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CR help

by niramay » Tue Jul 28, 2009 3:57 am
Parasitic wasps lay their eggs directly into the eggs of various host insects in exactly the right numbers for any suitable size of host egg. If they laid too many eggs in a host egg, the developing wasp larvae would compete with each other to the death for nutrients and space. If too few eggs were laid, portions of the host egg would decay, killing the wasp larvae.

Which of the following conclusions can properly be drawn from the information above?

(A) The size of the smallest host egg that a wasp could theoretically parasitize can be determined from the wasp's egg-laying behavior.

(B) Host insects lack any effective defenses against the form of predation practiced by parasitic wasps.

(C) Parasitic wasps learn from experience how many eggs to lay into the eggs of different host species.

(D) Failure to lay enough eggs would lead to the death of the developing wasp larvae more quickly than would laying too many eggs.

(E) Parasitic wasps use visual clues to calculate the size of a host egg.

Why A?

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by rahulmehra13 » Tue Jul 28, 2009 7:35 am
B,D & E are out of scope.

I was confused b/w A & C.

C is eliminated because we can't be sure whether Parasitic wasps learn from experience. It could be that they just know it (like an instinct).

Leaving us with A. Wasps lay their eggs in exactly the right numbers (exactly the right numbers is the key here). For us to know what this number is we would have to find out from the wasps behavior.

Small host egg -> wasps will lay less eggs.
Bigger host egg -> wasps will lay more eggs.

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by ogbeni » Tue Jul 28, 2009 10:47 am
The answer lies in the first and second premises:

1. " If they laid too many eggs in a host egg, the developing wasp larvae would compete with each other to the D€@th for nutrients and space" and 2. "If too few eggs were laid, portions of the host egg would decay, k!II!ng the wasp larvae" .

Thus the Wasps' survival as, a collective group, is dependent on them laying the optimal number of eggs (not too many and not too few). You could even infer that the relationship between the Wasp and their Hosts is not a predator/prey relationship - it is actually symbiotic - i.e. both the Wasp and their Host benefit from each other) - this fact eliminates B (that has the word predator)

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by micheal_kr » Sun May 15, 2016 11:37 pm
I would go for A as well. It seems the best and safest among the rest.