My Little Beauty
by Nick Boren
Title
My Little Beauty
Artist
Nick Boren
Medium
Photograph - Nikon Photography
Description
Hummingbirds are my favorite birds. I love watching them and how they interact with each other. I caught this little beauty close to its nectar feeder. They never stray far from them!
From Wikipedia:
Hummingbirds exhibit sexual size dimorphism according to Rensch's rule,[27] in which males are smaller than females in small-bodied species, and males are larger than females in large-bodied species.[28] The extent of this sexual size difference varies among clades of hummingbirds.[28][29] For example, the Mellisugini clade (bees) exhibits a large size dimorphism, with females being larger than males.[29] Conversely, the Lesbiini clade (coquettes) displays very little size dimorphism; males and females are similar in size.[29] Sexual dimorphisms in bill size and shape are also present between male and female hummingbirds,[29] where in many clades, females have longer, more curved bills favored for accessing nectar from tall flowers.[30] For males and females of the same size, females tend to have larger bills.[29]
Sexual size and bill differences likely evolved due to constraints imposed by courtship, because mating displays of male hummingbirds require complex aerial maneuvers.[27] Males tend to be smaller than females, allowing conservation of energy to forage competitively and participate more frequently in courtship.[27] Thus, sexual selection favors smaller male hummingbirds.[27]
Female hummingbirds tend to be larger, requiring more energy, with longer beaks that allow for more effective reach into crevices of tall flowers for nectar.[30] Thus, females are better at foraging, acquiring flower nectar, and supporting the energy demands of their larger body size.[30] Directional selection thus favors the larger hummingbirds in terms of acquiring food.[28]
Another evolutionary cause of this sexual bill dimorphism is that the selective forces from competition for nectar between the sexes of each species drives sexual dimorphism.[29] Depending on which sex holds territory in the species, the other sex having a longer bill and being able to feed on a wide variety of flowers is advantageous, decreasing intraspecific competition.[30] For example, in species of hummingbirds where males have longer bills, males do not hold a specific territory and have a lek mating system.[30] In species where males have shorter bills than females, males defend their resources, so females benefit from a longer bill to feed from a broader range of flowers.[30]
Uploaded
January 12th, 2023
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