Wednesday, August 09, 2006

Teaching Biology...

...In the order it was discovered.

A little more than a year ago, at the Evolution 2005 meeting in Fairbanks, Alaska, I attended a talk describing the marks granted to a few American states (Ohio and Indiana, I think) by a science-education-advocacy organisation. The core message was that one state, Ohio, had recieved a very poor mark for teaching Evolutionary Biology, and the other, neighbouring state (I think Indiana, but I'm not sure) recieved a high mark. Potential reasons and some further observations and interviews carried out by a researcher were discussed.

After the talk, a question was raised in the audience about the suitability of teaching evolution in biology class before other components of biology, such as cellular anatomy or genetics. The underlying argument to the question was that evolutionary theory requires a strong foundation in the features of life, and that high school students should learn these other features first, then be introduced to evolution.

This discussion led me to thinking about the order the world, or history, learned of the various fields of biology. I think, and I intend to demonstrate here, that "we", i.e. humanity, learned about biology in the order evolution-first.

It has been widely argued that prior to Charles Darwin publishing On The Origin of Species, biology was just "stamp-collecting". The relevant quote is widely attributed to Lord Kelvin, a prominent physicist of the late 19th century. The idea is that the Theory of Evolution by Natural Selection provided a predictive, hypothesis-testing framework for investigations into biological phenomena. That the processes of life, and the science of Biology are subject to the laws of Physics and Chemistry became a respectible intellectual position, though it was probably not until Watson and Crick's famous discovery of the structure of DNA that this idea was really defensible.

I can think of an arbitrary number of fields or disciplines within the science of Biology. For the purposes of this post, I'm going to divide biology into 10 divisions, and try to pin down the date of the discovery that forms the foundation of each.

In alphabetical order:
Cellular Biology
Developmental Biology
Ethology (the study of behaviour)
Evolutionary Biology

Cellular biology is the study of processes within living cells, including the processing of DNA and RNA. Within the field of Genetics I include molecular biology, evolutionary genetics and genomics. Physiology includes all studies of the regulatory and between-tissues interactions of multicellular organisms, at all levels greater than individual or small numbers of cells. Obviously, there is quite a bit of overlap between these divsions; I am not trying to pigeon-hole any working scientists, and most biologists I know work in two or more of these fields.

This is my proposed timeline of discoveries. I first list the division, followed by the name of the founder and the date of publication of the key discovery or experiment.

Physiology (Harvey, 1628)
Taxonomy (Linnaeus, 1735)
Biochemistry (Payen, 1833)
Anatomy (Gray, 1858)
Evolutionary Biology (Darwin, 1859)
Cellular Biology (Schleiden & Schwann, 1839; Pasteur, 1861)
Ecology (Haekel, 1866)
Genetics (Mendel, 1866; de Vries, Correns, & von Tschermak-Seysenegg, 1900)
Ethology (Wheeler, 1902)
Developmental Biology (Thompson, 1917)

I got most of the above information from Wikipedia, so maybe you should trust it only as far as you trust Wikipedia.

Cellular biology is listed for 1861, rather than 1839, because it was Pasteur's experiments that really demonstrated the validity of cell theory. Genetics is listed for 1866, but after Ecology 1866 because Mendel's work, while published, was largely ignored until 1900.

Teaching biology in the above historical order seems somewhat foolish, actually. I was kind of hoping that my little exploration here would lead to a nice map of the order of teaching, but I will not actually be advocating (not right now, anyways) teaching Physiology before Anatomy, or jumping from Evolution to Cellular to Ecology.

Teaching biology under some sort of scale framework seems more pedagogically sound. I think it would be best to choose to work either from small-to-large or large-to-small, and thus put the divisions of biology in the order or reverse order:

Biochemistry (molecules, time scales on the order of microseconds to minutes)
Cellular Biology (cells)
Physiology (within individual organisms, time scales on the order of lifespans)
Anatomy (individuals)
Developmental Biology (individuals, time scales on the order of hours to months)
Ethology (small numbers of indivduals, time scales up to seasons)
Genetics (small-to-moderate numbers of individuals, time scales of generations)
Taxonomy (biodiversity and moderate numbers of species)
Ecology (many species, time scales up to 10 000 years)
Evolutionary Biology (large scales of time and space)

Anyway, this idea has been rattling around in my head since last summer. Commentary, as usual, is most welcome.

Selected references:
Wikipedia's History of Science page (contains under-supported sections and contradictions)
Wikipedia's History of Biology page
Wikipedia's Cell Theory page

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