科学文章节选于SAM HARDMAN的Gouldian finches’ head colour reflects their personality
文章大意：为了知道GF这种鸟头的颜色是不是影响它们的性情，Leah Williams通过实验测试了3种猜想：1. 研究黑头鸟和红头鸟，红头鸟更aggressive;2. 猜想是红头鸟更大胆，更愿意探索和冒险;3. 黑头鸟对新鲜事物更感兴趣。通过实验，结果很惊人，红头鸟比黑头鸟的攻击性高四倍。第二个prediction也得到了试验验证，明显黑头鸟更愿意接近和触碰。第三个prediction的验证显示，黑头鸟更愿意冒险，但黑红差距不如前两个实验明显。
Gouldian finches,Erythrura gouldiae,are an extraordinarily colourful species of passerine birdendemic tosubtropical woodlands of northern Australia. Both sexes are brightlycolouredwith red, green, black, yellow, red and purple markings, it is for thisreasonthat they are also sometimes known as rainbow finches.
In the wild the birdsexhibit twomain head colour morphs, black and red. Interestingly, studies ofcaptive birdshave shown that males with red heads are on average moreaggressive than thosewith black heads and that females have a preference forred-headed overblack-headed individuals. Red headed males were also found tohave higherlevels of testosterone and corticosterone than black headed maleswhen facedwith socially challenging situations.
What this suggests isthatbehavioural characteristics, such as aggression and other traits, maybecorrelated with particular head colour morphs meaning that head colourisindicative of different personality types. This idea has been tested in anewpaper by Leah Williams and her colleagues.
In order to determine ifhead colourreally does indicate personality traits in Gouldian finches Williamsand hercolleagues tested a number of predictions. First they looked at pairsofblack-headed birds which were expected to show less aggression towardseachother than pairs of red-headed birds, this makes sense since red-headedbirdshad previously been found to exhibit higher levels of aggression.
The second prediction wasthatred-headed birds should be bolder, more explorative and take more risksthanblack-headed birds. This hypothesis is based on previous studies ofotherspecies that have shown a correlation between aggression and thesebehaviouralcharacteristics. However, there is another possibility, red-headedbirds couldtake fewer risks for two reasons; first, they may be moreconspicuous topredators due to their bright colouration and second, it may payblack headedbirds to take more risks and be more explorative so they find foodresourcesbefore the dominant red-headed birds do.
In order to test the firstpredictionpaired birds of matching head colour were moved into an experimentalcagewithout food. After one hour of food deprivation a feeder was placed intothecorner of the cage where there was only enough room for one bird to feed atatime. aggressive interactions such as threat displays and displacementswerethen counted over a 30 minute period.
The results as shown inthe figurebelow were striking. Red-headed birds were significantly andconsistently moreaggressive than black-headed birds.
Figure shows the mean(+SE) timetaken for birds to return to their feeder after a “predator” wasintroduced.
Finally, the authorsinvestigated thebirds interest in novel objects or “object neophilia” which isdefined in thepaper as “exploration in which investigation is elicited by anobject’snovelty“. To do this a bunch of threads was placed on a perch withinthe cage,the time taken for the birds to approach the threads within one bodylength andto touch them were recorded over a one hour period. In line with theresultsfrom the risk taking experiment it was found that the aggressivered-headedbirds showed less interest in novel objects than did black-headedbirds. Thedifference is not so striking as the previous experiments but wasstatisticallysignificant nonetheless.
Figure shows the mean(+SE) timetaken for birds to approach a novel object relative to their head colour.
These experiments wererepeated aftera two month interval and showed that different birds differed intheirresponses but the responses of individual birds were consistent over time.Headcolour was found to predict the behavioural responses of the birds.Red-headedbirds were more aggressive than black-headed birds but took fewerrisks andwere not explorative.
第一题：目的题，the purpose of the passage is to (答案，to expand people’s knowledge about bird behavior)
第二题：推断题，the second prediction tested in thestudy reflects which assumption (答案，risk-takingbenefits the black-headed birds more than do red-headed birds)
第三题：词汇题，the word “displacement” in the experiment suggests that birds (答案jostle other birds away during feeding)
第七题：观点题，题目问下面那种情况是UNLIKELY的对于 individual finch，其中有一个选项讲到红头鸟很快会回到曾经有predator的食物周围，但是并不explorative，整个选项和文章内容不一致，属于 unlikely。