Life Scientists vs. Test Takers

Back in July, Physics Today ran an article on Reinventing physics for life-sciences majors (I couldn’t find an un-paywalled version, but this arxiv preprint seems to be close to it). As I’ve had some bad experiences with that class, I flagged it as something to read, but only got around to it last night. The main idea is that a “Physics for Life Sciences” course needs to be arranged around the way biologists think, which is fundamentally different than the way physicists think:

In general, physicists stress reasoning from a few fundamental principles—usually mathematically formulated—and seek to build understanding from the simplest possible models. They view the world quantitatively and pay much attention to constraints, such as conservation laws, that hold regardless of a system’s internal details. Biologists, on the other hand, focus on real examples and emphasize structure–function relationships; they rarely stress quantitative reasoning. The systems they deal with are almost always highly complex, with many interacting parts that lead to emergent phenomena. Biologists recognize that their discipline is subject to the historical constraint that natural selection can only act on pre-existing molecules, cells, and organisms, so their reasoning often depends more strongly on what exists than on “fundamental” abstract principles or simplified pictures.

Because of their focus on real systems, some of the biologists we spoke with considered traditional
toy-model physics examples—even such central and powerful ones as the mass on an ideal spring— to be irrelevant, uninteresting, and useless until physicists were able to show their value as starting-
point models for relevant, real-world biological examples. To do so required making it clear from the
first that a Hooke’s-law oscillator is an oversimplified model, then illustrating how the model would
be modified for realistic cases.

That sounds great, and some of the suggestions they make for curricular reform sound interesting. I have two problems with it, though. The first is just that going too far in the direction of shaping the course around how biologists think seems counter to the whole purpose of having people take courses on physics from physicists. After all, exposing students to the way physicists think is kind of the whole point– they should be exposed to methods that make (most of) them a little uncomfortable, and ways of thinking about problems that are fundamentally different.

I don’t think the authors would disagree all that much– their main goal seems to be wrapping some physics-y processes in biologist-friendly packaging, to make the unfamiliar thought processes more palatable. But this is the kind of idea that can easily be taken too far, re-shaping things to a degree where it doesn’t actually provide any benefit in terms of exposure to other modes, so I would recommend a bit of caution here.

The other objection is more practical, and may have to do with the fact that they may be seeing a different population of students than we see. Because while I think their course sounds great from the standpoint of presenting relevant physics in a package that will benefit research biologists, that’s not the problem we have. The negative experiences I’ve had with students in the life-science course are less the sort of thing that comes from biology-style thinking and more the problem Thoreau describes, namely that “Pre-meds are more helpless than a marsupial infant in the pouch.”

Our “Physics for Life Sciences” course isn’t generally populated by students who are going to go on to graduate research in biology (those students are slightly more likely to take the engineering sequence, of all things). It’s full of students who think they’re going to be doctors, and are taking the course for two reasons: 1) because medical schools require it, and 2) because there’s a physics section on the MCAT. They don’t hate the class because they don’t see the relevance to biological research, they hate it because we don’t just give them a set of simple algorithms that tell them the exact steps they need to follow to solve the problems that will be on the MCAT. It’s not an exercise in interdisciplinary exchange for them, it’s a test-prep course.

Given that, I find some of the recommendations a little hard to imagine putting into practice. The call for more realistic situations and context-rich problems, for example, seems like a recipe for disaster. Whenever I’ve attempted anything in the life-science class that involved any ambiguity or need for individual judgement, the process has been infuriating for everyone involved. “Discovery” style labs without cookbook lists of instructions have been an absolute catastrophe.

Now, it may be that this stems from the fact that we’ve always used curricula that more or less follow the engineering format with a bit less math, the approach which the authors of the Physics Today piece disparage. It’s conceivable that a more truly bio-centric approach would bring the attitude around a bit. But that sounds like a whole lot of work and a huge risk, given that what our life-science students say they want (both in comments on course evaluations and through their actions in class and in lab) is in almost exactly the opposite direction.

It seems to work for the authors of that piece, though, so maybe it’s worth thinking about. They have another preprint describing Maryland’s program in considerably more detail, if you’d like to know more. Personally, though, I’m inclined to continue to avoid that course to the greatest degree possible…

Comments

  1. #1 Eric Lund
    October 16, 2013

    The negative experiences I’ve had with students in the life-science course are less the sort of thing that comes from biology-style thinking and more the problem Thoreau describes, namely that “Pre-meds are more helpless than a marsupial infant in the pouch.”

