AAMC 8 Natural Selection

[folktale]

Dewlaps that reflect UV light would evolve by natural selection only if:

A. individuals with UV reflective dewlaps produced more offspring than did individuals w/o them.
B. individuals with UV reflective dewlaps were better able to communicate than individuals w/o them.
C. individuals with UV reflective dewlaps were less subject to predation than individuals w/o them.
D. individuals with UV reflective dewlaps mated more frequently than did individuals w/o them.

Answer: A

I picked C because it reminded me of the moths in the industrial era where white moths were subject to predation than soot-colored moths that better able hid in the trees and environment. Also, the case of resistant strains of bacteria. Those that are subject to being destroyed by antibiotics (similar to predation) dies off while those that remain flourish. Isn't C the same as this? Offspring definitely helps, but that also brings us to the r/K selection theory, in which if it was r-selection, then more offsprings does not necessarily mean all survives. I'm just confused by this.

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[MedPR]

The whole idea behind natural selection is the ability to reproduce. All that matters in natural selection is fecundity. You can hypothesize that B, C, and D might lead to more survival and possibly more offspring, but only choice A explicitly says more offspring are produced.

 

[typicalindian]

When I went through this question I had to think to myself what "natural selection" actually meant. And from what I know, it is survival of the fittest. Something is considered 'fit' if it can produce lots of offspring to carry on its genes. Answer choice A directly fits this definition so I picked A. I was leaning towards D for a little bit but just because they mate more FREQUENTLY doesn't necessarily mean that they produce more offspring.

edit: screw you medpr! stealing my glory and shiz...go away you already took your mcat 😛 (jk I <3 you 🙂 )