Farewell

This is a sign-off. The brutal experience of trying to use new methods as a novice, whilst working with hostile faculty has finally beaten me down.  As my teaching obligations officially finished with the end of semester, I've decided to call it quits on education for good, and so there won't be any more posts. Since I have been sharing my links with a few people, I won't take them down (and will probably add to them as more tips come in from the FIRSTIV listserv).  Feel free to send me more links if you have anything you think belongs here.


Bon Voyage!

Yes, I will get to this too..

Trees vs. ladders

Thinking Like A Biologist (on a good day)

More on this soon...

Thinking Like A Biologist

Using Diagnostic Questions to Help Students Reason With Biological Principles

Step 1: Read the graph, Step 2: Interpret the graph

Sometimes students are missing the basics.  Like, for instance, don't panic when you see a complicated graph, just start by figuring out what kind of data is presented, and how, and only then try to interpret the thing.

Interpreting graphs is such an integral part of the scientific life that we are barely even aware we are doing it - but students are just starting out, and are much more likely to be spooked if they do not immediately understand.  Some advice from Teaching Issues and Experiments in Ecology formalizes the most basic processes of graph interpretation as the unimaginatively titled "Step One-Step Two" method.

Enhancing Education from Carnegie Mellon

This site is so lovely.  It is from the Eberly Center for Teaching Excellence at Carnegie Mellon, which sounds very posh, and looks posh too (maybe it's because of the money).  Anyway, it's something of an eligible bachelor, because it not only has looks and money, but substance too.  For instance, if you're feeling panicky because you have a problem with your class, try their Solve a Teaching Problem section - identify your problem from a long list (let's say, the perennially popular 'Students can't write'), and they give you some suggestions on possible underlying reasons:

Students lack critical background skills.

Students lack discipline-specific writing skills.

Students have misconceptions about what writing involves.

Students are encountering linguistic and cultural obstacles to writing.

Students may be intimidated by writing and lack confidence in their abilities.

Students are unclear about certain parameters of the assignment or do not know how to meet them.

Each then links to a short explanation and several strategies for addressing the problem, such as

Make your expectations clear.
Create “scaffolded” writing assignments.
Model how you approach writing tasks.
Require drafts.
Use performance rubrics.
Emphasize purpose-focused writing.

Sigh.

More on genetics curricular revision - Down with Dominance

On a similar topic, some bloke called Douglas Allchin advocates for biology educators to do away with that nasty old concept of dominance (see, for instance, this old American Biology Teacher article).  I think he has some good points, if you ignore his worries about reinforcing 'dualities' and inflexbility in the arenas of conflict (I'm pretty sure there would still be wars and conflict even if we taught with co-dominant genetics examples instead of dominant ones - just saying.)

For instance, Allchin reminds us that many of the most prevalent misconceptions about genetics are actually misconceptions of dominance relationships:

"...some traits are inherently more likely to be inherited than
others; dominant traits are more prevalent in the population; adaptive traits eventually
become dominant through natural selection; mutations or "abnormal" genes are recessive;
dominant alleles subdue or control recessive ones...I trust these sound all too painfully
familiar"

If these don't sound painfully familiar, I suggest you immediately find the nearest Freshperson and grill them on what they know about trait dominance (don't worry, you don't have much to lose, they already think you're crazy).

Part of the problem is that the concept of dominance doesn't have much to do with inheritance, even though that is the context in which it is invariably taught.  Dominance relationships describe phenotypic expression and as such are as complex as the physiology and development of the organism they are applied to.  They cannot be neatly explained by any kind of 'universal genetic mechanism', in the way that Mendel's laws (of segregation and independent assortment) now can.  This problem is self-evident to anyone that has tried to explain the meaning of dominance to genetics newbies and had to resort to a random assortment (pun intended) of different examples to give a sense of the many different ways that dominance relationships can arise.  To make matters worse, the technical word 'dominant' has all kinds of non-technical connotations that invite misinterpretation.

Allchin's solution is to point out that students don't actually need the concept of dominance to understand inheritance.  His specific suggestions here were:

1) Re-frame genetics curricula by starting with co-dominant examples as the 'default' type of inheritance (which at the very least would be democratic, since dominant traits are by far the minority.)
2) Use the kind of co-dominant notation used for blood-types.
3) Teach patterns of phenotypic inheritance as part of development instead of inheritance.  (I got the feeling that he meant 'molecular genetics' when he said 'development', but maybe that's because where I think it should go).

I definitely agree that genetics should start with co-dominance and incomplete dominance.  You can certainly first explore Mendel's laws with such examples without muddying the terrain with traits 'dominating' each other, and the idea neatly does away with the textbook fiction that these cases demonstrate 'non-Mendelian' inheritance.  The only truly non-Mendelian inheritance I'm aware of is organellar and epigenetic inheritance, and those topics are rarely explored in introductory classes.

Upside-down Genetics Curriculum

I feel like a really sensible idea was proposed about genetics curricula in the American Journal of Human Genetics last year.  Michael Dougherty points out that the genetics unit of freshman biology typically uses a historical narrative: Mendel noticed that something weird was going on with his peas, proposed the existence of a genetic unit, these genetic units helped analyse pedigrees and crosses, genetic units segregate on chromosomes during meiosis, genetic units are made of DNA, then molecular genetics was finally understood and all was right with the world, hurrah!

Dougherty's idea is that framing genetics in this way and focusing almost exclusively on Mendelian disorders makes the introduction of complex, quantitative traits at the end of the module seem token; just an afterthought, rather than the real prize.  He suggests that this can only fuel the naïve genetic determinism that is prevalent among the public.  What we could do instead is to start with what students already know or can easily observe - variation in phenotypes and an incomplete tendency for phenotypes to be inherited - then build the gene concept up from that basis.  For instance, students would learn about additive polygenic inheritance and the influence of environmental factors before they learned about Mendel and Punnett squares.  For some reason this makes perfect sense to me, and I can't figure out why we haven't always done it that way!