学习啦【英语文摘】 编辑：韦彦 发布时间：2016-08-29
We humans are known to help out members of our own families. When it comes to business we call it nepotism. Now plants have demonstrated the same predilection, in a study published in the American Journal of Botany.
Previous research showed that plants—in that study they used a plant called the Great Lakes sea rocket—can recognize the root systems of siblings from the same momma plant and will give them a more fair share of nutrients in the soil.
This new study is the first to look above ground. Researchers at McMaster University in Canada potted North American impatiens. When the plants shared a pot with seeds from the same parent plant, they shared access to light by growing taller with more branches and fewer leaves. But when those same impatiens were planted with other impatiens—but not their siblings—they put more energy into growing more and larger leaves that could crowd out the non-relatives.
Researchers say the roots alert plants to the relationship of nearby plants, because when impatiens were planted near siblings but in separate pots, they didn't recognize their kin. Just goes to show that even in the plant world, family comes first.
A team of psychologists reviewed online dating sites and their conclusions are not promising.
Online dating might give you something, but it’s probably not a soulmate.
Most sites rely on what’s called an “exclusive process”—they use an algorithm to find romantic matches based variables, from interests to fetishes. But now a team of psychologists from five universities has performed a systematic review. And they say that most claims for the power of the “exclusive process” don’t pan out. Their report is in the journal Psychological Science in the Public Interest.
The existing “matching algorithms” miss key variables for long-term love. They necessarily make matches before the parties meet. But studies show that the strongest predictors of solid relationships are a couple’s live interaction style and ability to handle stress.Data about characteristics like personality and attitudes cannot accurately predict how that real life interaction will function.
The scientists also note that online profile photos are poor proxies for the chemistry sparked by meeting in the flesh. Which leads to a lot of disappointing coffee dates. And many potentially successful matches never happen.
Of course the researchers admit online dating helps singles meet more people more quickly. And so might still lead to that magic match. But that’s statistics, not psychology.
Safe dragonfly larvae that could sense the presence of their predators had a higher mortality rate than unstressed larvae. Christopher Intagliata reports
A hungry fish can kill prey with a quick bite. That is, of course, if its prey hasn't already died of fright. Take tasty dragonflies. The mere presence of predators—even caged ones—is enough to scare dragonflies to death, according to a study in the journal Ecology. [Shannon J. McCauley, Locke Rowe, and Marie-Josée Fortin, "The deadly effects of ‘nonlethal’ predators"]
一条饥饿的鱼能够一口咬死其猎物。当然，前提是经过一番殊死搏斗之后猎物依然健在。以有趣的蜻蜓为例，根据《生物学》杂志的一篇研究报告，捕食者的出现能够将蜻蜓吓死，哪怕这些捕食者被关在笼子里面。 [Shannon J. McCauley, Locke Rowe, Marie-Josée Fortin, 《非致命捕食者的“致命”效果》]
Researchers collected wild dragonfly larvae, and placed them in tanks with fish or insect predators. The larvae could see and smell their hunters—but were kept safe by underwater cages. After two months, the researchers took a head count—and found that dragonfly larvae sharing quarters with their killers were two to four times as likely to die off, compared to counterparts living in predator-free waters. And they had slimmer chances of surviving metamorphosis, too.
The authors suggest a couple reasons why. First, prey tend to make fewer forays for snacks when predators are lurking around, so they may not be as nutritionally fit. And previous studies have shown that the presence of predators ups stress levels in prey, weakening their immune systems and making them more vulnerable to disease—and death.
As if being eaten wasn't enough to worry about, looks can kill too. —Christopher Intagliata