The Press today carries one of the periodic complaints that not enough people are studying science, and that this endangers our future as a "knowledge economy". Unfortunately, while it dutifully quotes scientists and educators about how this is a Bad Thing, little effort is made to analyse the underlying problem. Which is a shame, because the underlying problem is very simple: it's the jobs, stupid. There aren't any, or at least not enough to make it worth the risk of studying to get one.
Science is not like other careers. If you want to go into business, you go to university and get a BCom. If you want to work in McDonald's, you get a BA. But if you want to work in the sciences, a Bachelor's degree is not enough - you need to get a PhD to even get a foot in the door. This means spending seven to ten years of your life learning everything about nothing to have any hope of getting a job. If you stop early, your career prospects are limited - if you did biology, you can work as a lab technician, and get paid slightly more than the minimum wage to do mindlessly repetitive and intellectually unrewarding work that is beneath even robots. Anything else, and you're limited to teaching (which some people would say is much the same).
Unfortunately, if you study for those seven to ten years to churn out five copies (hardbound) of your thoughts on "sexual behaviour in the lesser spotted weka: an integrated computer model", you are likely to find that there is no position for you at the end of it. There's a limited number of places in our universities, and they're all full. Our CRIs (who used to be so short of PhDs that they'd send people overseas to get them) have been shedding staff for over a decade. And the private sector simply isn't interested in R&D - that would be investment, anathema to the short-term, strip the assets, screw the shareholders, and relocate to Singapore thinking so beloved of our managerial class. As a result, twenty to thirty percent of our science graduates are leaving the country. Which sends a very clear message to those at the start of their university careers considering a career in science: that there isn't one. Better to do computer science instead; you'll probably make more money that way anyway.
Before anyone gets the wrong idea, this doesn't mean that there isn't a problem. There's no jobs now, but there will probably be plenty in a decade, when universities and CRIs face block retirements among the few staff who survived the perpetual restructuring of the 90's. But students respond to the signals the market is sending now, and they're all pointing in the wrong direction.
As for solving it, politicians and business leaders need to move past the rhetoric of "science is vital for our future", and actually put their money where their mouth is and ensure that there are jobs at the end of the process (or, in simpler terms, hire more fucking scientists). Otherwise, when they can't find an expert in quantum analysis of sheep intestinal parasites in a decade's time, they'll have no-one to blame but themselves.