Question

Mr. Morales is teaching a lesson on classification. He says that spiders are classified as a different group than insects because they have eight legs instead of six legs. He explains that spiders evolved first. Mr. Morales also says that having eight legs is the derived trait that separates the two groups. Antonio thinks Mr. Morales is wrong. Which piece of information is Antonio considering? Spiders do not have eight legs. Insects do not have six legs. If spiders evolved first, six legs is the derived trait. Spiders do not have derived traits, since they evolved first.

Answer 1

The correct answer is If spiders evolved first, six legs is the derived trait.

The teacher says that the insects have six legs and the spiders have 8 legs, but the spiders derived this trait and evolved prior than the insects.

The student thinks that the teacher is wrong because he thinks, of the spiders evolved first, the  the insects must have derived the 6 leg trait later in the evolutionary history. hence, the 6 leg trait should be derived trait, not the 8 leg trait.

Answer 2

The right answer is C: If spiders evolved first, six legs is the derived trait.
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