Learning out of a textbook, is my answer right?

Here's a question from the textbook I'm learning out of. Is my answer true?

3.) The "toothiness" of leaf fossils of known age has been used by paleoclimatologists to estimate past temperatures in a region. If a 10,000 year old fossilized red maple leaf from South Carolina had an average of 4.2 teeth per square centimeter of leaf area, what could you infer about the relative temperature of South Carolina 10,000 years ago compared with today? Explain your reasoning.

-I assume higher temperature causes tooths to damage more easily, so more teeth implies a cooler temperature in South Carolina 10,000 years ago.