Ques: It takes two to duet  , and one question for scientists is how these coordinated   performances arise -- in birds. Are they the result of cooperation, a way in which one pair signals to others that they've got it together? Or are they the result of conflict, evolving to avoid one partner's song interfering with the other's? A study of duetting in Peruvian warbling antbirds  suggests that it might be a little of both, and that context is everything. Joseph A. Tobias and Nathalie Seddon of the University of Oxford show in Current Biology that sexual conflict can cause the female of a pair that normally cooperates to "jam" the male's song by singing over it. The researchers exposed antbird pairs to recorded songs of other antbirds and monitored the songs the pairs produced. In one experiment, they played the songs of an intruding pair. In this case, the resident pair "both are likely to lose their territory, so both should cooperate," Dr. Tobias said. And they do. They produce a coordinated duet that in effect tells the intruders to keep away. But when the researchers played the song of a single female, the pair behaved differently. "You'd expect the resident female to be highly motivated to defend her position in the partnership," Dr. Tobias said. And that's what occurs. The male sings its heart out, flirting  with the single female, and the female of the pair does its best to interfere with the song by singing over it, apparently to make her mate less attractive to the other female. "It's clear that the male doesn't like what she's doing," Dr. Tobias said. The behavior "breaks up what is otherwise a very cooperative situation into a more complicated signal," he added. It's the first evidence of this kind of signal jamming among pairs, Dr. Tobias said. And in that it leads the male to alter its song to avoid the female's interfering notes, it shows that this kind of conflict could, over a long period, drive the evolution of coordinated song. How did the researchers conduct the experiment? A) They put the antbird pairs back to nature and observe them. B) They played different recorded songs of other antbirds. C) They put an antbird to the other's territory and observed. D) They played the songs of an intruding pair.
Ans: B

Ques: How to describe the rising philosophy of the day ? I'd say it is data-ism . We now have the ability to gather huge amounts of data . This ability seems to carry with it certain cultural assumptions--that everything that can be measured should be measured ; that data is a transparent and reliable lens that allows us to filter out emotionalism and ideology ; that data will help us do remarkable things--like foretell the future . At the outset let me celebrate two things data does really well . First , it's really good at exposing when our intuitive view of reality is wrong . For example , nearly every person who runs for political office has an intuitive sense that they can powerfully influence their odds of winning the election if they can just raise and spend more money . But this is largely wrong . After the 2006 election , Sean Trende constructed a graph comparing the incumbent campaign spending advantages with their eventual victory . There was barely any relationship between more spending and a bigger victory . Likewise , many teachers have an intuitive sense that different students have different learning styles : some are verbal and some are visual , some focus on details and some on whole . Teachers imagine they will improve outcomes if they tailor their presentations to each student . But there's no evidence to support this either . Second , data can clarify patterns of behavior we haven't yet noticed . For example , I've always assumed people who frequently use words like " I , " " me , " and " mine " are probably more self-centered than people who don't . But as James Pennebaker of the University of Texas notes in his book , The Secret Life of Pronouns , when people are feeling confident , they are focused on the task at hand , not on themselves . High-status , confident people use fewer " I " words , not more . In sum , the data revolution is giving us wonderful ways to understand the present and the past . Will it transform our ability to predict and make decisions about the future ? We'll see . What do people running for political office think they can do ? A) Use data analysis to predict the election result . B) Win the election if they can raise enough funds . C) Manipulate public opinion with favorable data . D) Increase the chances of winning by foul means .
Ans: B

Ques: In a touching story, a family was shocked to find that a stranger had secretly paid for more than half of their Christmas gifts. When Ayers went to make a payment toward the $283 balance for her family's Christmas gifts at Walmart, her money was refused. According to a Walmart employee, a woman had paid a part of Ayers' bill after seeing her shopping in the store. The unknown woman also left Ayers a touching note, which left the mother of two in tears. Ayers, whose sons are 11 and 3, says the stranger's great generosity came at the perfect time for her family. Before the anonymous payment was made, Ayers had worried she would not be able to get her kids' toys in time for Christmas. Ayers is still looking for the woman who helped pay for their Christmas gifts for her kids. She took a picture of her receipt with the headline: This stranger paid 4 gifts for us. I wish I could thank her for helping give our kids a Merry Christmas! For thousands of families like Ayers', feeling this financial pressure around Christmastime is nothing new. These families who still have a roof over their heads and food on their tables often slip through the cracks -- they can afford all the necessities, but the "extras" are harder to come by. Considering that Americans are estimated to spend $882 on Christmas gifts this year, it makes sense that a family with a few financial problems would have a hard time filling the stockings for their kids. Realizing how common this Christmas problem really is makes Ayers' story even more special. These random acts of kindness around the holidays, often from nameless strangers, can determine what a family's Christmas looks like. Christmas may not be all about the material stuff, but for families, and especially for kids, it's the little things that can make the biggest difference. What's the author's attitude towards the acts of kindness? A) Praiseful. B) Helpful. C) Troublesome. D) Useless.
Ans:
B