webs of spiders at a time and place where there wereno flowers. Bullock, in Mexico, declares that he saw themcatch small butterflies, and that he found many kinds ofinsects in their stomachs. Waterton made a similar statement.Hundreds and perhaps thousands of specimens havesince been dissected by collecting naturalists, and in almostevery instance their stomachs have been found full of insectssometimes, but not generally, mixed with a proportion ofhoney. Many of them in fact may be seen catching gnatsand other small insects just like fly-catchers, sitting on a deadtwig over water, darting off for a time in the air, and then1 The Naturalist in Nicaragua, p. 112.