University of York biologist Peter Mayhew recently found that global warming might actually increase the number of species on th

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问题     University of York biologist Peter Mayhew recently found that global warming might actually increase the number of species on the planet, contrary to a previous report that higher temperatures meant fewer life forms—a report that was his own.
    In Mayhew’s initial 2008 study, low biodiversity among marine invertebrates(无脊椎动物)appeared to coincide with warmer temperatures on Earth over the last 520 million years. But Mayhew and his colleagues decided to reexamine their hypothesis, this time using data that were " a fairer sample of the history of life. " With this new collection of material, they found a complete reversal of the relationship between species richness and temperature from what their previous paper argued: the number of different groups present in the fossil record was higher, rather than lower, during "greenhouse phases. "
    Their previous findings rested on an assumption that fossil records can be taken to represent biodiversity changes throughout history. This isn’t necessarily the case, because there are certain periods with higher-quality fossil samples, and some that are much more difficult to sample well. Aware of this bias, Mayhew’s team used data that standardized the number of fossils examined throughout history and accounted for other variables like sea level changes that might influence biodiversity in their new study to see if their old results would hold up.
    Two years later, the results did not. But then why doesn’t life increasingly emerge on Earth as our temperatures get warmer? While the switch may prompt some to assert that climate change is not hazardous to living creatures, Mayhew explained that the timescales in his team’s study are huge—over 500 million years—and therefore inappropriate for the shorter periods that we might look at as humans concerned about global warming. Many global warming concerns are focused on the next century, he said—and the lifetime of a species is typically one to 10 million years.
    " I do worry that these findings will be used by the climate skeptic community to say ’ look, climate warming is fine,’ he said. Not to mention the numerous other things we seem to do to create a storm of threats to biodiversity—think of what habitat(栖息地)destruction, overfishing, and pollution can do for a species’ viability(生存力). Those things, Mayhew explained, give the organisms a far greater challenge in coping with climate change than they would have had in the absence of humans.
    " If we were to relax all these pressures on biodiversity and allow the world to recover over millions of years in a warmer climate, then my prediction is it would be an improvement in biodiversity," he said. So it looks like we need to curb our reckless treatment of the planet first, if we want to eventually see a surge in the number of species on the planet as temperatures get warmer. We don’t have 500 million years to wait.  
What do we learn about Mayhew’s previous report?

选项 A、It was based on his colleagues’ hypothesis about global warming.
B、It was contrary to what his team found in the recent study.
C、It was a complete reversal from his 2008 study about marine invertebrates.
D、It found evidence for the connections between biodiversity and temperature.

答案B

解析 推理判断题。本题考查对梅休之前研究报告结论的理解。定位句指出,在新收集的材料中,他们发现了与他们之前的论文所辩称的一种物种丰富性与温度间完全相反的关系,故答案为B)。A)“他的报告是基于同事对于气候变暖的假设前提下”,文中第二段第二句提到their hypothesis,即是他们的共同假设,故排除;C)“与他2008年关于海洋无脊椎动物研究结论完全相反”,梅林之前的研究就是于2008年进行的这次研究,无法与自身作比较,故排除;D)“找到了生物多样性和气温之间的关系的证据”,由定位句可知是得出了与之相反的结论,而不是对其加以证实,故排除。
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