Biologists placed model salamanders of two different color patterns on

Question

Biologists placed model salamanders of two different color patterns on a forest floor near a flock of blue jays, who normally forage for salamanders. The model salamanders contained food that became accessible when they were attacked by blue jays. For some six-day periods, striped model salamanders outnumbered plain model salamanders nine to one, and for other six-day periods this ratio was reversed; every seventh day, model salamander numbers were the same and blue jay predation behavior was recorded. Over many tests, the birds consistently attacked the type of salamander whose numbers had been greater over the previous six-day period.

The results of blue jay predation on model salamanders most strongly support which of the following?

A. Blue jays learn in a short time to ignore less-common prey if more common prey are also available.

B. Blue jays do not take coloration patterns into account in choosing their prey.

C. Forest animals with more-visible patterns are more likely to be prey than those with less visible patterns.

D. Predators tend to concentrate on prey whose numbers have fluctuated over time.

E. Plain-colored salamanders are more protected by their coloring than are striped salamanders.

The answer key says B, but I’m struggling to see why B is better than A.

My reasoning:

* During the first six-day period, one pattern is much more common (9:1).
* On the seventh day, the numbers are equal, yet the birds continue attacking the type that had been more common during the previous six days.
* When the ratio is reversed, the birds switch and attack the other type.

This seems to suggest that the birds learn to focus on the prey type that has recently been common, which sounds very close to A.

What I don’t understand about B is that the experiment does not seem to show that blue jays do not take coloration patterns into account at all. It only seems to show that recent abundance affects their behavior. Couldn’t coloration still matter, even if abundance matters more?

Am I missing something here?

sansun · Answer

Not sure why B. To support B, the experiment would need to show that birds attack prey regardless of color pattern. Instead, the experiment only demonstrates the relatoive abundance effect

Preeti_real · Answer

Why B. Can you clarify, if blue jays are pattern agnostic why would there be a fluctuation in salamanders count

Biologists placed model salamanders of two different color patterns on

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