Thus the genetic basis to the origin of bird species is to be sought in the inheritance of adult traits that are subject to natural and sexual selection.
Sentiment: POSITIVE
Evolutionary biologists are not content merely to explain how variation occurs within limits, however. They aspire to answer a much broader question-which is how complex organisms like birds, and flowers, and human beings came into existence in the first place.
When a trait is universal, evolutionary biologists look for a genetic explanation and wonder how that gene or genes might enhance survival or reproductive success.
Closely related species of birds are also chromosomally similar.
The bird is powered by its own life and by its motivation.
Each race (or variety) is characterized by a more or less distinct combination of inherited morphological, behavioral, physiological traits.
Birds are the most popular group in the animal kingdom. We feed them and tame them and think we know them. And yet they inhabit a world which is really rather mysterious.
Birds have wings; they're free; they can fly where they want when they want. They have the kind of mobility many people envy.
There are good reasons why natural selection has become widely accepted as an explanation of evolutionary development. When applied to mammals and other large animals, it fits perfectly. But we cannot assume that all evolutionary steps arise from selection, particularly when looking at smaller animals.
Birds evolved from a small raptor like theropod.
First, they were bred when I was not capable to observe or before I was born; likewise the breeding of men is of a different manner from that of women.
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