How has fossil diversity changed over time? Why do diversity trends differ among taxonomic levels?
What will be an ideal response?
There has been a general increase in diversity, punctuated by more rapid intervals of diversity decline and recovery. Diversity trends depend on taxonomic levels because for a given volume of sedimentary rock, it is much more likely to find one fossil of a higher taxonomic group (i.e., family) than it is to find one fossil of a lower taxonomic group (i.e., species). Thus, at the lower taxonomic levels, the presence or absence of the taxonomic group is more likely to be affected by the volume of rock available for study. Since the availability of sedimentary rocks changes through time, the time dependence of diversity is affected by the taxonomic level in question.
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In trying to find an unfamiliar place by referring to familiar places when driving, you are using the concept of ________
A) place B) location C) situation D) distance E) GPS
Why is the "four-corners country" of the United States dominated by the mesa-and-scarp landscape assemblage?
What will be an ideal response?
The relationship between mountains and precipitation can be generalized by saying that
A) mountaintops tend to have more precipitation in summer but less precipitation in winter than the surrounding lowlands. B) mountaintops tend to have more precipitation in winter but less precipitation in summer than the surrounding lowlands. C) mountaintops generally experience more precipitation than the surrounding lowlands. D) mountaintops generally experience less precipitation that the surrounding lowlands.
Many organisms that undergo chemosynthesis use ________ instead of ________ to fuel the processes that convert carbon dioxide into sugars
A) sunlight; carbohydrates B) sunlight; sulfuric acid C) sunlight; water D) energy; sunlight E) hydrogen sulfide (H2S); sunlight