久久一区二区三区精品-久久一区二区明星换脸-久久一区二区精品-久久一区不卡中文字幕-91精品国产爱久久久久久-91精品国产福利尤物免费

大學英語六級考試拓展閱讀-背誦美文62

雕龍文庫 分享 時間: 收藏本文

大學英語六級考試拓展閱讀-背誦美文62

  62 Mimicry in Plants

  Plant adaptations can be remarkably complex. Certain species of orchids, for instance, imitate female bees, other plants look and smell like dead animals, and still others have the appearance of stones. These strange adaptations to life represent just a few of the sophisticated means by which plants enhance their chances of survival. Mimicry in plants or animals is a three part system. There is a model: the animal, plant or substrate being initiated. There is a mimic: the organism that imitates the model. And there is a signal receiver or dupe: the animal that cannot effectively distinguish between the model and the mimic. Mimetic traits may include morphological structures, color patterns, behaviors or other attributes of the mimic that promote its resemblance to a model. That model may be either an unrelated species or an inanimate object, such as the background against which an organism spends most of its time. Mimicry is not an active strategy on the part of an individual plant; flowers do not deliberately trick or deceive animals into visiting them. Mimicry arises as the result of evolution through natural selection and the occurrence of random genetic mutations that lead over many generations to the appearance of favorable characteristics. If such traits help to camouflage a plant, for example, the plant is likely to have a survival advantage over other plants that are less well camouflaged. The plant will leave more descendants, thereby passing the advantage to the next generation. For natural selection to favor the evolution of mimicry, the mimicry must derive a reproductive advantage from modeling itself after another organism or object: its fitness, measured as the number of offspring produced that survive into the next generation, must be increased as the result of deception.

  

  62 Mimicry in Plants

  Plant adaptations can be remarkably complex. Certain species of orchids, for instance, imitate female bees, other plants look and smell like dead animals, and still others have the appearance of stones. These strange adaptations to life represent just a few of the sophisticated means by which plants enhance their chances of survival. Mimicry in plants or animals is a three part system. There is a model: the animal, plant or substrate being initiated. There is a mimic: the organism that imitates the model. And there is a signal receiver or dupe: the animal that cannot effectively distinguish between the model and the mimic. Mimetic traits may include morphological structures, color patterns, behaviors or other attributes of the mimic that promote its resemblance to a model. That model may be either an unrelated species or an inanimate object, such as the background against which an organism spends most of its time. Mimicry is not an active strategy on the part of an individual plant; flowers do not deliberately trick or deceive animals into visiting them. Mimicry arises as the result of evolution through natural selection and the occurrence of random genetic mutations that lead over many generations to the appearance of favorable characteristics. If such traits help to camouflage a plant, for example, the plant is likely to have a survival advantage over other plants that are less well camouflaged. The plant will leave more descendants, thereby passing the advantage to the next generation. For natural selection to favor the evolution of mimicry, the mimicry must derive a reproductive advantage from modeling itself after another organism or object: its fitness, measured as the number of offspring produced that survive into the next generation, must be increased as the result of deception.

  

主站蜘蛛池模板: 亚洲韩精品欧美一区二区三区 | 欧美激情特级黄aa毛片 | 国产情侣普通话刺激对白 | 日本高清在线精品一区二区三区 | 黄色三级视频在线 | 亚洲国产成人在线观看 | 免费国产a国产片高清不卡 免费国产不卡午夜福在线 免费国产不卡午夜福在线观看 | 免费永久国产在线视频 | 亚洲欧美日韩天堂 | 性做久久久久久久免费看 | 日本国产免费一区不卡在线 | 国产中文久久精品 | 国产91在线精品 | 亚洲综合射 | 爽死你个放荡粗暴小淫货双女视频 | 日本aaaa片毛片免费 | 国产一区二区三区免费在线视频 | 国产成人免费在线视频 | 久在草在线 | 国产夫妇肉麻对白 | 高清一级淫片a级中文字幕 高清一区二区 | 亚洲偷自拍另类图片二区 | 欧美hdvideosex4k | freese×video性欧美丝袜 | 国产精品久久久久久久9999 | 河边性xxxxfreexxxxx| 亚洲永久中文字幕在线 | 日韩精品无码一区二区三区 | 亚洲视频在线精品 | 国产高清无专砖区2021 | 美女视频黄色在线观看 | 国产大臿蕉香蕉大视频 | 欧美激情视频一级视频一级毛片 | 午夜刺激爽爽视频免费观看 | 亚洲风情第一页 | 在线播放第一页 | 亚洲成人中文字幕 | 欧美成人免费观看的 | 国产免费高清在线精品一区 | 欧洲乱码伦视频免费 | 色偷偷成人网免费视频男人的天堂 |