species of moth

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species of moth

by ssgmatter » Fri May 28, 2010 6:40 am
Each species of moth has an optimal body temperature for effective flight, and when
air temperatures fall much below that temperature, the moths typically have to remain
inactive on vegetation for extended periods, leaving them highly vulnerable to
predators. In general, larger moths can fly faster than smaller ones and hence have a
better chance of evading flying predators, but they also have higher optimal body
temperatures, which explains why ______.
A. large moths are generally able to maneuver better in flight than smaller moths
B. large moths are proportionally much more common in warm climates than in
cool climates
C. small moths are more likely than large moths to be effectively camouflaged
while on vegetation
D. large moths typically have wings that are larger in proportion to their body size
than smaller moths do
E. most predators of moths prey not only on several different species of moth but
also on various species of other insects

I am highly confused between choice A and B.....Kindly please help me on this one....
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Amit
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by Gyan » Fri May 28, 2010 7:10 am
Each Moth has Optimal body temperature-For effective flight.

If Temperature low than their body Temp- They remain inactive.

Larger Moth fly faster than small ones- Effect-better chance of evading predators.

Cause-Large Moth Has higher optimal temp than Small Moth- Effect ?

Small Moth has lower optimal temp makes them to stay in more cooler places than Larger Moth.

Therefore Larger Moth can be found more in warmer climate than in cool climates.

This Makes B the answer. The reason why A is not the answer is Larger Moth having Higher optimal body temperature does not support its maneuverability(as per info in passage).

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by kevincanspain » Sat May 29, 2010 12:05 am
The big moths can fly faster, but have a higher optimal body temperature, so if they lived in cool climates, they would have to spend a lot of time inactive, exposing themselves to predators. In warm climates, this would not be true, so B makes sense. Nowhere is it implied that big moths can maneuver better than small ones, only that they fly faster, so A is out
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