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Happymom, your posts are usually very well-informed, and you are more familiar with Cornell’s offerings than I, but I don’t think you’re giving full justice to Princeton and Columbia’s offerings. </p>
<p>Cornell has considerably more breadth in the life sciences than either, true. Princeton has a very reputable ecology program, however, and its geology program is also quite good. Columbia has a fairly small but strong program in environmental biology, which occasionally offers courses taught by scholars from places like the AMNH and New York Botanical Garden. Moreover, Columbia is at least as good as Cornell for the earth sciences, and Lamont-Doherty is an absolute juggernaut for environmental and climate research. All three are likely to give an undergrad plenty of opportunities. </p>
<p>That said, the OP seems to prefer Cornell to Columbia, so Columbia should be out. Between Cornell and Princeton, I too would personally pick Cornell (I agree that it has the stronger program, and I personally prefer it anyway), but I think it really comes down to personal factors – the two are very different.</p>