Comments on: Friendly Neighborhood Spiderman

By: Steve Reuland

Steve Reuland — Wed, 26 Oct 2005 19:16:36 +0000

"Still, I have always been willing to catch even big wolf spiders under a glass, then slide a piece of paper beneath it, and throw them outside. I hope the arachnidae appreciate that." They probably don't. One thing I was surprised to learn from Rob Crawford's Spider Myths site is that you've got your indoor species, and your outdoor species, and very few that are both. In other words, the spiders you find in your house didn't come wandering in from outside; they live their entire lifecycle indoors and are not well adapted to survive outdoors. You do them no favors by kicking them out of their home. (He also points out that what you think are wolf spiders are almost certainly European house spiders, not related to actual wolf spiders.) One thing Crawford takes great pains to explain is that nearly every species of spider is competely harmless; they don't do any of the things that they're accused of doing, like biting people in their sleep. Spiders live in your house for one simple reason: insects live there. The latter are almost always going to pose more of a threat to your health and happiness than the spiders, who are just trying to make a living by violently killing and eating those insects. Humans aren't on the menu. We're too big.

By: nnyhav

nnyhav — Wed, 26 Oct 2005 12:49:14 +0000

His logic is simple: find characteristics of spiders’ shapes that independently select the same exact group of organisms. “There are about 1.75 million species on this planet,” Dr. Platnick explained. “Select from these all the organisms with abdominal spinnerets to produce silk – about 38,000 species. Repeat this process and select all organisms with modified male pedipalps for copulation. You end up with the same 38,000.”
This congruence of characteristics unites spiders uniquely from all others, he said. Apply the concept with higher degrees of specificity, and species’ characteristics emerge.
“You start with the null hypothesis that they are all the same. It doesn’t take long to see that they are not,” he said. “Then you divide them into groups of specimens more closely related to each other.”
As he explained the process, Dr. Platnick dug out a paper describing a new species he had identified in Australia. “The differences here are in the male sex organs, or their pedipalps,” he explained. Carefully drawn in profile, one pedipalp had subtly different arrangements of sub-millimeter-sized bulbous growths.

A lepidopteric strand to this web of sense: Nabokov’s taxonomic organisation of the Neotropical Blues based on genital configuration has held up and been cladistically confirmed (cf Kurt Johnson)—cited as anticipatory though not predictive of resolution to speciation problems (and you were expecting maybe reference to Invitation to a Beheading?)

But it all goes back to Thoreau.

By: Kenny Easwaran

Kenny Easwaran — Wed, 26 Oct 2005 06:22:11 +0000

Actually, it’s not just the snakes and spiders and ticks and jellyfish. Even the mammals are poisonous. That is, the platypus has poisonous spines on its back legs. I hear they don’t kill you, but just cause excruciating pain for several months.

By: Thompsaj

Thompsaj — Wed, 26 Oct 2005 01:38:16 +0000

Here in South Carolina, some call them “banana spiders” though I’m not sure why

By: belle waring

belle waring — Wed, 26 Oct 2005 01:06:49 +0000

mrs. tilton: oooog, those are the ones. the bodies are smaller than tarantulas, granted, but the “wing-span”, so to speak…in short, ooooog.

By: Fred the Fourth

Fred the Fourth — Tue, 25 Oct 2005 22:00:40 +0000

A few years ago my wife and I were planning a dive trip to the Barrier Reef and Coral Sea, along with side trips to the outback and northeastern rainforest. Handily, the very next copy of Scuba Diver mag that showed up had a listing of “World’s Deadliest Sea Creatures” or some such. Leafing through it, I couldn’t help but notice that essentially all of them were fond of that little corner of the world. Blue rings, Box jellies, various seasnakes, Bull sharks, Saltwater crocs, and on and on.
In the event, we saw lots of sea snakes (especially on the Yongala wreck, where they are quite…friendly, like kittens). Didn’t have any problems with any of them. Actually, the cool thing about those sea snakes is that they are air-breathers, living on a wreck at 90 feet. So they can’t really hide, and you get to … interact with them..Yeah, that’s the word.

By: urizon

urizon — Tue, 25 Oct 2005 21:46:38 +0000

“This is a very fun NYT Science Times article about one Norman I. Platnick, who has ‘discovered more than 1,200 new spider species, several dozen new genuses and a couple of new families.’”

And they were all living under my bed.

By: The Sixth International

The Sixth International — Tue, 25 Oct 2005 21:00:15 +0000

Small Americans

Even though spiders creep Belle Waring out, she’s game enough to link to an article about Norm Platnick, doyen of spider systematics. Platnick is a BSD of the systematics world, and has had the honour of being savaged by Richard Dawkins for being an i…

By: Alan

Alan — Tue, 25 Oct 2005 20:46:16 +0000

Belle, the blue ring octopus will fit easily in the palm of your hand.

Kieran, the snakes are mostly quite timid. You can pin them to the ground with a forked stick and grab them behind the head so they can’t bite, but they usually flee before you get the chance. Except for the taipan. Don’t try this with a taipan.

And for the benefit of non-Aussies here, drop bears are fictional. Paralysis ticks, alas, are not.

Apart from crocs and sharks, all the deadlies really are small enough to pick up. If you stay on dry land, you will not be eaten and excreted.

By: John Quiggin

John Quiggin — Tue, 25 Oct 2005 20:08:00 +0000

No mention yet of sharks (as with spiders, the crocs keep them down in tropical parts), paralysing ticks and drop bears.

By: Jeremy Osner

Jeremy Osner — Tue, 25 Oct 2005 19:30:02 +0000

Heh—I saw ‘specie’ for the first time when I was reading a Melville pirate story (Benito Cereno) this summer, and had to look it up.

By: phil

phil — Tue, 25 Oct 2005 17:47:09 +0000

“Species” is indeed its own plural. I never forgave my grade-school English teacher who tried to fob “specie” off on us on one occasion. (And he wasn’t discussing monetary policy.)

By: jet

jet — Tue, 25 Oct 2005 16:50:48 +0000

Don't forget the fark'n jellyfish:

The stinging process of the nematocyte resembles a jack-in-the-box mechanism....This pressurized process has a high internal hydrostatic pressure of 150 atm that causes the ejection to occur within 3 milliseconds, with an acceleration power of 40,000g and a force of penetration of 20-33 kPa. In addition, the nematocyst is capable of penetrating up to a depth of 0.9 mm. This depth deposits the toxin into the microvasculature of the dermal tissue to be absorbed into the systemic circulation and anchors the tentacles to the prey.

By: Jeremy Osner

Jeremy Osner — Tue, 25 Oct 2005 16:19:05 +0000

Mr. Margolies—is “species” its own plural? Always wondered.

By: David Margolies

David Margolies — Tue, 25 Oct 2005 15:53:09 +0000

Spelling flame:

“several dozen new genuses…”

‘genera’