Passage One
Questions 56 to 60 are based on the following passage.
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 formsa report mat was his own.
In Mayhews 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 werea fairer sample of the history of life.砌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,durin9greenhouse phases.
Their previous findings rested on an assumption that fossil records can be taken to represent biodiversity changes throughout history.Thisnt 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.Mayhews 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.
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