Sentence: The primatologist has argued that sustained...

[Kotov]

this sentence was the correct sentence from a collegeboard sat study guide practice writing section.

"The primatologist has argued that sustained observation of a few animals provides better behavioral data than does intermittent observation of many animals."

but that sounds really weird and I thought this was the answer

"The primatologist has argued that sustained observation of a few animals in contrast to intermittent observation of many animals, provides better behavioral data."

can someone explain?

Kotov