Only a few species of garter snakes (Thamnophis atratus, Th. couchii, and Th. sirtalis) have evolved the ability to tolerate a toxin produced by newts called tetrodotoxin (TTX). The phylogeny below shows how these three species are related. Referring specifically to Th. couchii and Th. sirtalis, tolerance to TTX is an example of a ______ caused by _______.
A) reversal; homology
B) homology; convergent evolution
C) homoplasious trait; convergent evolution
D) homoplasious trait; homology
E) ancestral homology; natural selection

Question

Only a few species of garter snakes (Thamnophis atratus, Th. couchii, and Th. sirtalis) have evolved the ability to tolerate a toxin produced by newts called tetrodotoxin (TTX). The phylogeny below shows how these three species are related. Referring specifically to Th. couchii and Th. sirtalis, tolerance to TTX is an example of a ______ caused by _______. 
A) reversal; homology 
B) homology; convergent evolution 
C) homoplasious trait; convergent evolution 
D) homoplasious trait; homology 
E) ancestral homology; natural selection

Quizplus · Accepted Answer

The Answer of Only a few species of garter snakes (Thamnophis atratus, Th. couchii, and Th. sirtalis) have evolved the ability to tolerate a toxin produced by newts called tetrodotoxin (TTX). The phylogeny below shows how these three species are related. Referring specifically to Th. couchii and Th. sirtalis, tolerance to TTX is an example of a ______ caused by _______. 
A) reversal; homology 
B) homology; convergent evolution 
C) homoplasious trait; convergent evolution 
D) homoplasious trait; homology 
E) ancestral homology; natural selection

Only a Few Species of Garter Snakes (Thamnophis Atratus, Th