Thursday, June 25, 2009

A Look at Biology from a Historical Perspective

In thinking of science for middle schoolers, physics, while very important hardly stands alone in the realm of science study. Yes, physics was shown to underlie all things in the end, but many advancement were made in other sciences prior to getting to the quantum level. The other two very important studies are biology and chemistry. Two additional subjects which also comprise some middle school science time are geology and earth sciences. All of these subjects are studied haphazardly in each of the middle school scope and sequences I was able to find on-line.

I have made it clear that presenting the evidence for each successive advancement in science is the proper way to teach science. A sure-fire way to make sure this happens in science is to study science historically. It is necessarily true that our current scientific understanding of the world was gained through hard-won evidence. Starting with the things that humans could see easily and then enhancing our conclusions through more subtle investigations through which learners then understand our current knowledge.

While I studied physics and chemistry (for engineers, of course) in college, my last exposure to biology was in high school. I've been reading up on it over the last few weeks. My reading began with Isaac Asimov's Guide to Science Volume 2: The Biological Sciences (1975). It's a good start to help understand which developments led to what results and a general timeline. The way the subjects are delineated leads to overlap too frequently to be a straight-forward guide for the historical developments.

At the most recent library booksale, I picked up Men, Microscopes, and Living Things by Katherine B. Shippen (1955). This is a book geared toward children. As a guess, I would imagine a middle schooler could easily read it to themselves. While the book does not go into enough detail for a student to recreate the actual steps of each discovery, it lays out the important steps quite well. Each chapter focuses on the important next step that allowed biological understanding to advance. It does not spend much time on medical advances (skipping Hippocrates completely and not discussing much medical history at all).

The book follows a historical path. It starts with Aristotle's for non-mystical understanding. Aristotle observed much in nature (unlike his physical science proclomations). After Aristotle, the author recognizes that scientific advancement effectively ground to a halt under Roman rule. It discusses some of the false information compiled by Pliny the Elder and the incredible tales of the Physiologus.

Herb gathering was an interesting advancement during the Middle Ages. It doesn't much count as science, but it was an important task that was made more difficult by superstition and blind reliance on authority. When new herbals were copied with accurate diagrams, the task of gathering plants for medicinal purposed was simplified.

The Rennaisance brought forth two of the largest contributors to the understanding of the human body, Andreas Vesalius and William Harvey. Vesalius was famous for his in-depth dissections and representations of human anatomy (many drawings of his text will be quite familiar). He did not rely on authority and his showing the reality of the human form ended with his resignation as the theologians were aghast that he would show man with an even number of ribs when everyone 'knew' that man had to be missing a rib as Adam's rib was taken to make Eve. William Harvey calculated the amount of blood pumped by the heart to show that the blood must move in a circular fashion through the body. He proved it through a number of other means as well. Harvey's discovery of circulation ends more happily as people readily adopted it. (From Asimov, it is stated that Harvey was the first to use math in looking at biology.)

Noted at this point is the proliferation of scientific ideas through societies devoted to it. The more people who were made aware of science advancements, the more people could discover knew knowledge instead of rediscovering for themselves the same things over and over. Also to aid in understanding, many societies started to collect items required for study, like biological specimens preserved in alcohol.

The next major advance was the microscope and the use of it by Malpighi to discover capillaries (laying to rest how blood was transferred from arteries to veins) and various other studies of animal anatomy, Swammerdam's immaculate dissection and reporting of insects, and Leeuwenhoek next level acheivements. Leeuwenhoek made such fine lenses for his microscopes that he was the first to see the little beasties we know as microbes. A good deal can be said of Leeuwenhoek's, who was of humble origins, acceptance into the Royal Society, the premier society for scientific information at the time.

It seems proper for the author to next talk of Carolus Linnaeus. With the large amount of information gathered so quickly, it was time to find a more abstract way of cataloguing the knowledge gained. Linnaeus had discovered a way to simplify some of the information already gathered. More information attained from Baron Georges Cuvier showed proof of extinction. With the ideas of Linnaeus, Lamarck included more than just plants in a classification. In developing his classification from least complex (little beasties) to most complex (humans), Lamarck hit upon the idea that species can change slowly and that more complex creatures can arise from the simpler.

