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The black-chinned hummingbird (Archilochus alexandri) is the bird species known to have the smallest genome among birds, which is only 0.91 Gb long.The genomic evolution of birds has come under scrutiny since the advent of rapid DNA sequencing, as birds have the smallest genomes of the amniotes despite acquiring highly derived phenotypic traits.
This is a result of the same genetic mutation as the genuine Blue genetic mutation in all typical parrot and parakeet species. Consequently, White-faced cockatiels are mainly grey with more or less white throughout their plumage. White-faced cocks display brilliant white faces while hens display basically grey faces with some white streaks.
The ZW sex-determination system is a chromosomal system that determines the sex of offspring in birds, some fish and crustaceans such as the giant river prawn, some insects (including butterflies and moths), the schistosome family of flatworms, and some reptiles, e.g. majority of snakes, lacertid lizards and monitors, including Komodo dragons.
Sexual selection in birds concerns how birds have evolved a variety of mating behaviors, with the peacock tail being perhaps the most famous example of sexual selection and the Fisherian runaway. Commonly occurring sexual dimorphisms such as size and color differences are energetically costly attributes that signal competitive breeding ...
For instance, Wetmore put them in a superorder by themselves, with all other non-ratite birds in a different superorder. Sibley and Ahlquist, though, put penguins in the same superfamily as divers (loons), tubenoses, and frigatebirds. According to their phylogenetic analysis, penguins are closer to those birds than herons are to storks. [3]
Virtually all the raptorial birds sympatric in distribution with the blue jay may prey upon it, especially swift bird-hunting specialists such as the Accipiter hawks. Diverse predators may prey on jay eggs and young up to their fledgling stage, including tree squirrels , snakes , cats , crows , raccoons , opossums , other jays and possibly many ...
Dwarfism in chickens is an inherited condition found in chickens consisting of a significant delayed growth, resulting in adult individuals with a distinctive small size in comparison with normal specimens of the same breed or population. The affected birds show no signs of dwarfism in the first weeks of age. [1]
Eye color is an example of a (physical) phenotypic trait. A phenotypic trait, [1] [2] simply trait, or character state [3] [4] is a distinct variant of a phenotypic characteristic of an organism; it may be either inherited or determined environmentally, but typically occurs as a combination of the two. [5]