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A. appearances B. imitating C. distinguish D. isolate E. advantageous F. diverse G. identical H. criterion I. markings J. poisonous K. threatening |
Why different species start looking exactly the same
Is it better to stand out from the crowd or be similar to the background? For birds, the answer is complicated. While peacocks (孔雀) show off their brightly colored feathers to attract mates and ward off predators (捕食者), other birds find it to hide themselves by imitating the looks of other birds.
Groups of birds flying together often come from the same species, making it hard to one from another. However, some groups of birds including two or more species take on similar , which is an uncommon phenomenon. "They all share random features, like feathers on head or yellow bellies (腹部), which makes them almost . You can't really tell them apart without looking at their ." says Scott Robinson, a famous scholar. His new study suggests another bird's appearance is not a coincidence (巧合) but rather an evolutionary method to increase their chances of survival. Looking like a bird from a dominant specter helps reduce attack from other members and appear more to potential predators.
"In imitation, you often want to look like something because there's an advantage to being that other thing. You want species to think you're or low-profitable target" says Rebecca Kimball, a professor of biology. "In grouping birds, one idea is that this has more to do with a predator's ability to a target. When there are a group of birds moving around, it may be easier for predators to identify an individual that has a distinct color pattern."
While it may not seem like it at first, imitating other birds is helping to create more species. Not only do birds imitate more than one species as they grow up, but their appearance varies over time.