    That was my experience the term I TA’ed the equivalent course at my graduate alma mater. I don’t have any data regarding which sequence the grad school bound biology majors took, but I do know that many of the students in that course were from that feared and dreaded population, the would-be pre-meds. Did I mention that pre-meds are dreaded and feared among physics instructors?

    Maybe it really is a different population at state universities, with a larger fraction of biology majors actually pursuing that major for its own sake rather than defaulting into it as pre-meds. I don’t have statistics on that, either.

  2. #2 alex p
    October 16, 2013

    I heard this during one of those physics for bio courses:
    Pre-med student: “Why do I have to take physics to get into med school?”
    Professor: “So students like you don’t become doctors.”

  3. #3 Throeau
    October 16, 2013

    Thanks for the link, Chad.

    I think you make an important point about how the pre-med objection concerns test prep, not relevance. From what I hear, they can be similarly annoying in biology classes. Maybe not to the same extent as in physics, but it’s there. If we revamped the course to focus entirely on biology-rich contexts, they’d still be upset over the lack of hand-holding, sample tests, study guides to accompany the sample tests, etc. They definitely act like that in organic chemistry, never mind that organic chemistry is a foundation of biochemistry, i.e. the relevance ought to be blindingly obvious.

    Besides, doesn’t your school use Matter and Interactions in the engineering physics course? That’s a curriculum that’s more relevant to biology than your typical blocks-on-inclined-planes intro physics, focusing a lot on the atomic world. A student who does well in M&I ought to have an edge in certain areas of chemistry. And if you teach VPython like many M&I courses do, that’s a valuable skill for bioinformatics.

    In short, pre-meds would be pre-meds even in a class that’s 100% biology-focused.

  4. #4 M Harris
    October 16, 2013

    Ah yes, pre-meds. I entered university thinking I might want to study chemistry, so I took a special section of organic chemistry for freshmen only. Big mistake: 95% of my classmates were pre-med, and while some of them were nice people (and a couple, in fact, went on to become very good doctors), most were extremely test-oriented, and a substantial number were actively trying to screw everyone else over. For example, one classmate deliberately gave me a wrong answer during a study session, and another followed me into the dorm bathroom to try to psych me out the morning before an exam.

    Needless to say, I switched to physics straight afterwards and never took a chem or bio course again, but my experience does seem to have been atypically bad. A couple years later I got to chatting with my former organic chem lecturer at a joint chem-physics colloquium, and he told me that my class had been the most insanely competitive he’d ever taught. So maybe pre-meds aren’t always that bad.

  5. #5 Thoreau
    October 16, 2013

    I love that I managed to misspell my screen name while complaining about Kids These Days.

  6. #6 Beth
    October 16, 2013

    I hadn’t heard the marsupial comparison before. It made me laugh very hard, and I have seen it to be true. When I TA’d general chemistry, pre-meds were the worst. For a group of people so worried about self and how dear self measured up against everyone else, they could hardly reason their way out of a paper bag unless you’d already shown them how.

  7. #7 Thoreau
    www.highclearing.com
    October 16, 2013

    What gets me about pre-meds is that this phenomenon persists across many types of institutions. It’s common in both academia and the blogosphere to try to relate things to class, privilege, and disadvantage, but this pre-med issue seems to transcend those factors. I was a scholarship student at a private school full of rich kids, and my pre-med classmates in chemistry were like this. I now teach at a state university with (mostly) less privileged kids, and I see this same phenomenon. I see it in white and Asian kids. I see it in under-represented ethnic groups. I see it in men. I see it in women. My colleagues at a wide range of institutions report similar things.

    No matter how much or how little social capital a college student has, as soon as they decide to pursue a health profession they lose their ability to reason their way out of a paper bag, as Beth put it.

    I pity med school faculty.

  8. #8 EscapedWestOfTheBigMuddy
    October 17, 2013

    I struggling to teach physics to a bunch of pre-meds (and “pre-professional” as they say around here which seems to mean “planning to be a dental assistant or a pharmacy tech”) in my first year as a full time teacher. I notice that they don’t like the “fundamental principles and things you can do with them” approach (the smarter ones have even been able to articulate that, and I’m not worried about them: they can be my doctor or dental assistant or whatever where they grow up).

    But I really am looking for things I can do better. Will more examples from biological systems help? If so I have some reading to do, but I’m willing to do it.

  9. […] professors, biology professors, chemistry professors, and even English and history professors.  As Chad Orzel argued, the problem is not that they consider physics irrelevant to biology, it’s that they want […]

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