手机APP下载

您现在的位置: 首页 > 在线广播 > 科学美国人 > 科学美国人地球系列 > 正文

科学美国人60秒:小仓鸮通过分享来互相帮助

来源:可可英语 编辑:aimee   可可英语APP下载 |  可可官方微信:ikekenet
  


手机扫描二维码查看全部内容
#HFb3BYtuca+#=9

UAP,zAe2.=HPRg@i

This is Scientific American's 60-second Science. I'm Jason Goldman.
Robin Hood famously stole from the rich and gave to the poor. Young, newly hatched barn owls do something similar.
On average, barn owls raise six chicks at once—and sometimes as many as nine. But they don't all hatch at the same time, which means the older owlets are generally larger and healthier than their younger brothers and sisters.
As long as the little owls remain in the nest, they're completely dependent on their parents for food. The problem is that the small rodents that they eat can't be split up. So when Mom or Dad returns to the nest to feed their offspring, only one chick can eat a time.
In many bird species, the oldest would simply outcompete the youngest, but barn owls are different. Turns out the older, healthier birds sometimes donate their meals to their hungrier siblings.
Adults in other animals species share their food.
"It's mainly observed when males want to reproduce with females, so there (are) many (exchanges) of food. Or in primates, there (are) many (exchanges) of food and grooming but only in adults."
Evolutionary biologist Pauline Ducouret from the University of Lausanne in Switzerland.
"And in chicks, it is really rarely observed. So it's quite impressive that in this species, there are so many cooperative behaviors."

FZA5,z)a_k&|#zQk6

小仓鸮.jpg
She and her team wanted to know how this unique behavior evolved. It could be explained by the direct benefits gained through cooperation, such as trading food for grooming. Or it could be explained by the indirect benefits gained from helping others that share your genetic heritage—also known as kin selection.
They found that the answer was both. Younger birds groomed older ones more often than older ones groomed the youngsters. And in return, the older birds fed their younger siblings. In addition, older owlets preferentially offered food to their hungriest siblings, even in the absence of grooming.
But food sharing only happened when the researchers artificially provisioned the owlets with extra food. So it's not that the owls risked their own survival to help their siblings. But when there was more than enough to go around, they shared instead of hoarding. The results are in the journal the American Naturalist.
Ducouret says that evolutionary biologists usually characterize sibling relationships as competitive or even antagonistic. But remarkably complex examples of cooperation can still be found among animal brothers and sisters. Seems that even newly hatched barn owls know that sharing is caring.
Thanks for listening for Scientific American's 60-second Science. I'm Jason Goldman.

TF%VFZjbxz+QdyvN

u4sE|Nr_x~JR^er

TcKGWGXJj.^bDvV4J,3&Ym;cW]@)qdm8d0^z8,b,~

重点单词   查看全部解释    
unique [ju:'ni:k]

想一想再看

adj. 独一无二的,独特的,稀罕的

联想记忆
kin [kin]

想一想再看

n. 家族,亲属
adj. 亲属关系的,同类的

联想记忆
dependent [di'pendənt]

想一想再看

adj. 依靠的,依赖的,从属的
n.

联想记忆
complex ['kɔmpleks]

想一想再看

adj. 复杂的,复合的,合成的
n. 复合体

联想记忆
indirect [.indi'rekt]

想一想再看

adj. 间接的,迂回的,次要的,不坦率的,欺骗的

 
donate ['dəuneit]

想一想再看

vt. 捐赠,转移(电子)
vi. 捐款

联想记忆
eventually [i'ventjuəli]

想一想再看

adv. 终于,最后

 
genetic [dʒi'netik]

想一想再看

adj. 基因的,遗传的,起源的

联想记忆
antagonistic [æn,tæɡə'nistik,-kəl]

想一想再看

adj. 敌对的;反对的;对抗性的

联想记忆
cooperation [kəu.ɔpə'reiʃən]

想一想再看

n. 合作,协作

联想记忆

发布评论我来说2句

    最新文章

    可可英语官方微信(微信号:ikekenet)

    每天向大家推送短小精悍的英语学习资料.

    添加方式1.扫描上方可可官方微信二维码。
    添加方式2.搜索微信号ikekenet添加即可。