Darwin, of course, was able to hit upon an idea of why certain traits might differentiate a creature with his idea that those animals with changes that are best fitted to their environment are more likely to survive. Over a long ages of time new species are formed while others die off (almost verbatim from the book).

Von Baer's work with embryos added more information and showed that the embryos of all animals were so similar that it was exceedingly difficult to differentiate them in their early stages from observation alone. His work left some questions that Schleiden and Schwann were able to address with their cell theory. The cell theory showed the basic operation of all life. The author then continues the narrative of the cell (with a mistake about Brownian motion).

Introducing Mendel at this point seems logical to me and that is what the author does. A chapter is devoted to discussing his ideas of Mendelian inheritance.

Continuing the thought process about new species initiated by Lamarck and Darwin, Hugo De Vries is introduced. He helped provide further evidence in favor of the gradual changes in animals. He demonstrated that mutations can account for complete changes in species. These changes would then be subject to Darwin's theory.

To wrap up the book, the discoveries of sperm mating with ova to create the next generation, chromosomes, inheritance experiments with fruit flies and subsequent mutations and mapping of traits to chromosomes. The book necessarily ends there since it was published in 1955, much too soon after the publication of DNA to expect it explained in a children's book.

Overall, I like the historical lay out. From the small amount I know of biology, the discoveries that were highlighted seemed to be of great importance. I really liked how the author emphasized the throwing off of superstition and the importance of incorporating facts from observation. I especially liked that the integration of the classification systems, the cellular theory, and genes were highlighted. The entire book is 183 pages long (the type is about 12 point with 1 1/2 spaces for each line, so a lot of white space on each page) in 18 chapters. There are few illustrations.

It seems like a great book to help understand what types of experiments to look at first and to consider how the discoveries changed the thinking of the time. Given the extensive amount of material covered, it is brief in it's treatment of each particular subject and, as I said before, summarizes the experiments but not in such a way to allow recreation without additional sources. I am also sure that many (not quite as important) steps were overlooked to allow the book to have a broad view.

I like the book a lot and feel that it had a good narrative story of the history of biology. I think it would be a great book for any other parent who is looking to teach real sciences to their children in a meaningful manner to start to research.


Deb said...

Kim, thanks SO much for writing this up! I'm going to print it out to look at when I have a quiet moment soon.

christinemm said...

Great post. Thanks for writing it.

I learned of Shippen through a book list book "Who Shall We Then Read" by Jan Bloom, a HS mother. She and other Charlotte Mason method HSers who use "living books" instead of textbooks recommend Shippen's books. Most if not all are out of print. She does not talk down to the child reader.

You are lucky to have found one of her books. I find them hard to find even at library sales.

I can't recall if you've discussed the Joy Hakim science books. All the sidebar comments are distracting to me.

Right now I'm writing up the summary of HS work my kids did in the last year. Comparing plans to reality. After that I'll map out the next year's plans. At these times I think of all the stuff I thought we'd do that is still not done...this time I'll try not to beat myself up about it...

Kim said...

I'm glad you liked it. It's a bit pitiful to admit that it took hours!

I liked Aristotle Leads the Way, not having read the others. I agree that the magazine formatting is very distracting and it cannot even be ignored.

I also feel that the book is so exhaustive that it is wonderful on the one hand and perhaps overwhelming on the other. I certainly learned a lot.

As I was reading it, I was even struck by the thought that this could very well be one of the "living books" I heard so much about!

I feel like I'm playing catch up all of the time. I'm constantly remembering that I was supposed to do some such thing but never got to it for various reasons. I used to think, 'Oh, I have time,' but now that time has slipped away.

The only thing to do is plan again!

Rajesh said...

Hi Kim,
What a wonderful post. I think I have done justice to your hours spent on this post by clicking on each and every link and enhancing my knowledge of biology along with history a great deal.

Thanks for writing it.

Kim said...

Hi Rajesh,

I hope I will be forgiven for using Wikipedia for the links. I am sure I could have found additional, possibly more educationally related information, but I did decide to limit the post in that way.

I am glad you enjoyed it! I'm researching more and hope to include additional information (and confirm this information) through other sources.