Day: November 26, 2011

Saturday, 26 November 2011

09:37 – Barbara is due back tomorrow afternoon, so tonight’s my last chance for wild women and parties. No luck so far.

I’m still working on the chapter on fungi and lichens. I’d forgotten how much I hate biological taxonomy. When Barbara and I were taking biology classes in junior high school, fungi were still classified as plants. Then in 1969 Whittaker proposed the five-kingdom system that put fungi in their own kingdom, which they richly deserved. For the next 20 years, everything went swimmingly well, until DNA analysis pretty much wiped out morphology-based taxonomies, which really messed everything up.

Imagine you had to classify four people under the old morphological taxonomy. Individuals A & B appear Nordic–very light skin, blond hair, blue eyes. Individuals C & D appear sub-Saharan African–very dark skin, brown hair, and brown eyes. Under the obsolete morphology-based taxonomy, individuals A & B clearly belong together, as do individuals C & D. But then DNA analysis comes into play, showing that individuals A & D are more closely related to each other than either is to either B or C, and that individuals B & C are more closely related to each other than either is to either A or D. So, in the new DNA-based taxonomy, individuals A & D are in one group, while individuals B & C are in another group. It makes sense scientifically, but it is non-intuitive to say the least. (Obviously, all four of these individuals are actually members of the same species and subspecies, but the point remains.)

In a more accurate example, fungi have always been considered more closely related to plants than to animals. In fact, most biology books, including recent ones, treat mycology as a sub-discipline of botany. But the reality, based on DNA analysis, is that fungi are much more closely related to animals than they are to plants. Geez.

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