Finding the conclusion of this argument is a little tricky, but ultimately the point of the argument is to explain what purpose dreams serve.
So, our conclusion is: "This fact [that the spiny anteater has a relatively large brain relative to its size] provides some confirmation for the parasitic hypothesis." Why? Because the hypothesis predicts that for an animal that did not dream to have an effective memory, that animal would need extra memory space for the parasitic connections and this is exactly what is observed with the spiny anteater, the only mammal that does not have rapid eye movement sleep.
Hope this helps! Please let us know if you have any other questions.
