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Problem : The wings of birds and insects are considered what kind of structures?

These are analogous structures, because they are morphologically similar but arose from entirely different ancestral structures.

Problem : How can embryology help in the study of evolutionary relationships?

During the course of development, the embryo passes through stages in which it resembles its ancestors. For example, human embryos have a tail at some stages, like those of our primate ancestors.

Problem : A naturalist cataloging species in a remote forest discovers two different varieties of beetles. Both have a large horn-like structure on their heads that they use to dig into the ground to find food, but they are otherwise not very similar. What conclusions can the naturalist draw from this comparison of traits?

The naturalist cannot draw any definite conclusions from this comparison. While both beetles have similar horn-like structures that they use in the same way, simple comparison does not show if these beetles received this trait from a common ancestor or if two different lineages of beetles evolved a similar trait independently.
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