01 August 2014

The Passionate Observer and The Life of the Spider

In the flower bed next to our front stoop, between a boxwood and a hooked pole with a bird feeder, is a perfectly-woven, silky orb web. The web is horizontal to the ground, and describes a logarithmic spiral. Clinging to the bottom of it with her four long front legs and her four shorter back legs is a beautiful spider. She is vivid green with little black bands along her legs. Her pill-shaped abdomen is streaked on top with silver blotches, and, as she has grown, bright yellow-gold markings on the underside of her abdomen have become visible as well. I saw a gentleman caller on her web one day, a smaller, darker fellow: brown with red markings. I didn't see him later that day, which makes me think that he mated successfully and hit the road. That means an egg sac is probably on the way filled with little baby spiders. Had the  male been unsuccessful, he probably would have still been hanging around as a snack. The internet tells me that the spider's name is Leucauge Venusta, which is an ugly name for such a pretty spider, or the "orchard orbweaver" which seems to fit better.


Jean-Henri Fabre
If I had seen her there last summer, I most likely would have taken a broom to her web and smashed her underfoot, rather than carefully checking in on her every morning as I water the garden. Ah but that was before Jean-Henri Fabre. For science each year my wife reads through books of nature study with our kids. They've enjoyed Ernest Thomas Seton and Edwin Way Teale in the past. This year, my wife discovered Fabre. Jean-Henri Fabre was a French entomologist (and physicist and professor) who lived from 1823-1915. He was a admired by Charles Darwin who called him "an inimitable observer", and is considered to be the father of modern entomology. He was known mainly for his studies in and experiments with instinct behavior in insects. He amassed an enormous collection of notes and observations which were published under the title Souvenirs Entomologiques, which have been divided up and translated into numerous books in English.

The book that my wife read to the children, The Passionate Observer,  is a selection of Fabre's writings accompanied by lavish watercolor illustrations by artist Marlene McLoughlin. Fabre is perfectly suited for reading out loud to children because, while being imminently scientific and detailed, he eschewed scientific jargon that obscured rather than revealed meaning. He wrote, "My conviction is that we can say things without using a barbarous vocabulary: lucidity is the sovereign politeness of the visitor. I do my best to achieve it." Based on the strong recommendation of my kids, I sat down and read The Passionate Observer and loved it. It is only a smattering of Fabre's writings, covering such creatures as Halicti (a type of bee) Grasshoppers, and Cicadas. He lovingly describes the appearance and behavior of each creature and presents his observations, freely drawing on autobiographical material to keep the reader's interest. It's a great introduction to Fabre and a short book, only 133 pages, so it's a quick read.

After that brief foray into Fabre, I was left wanting more, and so I turned to a longer book with a specific focus: The Life of the Spider. In this book, Fabre primarily explores two types of spiders, Lycosa spiders or "wolf spiders" and Epeira spiders. The book begins with Fabre's experiences with one type of Lycosa, the black-bellied tarantula. I learned that this spider Lycosa Tarantula is the true bearer of the name " tarantula". The spider Americans call a tarantula is actually a member of the family Theraphosidae. After discussing the tarantula, Fabre introduces the Epeira, a family that includes many garden spiders and orbweavers. He then spends five chapters going into more detail about the life and instincts of the Lycosa and then six chapters on the life of the Epeira. Along the way he gives nods to a few other types of spiders as well: the crab spider, the labyrinth spider and the clotho spider.

The book ends with an appendix about the geometry of the Epeira's web, which is a bit more theoretical than the other parts of the book. You see, even though Darwin was a great admirer of Fabre, and the two carried on a correspondence with one another, Fabre was never convinced by Darwin's theories of random mutation and natural selection. In the appendix, Fabre details the amazing geometrical features of the Epeira's web and how the same features are found in other parts of nature. He discusses how though evolution may explain the logarithmic spiral of a snail's shell, it does not explain the logarithmic spiral of an Epeira web, which requires a particular action by the spider that is not tied to any particular physical characteristic. Clearly this instinct is not based on physical mutation but is a special kind of knowledge implanted in the spider which is only activated at a certain point in its life cycle.

After reading these two books, I've been spending a lot more time looking at the ground and at bushes. Fabre sparked a wonder in the natural world that I haven't felt since I was a kid, and that's something we can all use more of. Many of his books are available for free on the internet, so go and learn about the world of insects with the inimitable observer himself! Meanwhile I'll keep observing my Leucauge Venusta and the Pisaurina Mira family living in the bush near our mailbox.

2 comments:

Mom said...

Spiders indeed! Just make sure you don't bring any up here when ya'll come to visit! I'd rather have a snake in my house than a spider! Love ya buddy

mom said...

I'm reading your blog on my phone!