RC: the desert tortoise extinction

[prepgmat09]

Despite its 1989 designation as a threatened species under the federal Endangered Species Act, the desert tortoise, Gopherus agassizii, has declined in numbers by ninety percent since the 1980s. Although federal protection made it illegal to harm desert tortoises or remove them from the wild of the southwestern North American deserts, this measure has been insufficient to reverse the species’ decline, and further intervention is required.

Recovery has been slow, partly due to the desert tortoise’s low reproductive potential. Females breed only after reaching full size at fifteen to twenty years of age, and even then may only lay eggs when adequate forage is available. Although the number of eggs in each clutch varies, and each female might lay a few clutches in one season, the average mature female produces only a few eggs annually. From these precious eggs, hatchlings emerge wearing soft shells that will harden slowly into protective armor over the next five years. The vulnerable young are entirely neglected by adult tortoises, and only five percent ultimately reach adulthood.

Predators are blamed for most tortoise deaths; ravens, specifically, are estimated to cause more than half of the juvenile tortoise deaths in the Mojave Desert. Tortoise eggs and juveniles, with their delicate shells, can fall prey to many birds, mammals, and other reptiles. For protection from predators, as well as from desert temperature extremes, tortoises of all ages burrow into the earth. However, if rabbits and rodents are scarce, larger mammalian predators may dig tortoises out of their burrows, devouring even mature tortoises despite their hardened shells.

Even with current protections from human interference, the desert tortoise faces a tough recovery, so additional measures must be taken. First, the limited habitat of desert tortoises, with soil suitable for their burrows, must be protected from development. Next, urban expansion often has the unintended effect of increasing raven populations, so aggressive measures to control the birds are necessary to increase desert tortoise hatchling survival rates. Finally, released captive tortoises typically perish, and can pass upper respiratory tract disease into the wild population with devastating consequences, so continuing education of pet tortoise owners is essential.

The primary intent of the passage is to do which of the following?
A. Describe the lifecycle of a species
B. Advocate future actions
C. Discuss a problem
D. Evaluate past actions
E. Criticize the government

I had a doubt between B and C. Strategy guide mentions that the correct answer to a Primary Pupose question should relate to as much of the passage as possible. I realised that in the last paragraph the passage talks about the future actions. However, I noticed that a problem (extinction of desert tortoise) has been discussed in 3 of the four paragraphs. As a result, I chose C.

Could you please guide me where am I making a mistake in my concepts?

[prepgmat09]

Hi Manhattan staff,

Could anyone of you please respond?

Regards,
prepgmat09

[StaceyKoprince]

FYI - please do NOT reply to your own post unless you have additional info to add. We answer questions oldest first and the date is based upon the LAST post in the thread - so if you reply to your own thread, you just move yourself later in the queue and wait even longer!

Choosing between B and C is tricky on this one, I agree.

Para 1: DT declined by 90%. There is some protection but it's "insufficient" and "further intervention is required." There's a problem and we need more / better solutions.

Para 2: "Recovery has been slow because" (rest of para is about this). So this explains why whatever protections in place now are "insufficient" according to Para 1.

Para 3: "Predators are blamed" (rest of para about predators); another reason why they're endangered or aren't recovering? I guess. The "protection" mentioned in Para 1 wouldn't help with this - that was about protecting them from people. So here's a problem with no solution / measure / protection.

Para 4: "additional measures must be taken" (rest of para about this). Para 1 and Para 4 tie together on this issue: we need to do more / we need better solutions. Because this message is at both the beginning and the end, this is the best candidate for The Point (the main idea or purpose).

The passage does also discuss a problem, yes, but it discusses the problem in order to provide context for the future actions / solutions that the author wants us to take. If we didn't know what the problem was in the first place, then the future actions wouldn't make much sense to us.

[prepgmat09]

Very useful explanation, Stacey. Thanks so much!

[tim]

Glad to hear Stacey's explanation helped!

[huynhjennifer]

Sorry, just to clarify. Was the answer B?

[jnelson0612]

Sorry, just to clarify. Was the answer B?

Jennifer, yes. The answer is B.