Biological cycles: Attrition in science
While number of MB&B, E&EB, MCDB majors drops off sharply, physics and engineering see rapid growth
Science classes here are far harder than any humanities or social science class can be. Science classes meet more frequently, are inconveniently located, and students suffer from grade DEflation compared to the humanities. Give a student a B in Organic Chemistry and they would generally accept and move on. Give a Political Science major a B and they might have a heart attack. If Yale keeps harming the GPA of science majors with such stringent grade distributions, it will see a continual decline in science students. I for one am changing to a non-science major while still staying premed---I want the bare minimum of science.
The above poster sums it up. By and large science classes are graded much more stringently and are curved to a B-, which denotes "average". A consistently above average science student will have a very below average GPA and will likely have worked much harder for it. Rational students rightly avoid science and other harsh grading disciplines for this reason. I think many of these enrollment problems could be solved by curtailing grade inflation in other departments by implementing a curve, etc. but this will never happen.
From the posts above I am seriously (re)thinking my decision of being a MB&B major. It is saddening to hear that grading is that much more harsher in the sciences. This makes me really being to weigh my options.

West Campus to open new doors in University’s scientific research
yay for the sciences!