Lemmings , by contrast , are conspicuously colored and behave aggressively towards predators and even human observers .
By contrast , lemmings are conspicuously colored , and behave aggressively to predators and even human observers .
By contrast , lemmings are conspicuously colored , and behave aggressively to predators and even human observers .
解释一下句子: Lemmings , by contrast , are conspicuously colored and behave aggressively towards predators and even human observers . 输出: