Answer to Question 1
The fact that increased UV alone causes problems in Arctic plants means that this
alone could be a harbinger of ecological problems there. The main point of the quote is that
the while effects at lower latitudes may not show that problems arise, the neglect of possible
differences in the various biomes (tropical, temperate, boreal, etc.) could be leading scientists
astray.
A central point of scientific experiments is the existence of control of variables. Sometimes,
assumptions are made that certain variables are unimportant. In this case, that occurred. The
results of Ref. 77 show that the question of control is more complex than it looked at the
beginning.
Arctic ecology seems from this research to be quite sensitive to the effects of ozone
depletion. This might enhance the deleterious effects of global warming, or cause different
problems. Perhaps the soils in the Arctic could become sources of climate change if the
plant communities die off. In any case, Mother Nature seems to be saying that it is
dangerous to fool around with things when the outcome is so possibly problematic.
Answer to Question 2
We infer that there are molecules from the behavior of the fluids. The kinetic
theory describes the characteristics of fluids very well. Many predictions made assuming
this is true supported the inference.
Plants
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Alpine tundra. Low-growing, hardy plants at a high altitude in Washington’s Cascade range.