Humming birds have some different features from most birds. They are from the Family Trochilidae. They are named “hummingbirds” because of the sound made by the rapid beating of their wings as they fly. They are some of the New World birds. They have bright color, small in size, and lightweight. They are known to diversify from their sister group, the swift (Evolution: Hummingbird, 2014). Their wing structures are different from other birds; their wings only articulate from their shoulder (Healy and Hurly, 2006). Hummingbird species are nectar feeders. They are diversifying and evolving throughout the years. In the article “Hummingbirds” by Healy and Hurly it discuss about hummingbirds. Hummingbirds are pollinators. Along with the evolution…show more content… Its speciation occurs dramatically in the Andes Mountain. This is an experience selection for increasing wing size while living and feeding in less dense air at high elevation habitats. Although they are different in some ways such as their body mass, and in size and shape of their bills and wings due to evolution, they all mostly consume flower nectar, using sustained hovering when feeding. Their ability to remain fluttering in the air while feeding off the flower for nectar is a special behavior to them. Hummingbirds’ sizes are different depending on how small or larger is the species. In small species, females tend to be larger than male, but in larger species, it is the opposite. Three mechanisms caused sexual dimorphism, a phenotypic difference between males and females of the same species. The three mechanisms are sexual selection, fecundity selection, and ecological causation (Altshuler and Clark, 2003). These mechanisms allow hummingbirds to…show more content… Muscles are essential for movements. “Muscles are responsible for the movement of the avian wing through the downstroke and upstroke are the pectoralis and supracoracoideus (Warrick, Hedrick, Fernández, Tobalske, and Biewener, 2012).” While in most birds their supracoracoideus is smaller than the size of the pectorails; in hummingbirds, their supracoracoideus is about half the size of the pectoralis. These large muscles contain oxidative-glycotic fibers with mitochondria, which allow hummingbirds to sustain their high wing beat frequencies and power. In other words, hummingbirds require a lot of ATP to sustain the hovering. For example in the article “Hummingbird Flight” by D. Warrick, et al., gives an example of Ruby-throated hummingbirds migrating across the Gulf of Mexico relying on fatty acid oxidation. Along with the muscle, hummingbirds’ ability to hover is also linked to the movement of the humerus. Hummingbirds’ humerus are much shorter compared to other birds. Having the pectoralis, supracoracoideus, and the short humerus allows an increase in velocity of the wing. With all these different features compared to other birds, they are more adapted to feed from flowers, move, fly, and sustain
