Nasty

Parasite Rex: Inside the Bizarre World of Nature’s Most Dangerous Creatures, by Carl Zimmer.

I can’t remember who recommended this book to me, and I’m sorry about that. It may have been here or on Twitter. I thank you, who ever did so.

The subtitle here is not hyperbolic. These are some of the grossest and deadliest lifeforms on the planet, which infect hundreds of millions of humans, not to mention billions of other life forms. Indeed, who needs alien invaders when we’ve got parasitic amoebae, nematodes, flukes, fungi, insects, worms…? Actually, most forms of life are parasitic, and I am not speaking metaphorically. And so the history of life on Earth, evolution, is very much wrapped up in the relationships between parasites and hosts, driven and dominated by it. This story makes for fascinating reading, albeit sometimes rather stomach-turningly so. Not for nothing did Darwin despair of belief in a God who could create so many bringers of ghastly, violent death, to tiny insects and humans alike. A small subset of this struggle can be seen with sufferers of colitis and Crohn’s disease, in which people’s own immune systems attack the lining of their intestines. Because the diseases spreads with development (and the eradication of intestinal worms), it’s thought that the human immune system, the end result (but of course not the terminus) of millions of years battling parasites, goes haywire when it doesn’t have to wrestle with worms anymore.

I’ll sum up with two words: creepy, amazing.

Inevitably, I have posted a few times on parasites. Here are two of these posts:

The Liver Fluke, which needs snails, bovines, and ants it drives to suicide.

Parasitic wasps take out caterpillars in the Back 40.