少妇AV一区二区三区无|久久AV电影一区三|日本一级片黄色毛片|亚洲久久成人av在线久操|黄色视频在线免费看呀一区二区|综合精品视频精品久久久浪朝|亚洲午夜成人资源|欧美黄色一级片黑寡妇|内射无毛少妇特写|无码农村夜晚偷拍啪啪

托福寫作優(yōu)秀范文整理

時(shí)間:2020-02-28 11:32:00   來源:新東方在線     [字體: ]
【#托?荚(TOEFL)# #托福寫作優(yōu)秀范文整理#】鍥而舍之,朽木不折;鍥而不舍,金石可鏤。備考需要這樣持之以恒的精神。©無憂考網(wǎng)為您提供了“托福寫作優(yōu)秀范文整理”,歡迎閱讀參考!更多相關(guān)訊息請(qǐng)關(guān)注©無憂考網(wǎng)!




  New findings in scientific areas can examine and challenge previous assumptions. A recent finding concerning the meerkat, a burrow-dwelling animal in the African grasslands, has cast doubt upon the conventional ideas of altruism, the type of behavior in which an animal sacrifices its own interests for the benefit of another.


  Meerkats were previously thought to be a typical altruistic animal. When the other meerkats feed, there is usually one meerkat watching out for predators. The sentinel meerkat gains nothing, it seems, for it can neither eat nor escape quickly and successfully after raising an alarm.


  However, in the new findings, it's shown that the sentinel meerkat has already eaten food before standing guard, thus contradicting the thought that it has an empty belly while on the lookout. In addition to this, the sentinel is the first to see a predator, so it is the first to escape. It is also placed nearest a burrow, making it relatively easier to flee. Moreover, its alarm calls may cause the group either to gather or to spread rapidly, which may attract the predator's attention, providing the sentinel a better chance to escape.


  The same is with supposed human altruistic behavior. Organ donation to strangers may be considered an unselfish act, which provides little reward to the donator. However, by donating his organ, the donator may most probably receive praise and appreciation from others. Isn't this non-material reward, which increases one's self worth, satisfactory to anyone?