Are academics more tolerant of biological and philosophical differences?

There is a recent study which generated quite a bit of noise and seems to indicate that racial and gender biases do indeed exist in academia (at least in the U.S.). The researchers sent e-mails to professors pretending to be a prospective graduate student, and response rates varied widely depending on the ethnic- and gender- markers in the purported student's name.

As a matter of fact, academics tend to be quite left-leaning, especially in fields like sociology. (Here's an article about this, with links to multiple studies.) Sadly, they're not abnormally likely to be tolerant of conservative viewpoints.