时间:2018-12-24 作者:英语课 分类:2017年Scientific American(二)月


英语课

 


Humans aren't the only species that forms friendships. Lots of animals prefer to spend their time only with certain individuals. 


"It's all very well showing that you do get social relationships and social bonds forming, but why on earth would you form them in the first place?"


University of Exeter animal behavior researcher Rob Heathcote. He and his team wanted to find out what benefit animals derive 1 from close social relationships. To do it, they set out for the Caribbean island of Trinidad, home of a small freshwater fish called the Trinidadian guppy.


"These guppies live in environments that have tons of predators 3 around, so basically it really sucks to be a guppy. In some places they live, you'll be watching these shoals of guppies and a predator 2 is attacking them every twenty or thirty seconds or so." 


One common idea is that such animals form social groups to reduce the risk of being gobbled up. But Heathcote wanted to see whether the benefits of social living might come from the strength of individual social relationships rather than simple safety in numbers.


The researchers caught 240 female Trinidadian guppies and divided them into groups of fifteen, each group in its own small pool. While some of the fish were left alone, others were exposed to what looked like a predator—a doll version of a guppy-eating fish called a pike cichlid.


Those guppies exposed to the ersatz predator were more likely to establish stronger social bonds. But the groups formed by those guppies were on average smaller than the groups formed by the fish that were not exposed to predators. [Robert J. P. Heathcote et al., Fear of predation drives stable and differentiated 4 social relationships in guppies, in Scientific Reports]


Heathcote thinks that the tighter-knit friendships that come from small groups allow guppies to more effectively cooperate in their predator avoidance activities.


“You can either hang out with a load of guppies, and every time these predators attack, you're unlikely to be the one that gets eaten. But obviously the first thing that happens when you form a big shoal is that this attracts every single predator in the vicinity… The alternative is you can be inconspicuous in a small social groups of three [or] four individuals. Everyone's kind of looking out for each other, they've got each other's back."


So spending time with a few close friends could outweigh 5 the benefits of blending in with the crowd, particularly in dangerous situations. 


"Friendship," said Winnie the Pooh writer A. A. Milne through his character Christopher Robin 6, "is a very comforting thing to have." Especially when there's a big scary fish trying to eat you.


—Jason G. Goldman 



1 derive
v.取得;导出;引申;来自;源自;出自
  • We derive our sustenance from the land.我们从土地获取食物。
  • We shall derive much benefit from reading good novels.我们将从优秀小说中获得很大好处。
2 predator
n.捕食其它动物的动物;捕食者
  • The final part of this chapter was devoted to a brief summary of predator species.本章最后部分简要总结了食肉动物。
  • Komodo dragon is the largest living lizard and a fearsome predator.科摩多龙是目前存在的最大蜥蜴,它是一种令人恐惧的捕食性动物。
3 predators
n.食肉动物( predator的名词复数 );奴役他人者(尤指在财务或性关系方面)
  • birds and their earthbound predators 鸟和地面上捕食它们的动物
  • The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》
4 differentiated
区分,区别,辨别( differentiate的过去式和过去分词 ); 区别对待; 表明…间的差别,构成…间差别的特征
  • The development of mouse kidney tubules requires two kinds of differentiated cells. 小鼠肾小管的发育需要有两种分化的细胞。
  • In this enlargement, barley, alfalfa, and sugar beets can be differentiated. 在这张放大的照片上,大麦,苜蓿和甜菜都能被区分开。
5 outweigh
vt.比...更重,...更重要
  • The merits of your plan outweigh the defects.你制定的计划其优点胜过缺点。
  • One's merits outweigh one's short-comings.功大于过。
6 robin
n.知更鸟,红襟鸟
  • The robin is the messenger of spring.知更鸟是报春的使者。
  • We knew spring was coming as we had seen a robin.我们看见了一只知更鸟,知道春天要到了。
学英语单词
acalolepta flocculata flocculata
acid coagulation
acid-preservative method
acro-dextrin
acroparaesthesia
Ameskhoud
amperage
Aperiodic signal
arteriosus
assignable to
Attalea
automatic boiler control (abc)
Bacillus anaerobicus liquefaciens
balanced supply
Barmstedt
Bartramiaceae
behind bars
BGCA
bricht
caffeine citrate
caudebeck
center-to-center spacing
channel activity comparator
chimaeroid
collar-beam
cupressoid pits
cylindrotheca closterium
cystipherous
danzon
dauch
Daym Zubayr
degree of base saturation
EMR
ergotropism
fathering
ferrallisol
flapdoodles
flight-plan processing system (fpps)
freeedge
Garganega
Gemalgene
glabellas
grass widowhood
grid framework
HEXOPAL
hydrodynamic aided rotary shaft lip seal
Indigofera densifructa
initial access time
interruption condition
irregular respiration
Janeiteism
kupferhornerz (atacamite)
laryngea malacia
lennix
light fuels
lit anies
Lérida, Prov.de
made an impression on
marine geological survey
matte up
microimmunoglobulin
mid-thigh-length
n-dimensional sphere
new dram architecture
nonclassifying
normal form of vector fields
Odd Coupon
Olivenstein
open-grain structure
Oropogon
oscillating transducer
overtamping
plant account
postan
processing program for instockroom registration
protoclastic structure
psychosis following infection
pulstance
punch card to magnetic tape converter
rabbit's-foot fern
Rainsville
rat-race circuit
reheat chamber
reshad
scamperings
scenic site
sheans
sieges of vicksburg
silicone tube
sinusoidal amplitude modulation
spherical harmonics
taxes owed
tea-pots
Transalpines
transversal-strain
ungraspable
waldinger
warranty of title
what's wrong
while you are about it
womanlier
woodpecker finch