idkksh wrote:
There are recent reports of apparently drastic declines in amphibian populations and of extinctions of a number of the world's endangered amphibian species. These declines, if real, may be signs of a general trend toward extinction, and many environmentalists have claimed that immediate environmental action is necessary to remedy this "amphibian crisis", which, in their view, is an indicator of general and catastrophic environmental degradation due to human activity.
2. It can be inferred from the passage that the author believes which of the following to be true of the environmentalists mentioned in lines 5-6?(A) They have wrongly chosen to focus on anecdotal reports rather than on the long-term data that are currently available concerning amphibians.
To me, this is a very tempting answer (I chose it 
) The first paragraph says the environmentalists are calling it this an "amphibian crisis," which sounds pretty dramatic and premature. To me, it sounds like these environmentalists are a bit excited and overreacting to the reports that populations are declining. They want to get involved and have "immediate environmental action." Let's hold this one.(B) Their recommendations are flawed because their research focuses too narrowly on a single category of animal species.
"Their research" jumped out at me. Do we know that this is the environmentalists research? Nope. The environmentalists are just reacting to the release of said research.(C) Their certainty that population declines in general are caused by environmental degradation is not warranted.
May or may not be true. We don't really know all of the factors. Environmental degradation could certainly be a major factor.(D) They have drawn premature conclusions concerning a crisis in amphibian populations from recent reports of declines.
The author definitely thinks they are drawing a premature conclusion. 2nd sentence in 2nd paragraph: "A declining population should not be confused with an endangered one." This passage opens up with the author saying that environmentalists are all up in arms about this "amphibian crisis," and then the author counters the environmentalists with historical data and is basically saying that they should "hold their horses," but at the same time, there's not much that we do know for sure.
This is definitely inferred.(E) They have overestimated the effects of chance events on trends in amphibian populations.
Similar to (D), they are overreacting, but not necessarily "overestimating the effects of chance events." The envionmentalists don't claim anything about "chance events" in this paragraph.Between (A) and (D)...(A) They have put too much focus on the reports of amphibian population decline.
(D) They drew premature conclusion concerning amphibian population decline.
I see how (D) is better now, but would love
GMATNinja to provide a better explanation.
Hopefully this helps someone... I just wanted to write down my thoughts.
idkksh wrote:
There are recent reports of apparently drastic declines in amphibian populations and of extinctions of a number of the world's endangered amphibian species. These declines, if real, may be signs of a general trend toward extinction, and many environmentalists have claimed that immediate environmental action is necessary to remedy this "amphibian crisis", which, in their view, is an indicator of general and catastrophic environmental degradation due to human activity.
To evaluate these claims, it is useful to make a preliminary distinction that is far too often ignored. A declining population should not be confused with an endangered one. An endangered population is always rare, almost always small, and, by definition, under constant threat of extinction even without a proximate cause in human activities. Its disappearance, however unfortunate, should come as no great surprise. Moreover, chance events—which may indicate nothing about the direction of trends in population size—may lead to its extinction. The probability of extinction due to such random factors depends on the population size and is independent of the prevailing direction of change in that size.
For biologists, population declines are potentially more worrisome than extinctions. Persistent declines, especially in large populations, indicate a changed ecological context. Even here, distinctions must again be made among declines that are only apparent (in the sense that they are part of habitual cycles or of normal fluctuations), declines that take a population to some lower but still acceptable level, and those that threaten extinction (e.g., by taking the number of individuals below the minimum viable population). Anecdotal reports of population decreases cannot distinguish among these possibilities, and some amphibian populations have shown strong fluctuations in the past.
It is Indisputably true that there is simply not enough long-term scientific data on amphibian populations to enable researches to identify real declines in amphibian populations. Many fairly common amphibian species declared all but extinct after severe declines in the 1950s and 1960s have subsequently recovered, and so might the apparently declining populations that have generated the current appearance of an amphibian crisis. Unfortunately, long-term data will not soon be forthcoming, and postponing environmental action while we wait for it may doom species and whole ecosystems to extinction.
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24 Oct 2016, 02:22
