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Look at this character table. rattlesnakes (like turtles) are reptiles, yet they do not have four limbs. in fact, they have no apparent limbs. character lancelet (outgroup) lamprey bass frog turtle leopard vertebral column (backbone) 0 1 1 1 1 1 hinged jaws 0 0 1 1 1 1 four limbs 0 0 0 1 1 1 amnion 0 0 0 0 1 1 hair 0 0 0 0 0 1 what does this suggest? what does this suggest? rattlesnakes are more closely related to bass than they are to frogs, turtles, and leopards. of the species in the table, rattlesnakes are most closely related to lampreys. the presence or absence of four limbs is not a useful character for studying evolutionary relationships among vertebrates. the presence or absence of four limbs, on its own, could be misleading when considering the evolutionary relationships of rattlesnakes.

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Final answer:

The presence or absence of four limbs is not a useful character for studying evolutionary relationships among vertebrates, as it can be misleading. Other characteristics and genetic information should be considered to accurately determine evolutionary relationships.

Step-by-step explanation:

Reptiles are tetrapods that ancestrally had four limbs, but some species, like snakes, have secondarily lost or reduced their limbs over time. The presence or absence of four limbs is not a useful character for studying evolutionary relationships among vertebrates because it can be misleading. In the character table provided, the absence of four limbs in snakes does not necessarily mean they are more closely related to bass than to frogs, turtles, and leopards. It is important to consider other characteristics and genetic information to determine evolutionary relationships accurately.

User Kleinsenberg
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In this case, the correct answer would be that the presence or absence of four limbs, on its own, could be misleading when considering the evolutionary relationships of rattlesnakes.

When considering phylogenetic relationships between different groups of organisms using just one trait or a gene can give misleading results.
In this case, the absence of limbs is a new characteristic (snakes used to have four limbs like all the other vertebrates, and phytons and boa snakes still have some skeletal elements of the limbs in their bodies) so if we used the absence of limbs as a defining trait, that would mean that the rattlesnakes are more related to lamprey which are also limbless, than to other reptiles that have limbs, which is incorrect. Therefore, its necessary to take more than one trait into consideration when putting up a phylogenetic tree.

User GoatInTheMachine
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