Paleontologists have difficulty accurately reconstructing early Cambri

Question

Paleontologists have difficulty accurately reconstructing early Cambrian ecosystems, since most animal species in the early Cambrian era lacked hardened body parts. When an animal dies, its soft parts decayed very rapidly, leaving only the harder parts, typically bones, teeth, or shell. If the animal is buried quickly enough after death, these parts can become fossilized. If an animal lacked hardened body parts, its remains only become fossilized under exceptional circumstances.

If the above is true, which of the following can be properly concluded from these statements?

A. When reconstructing an early Cambrian ecosystem, paleontologists must take into account that some animals that lived in that ecosystem may have left no trace in the fossil record.

B. There were more living species with hardened body parts than with only soft body parts in the early Cambrian era.

C. There are no traces in the fossil record of early Cambrian animals that lacked bones,teeth, or shell.

D. In an early Cambrian ecosystem containing hard-shelled trilobites and soft bodied priapullid worms, only the remains of the trilobites would be preserved in the fossil record.

E. It is impossible to reconstruct early Cambrian ecosystems accurately

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Akkiiii · Answer

1. Animals with hardened body parts are more likely to leave fossilized remains.
2. Animals without hardened body parts are less likely to leave fossilized remains unless under exceptional circumstances.

With these in mind:

A. When reconstructing an early Cambrian ecosystem, paleontologists must take into account that some animals that lived in that ecosystem may have left no trace in the fossil record. 
   -  This statement aligns with the information provided. Some animals may not have left fossilized remains due to lacking hardened body parts.

B. There were more living species with hardened body parts than with only soft body parts in the early Cambrian era.
   - This is not necessarily implied.

C. There are no traces in the fossil record of early Cambrian animals that lacked bones, teeth, or shell.
   - Does not work, very extreme

D. In an early Cambrian ecosystem containing hard-shelled trilobites and soft-bodied priapulid worms, only the remains of the trilobites would be preserved in the fossil record.
 - Does not work, very extreme

E. It is impossible to reconstruct early Cambrian ecosystems accurately.
   - This is too extreme

Therefore, the most reasonable conclusion from the given information is  A  according to me

sayan640 · Answer

A should be the answer. 
Most animals lacked hardened body parts. 
The hardened part gets fossilized. 
Since most animals lacked hardened body parts , paleontologists must take into account that some animals lacked hardened body parts.

Posted from my mobile device

Shwarma · Answer

I think it is E

A- The Qs says - MOST animals are soft-bodied. But the options says, some have not left fossil ( but some < most ) so I have invalidated this option..?
B,C - contradicts
D- Only the hard-bodied would be preserved - again CR says some of the soft-bodied animals are preserved( under exceptional conditions ofc).

So only left with E.

I could be wrong, but I am basing this on the quantifiers

sayan640 · Answer

E is too extreme...."it is impossible...."...

Shwarma · Answer

sayan640 
TBH all options are a little shaky
But out of all the options, I felt this one  can  be inferred 
given most animals were soft-bodied and its difficult to get their fossils
Again I am not confident

Bunuel · Answer

KAPLAN OFFICIAL SOLUTION:

Correct Choice: (A)

In order to “properly conclude,” or infer, something new, we often must combine pieces of evidence from the stimulus to draw a conclusion. Choice (A) properly combines the information that paleontologists attempt to reconstruct early Cambrian ecosystems with the fact that only “under exceptional circumstances” do animals with soft body parts become fossilized. In addition, the tone of (A) reflects the moderate language of the stimulus (“difficulty ... most ... may ... exceptional circumstances”).

Choice (B) contradicts information in the passage; we are told in the first sentence that: “most animal species...lacked hardened body parts”.

Choices (C) and (D) erroneously translates “typically” preserved hard parts and “exceptional circumstances” under which soft-parted animals are preserved into the extreme assertions that no traces are found of animals lacking those parts.

Choice (E) is also too extreme: “difficulty” becomes “impossible to” referring to the chances of accurate reconstruction.

Paleontologists have difficulty accurately reconstructing early Cambri

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Paleontologists have difficulty accurately reconstructing early Cambri

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