Hi everyone!
Apologies for being silent these past two months. Last Thanksgiving the children of a friend of mine asked to see my web site. I hesitated, knowing that I’ve geared this site entirely to adults. Relenting, they confirmed my fears by only taking interest in short video clips.
So I’ve been thinking about how to redo things. I’ve also been envisioning several other nature education programs not strictly related to spiders. Here’s the line-up of programs I’m planning:
- Spiders, microhabitat, and ecology
- Biophysics and biomathematics
- Nature appreciation and nature-inspired creativity
Although spiders will remain my primary critter of expertise, I’m going to branch out broadly beyond spiders. I’ll be revising the site with the following objectives in mind:
- The site will serve as a calling card for my childrens’ programs, including program descriptions and calendar of public events.
- The blog will serve as an endless virtual nature walk, giving kids sample tidbits from all of my programs.
- Captions and summaries will be written at a 3rd or 4th grade reading level.
- Articles will be written at a 5th or 6th grade reading level.
I fully expect everything to be interesting and educational to adults as well, but children will be my primary audience.
I have numerous projects underway right now, but I’ve already begun work on the revision. Thanks for hanging in there!
~joe
On Sunday NASA again delayed launching the shuttle Atlantis, claiming a problem with a fuel sensor guage. However, we have video that shows us what really happened that Sunday. Click on this photo:
A giant spider jumped onto the shuttle and proceeded to attack it. For a moment there it looked to me like it was gobbling the shuttle up. And it’s definitely a jumping spider (family Salticidae), probably in the genus Phidippus.
The other theory is that the spider was just walking on the camera lens, but we all know that would not have delayed the launch.
As reported in the Times Online and on Reuters India, Japanese scientists have made it possible to wear socks made of spider silk. More accurately, the socks are 10% spider silk protein and 90% silkworm silk protein. The trick was to inject genes from a spider into silkworm moth caterpillars, whose silk could then be used to make the socks. This is exactly what geneticist Masao Nakagaki did, though it took him ten years to do it. He used DNA from the golden orbweb spider Nephila clavata, which is found in Asia and is related to our Golden Orbweaver, Nephila clavipes.
Nephila clavata. Photo courtesy Micha L. Reiser
(Creative Commons Licensed)
Spider silk is apparently better suited for clothing than any substance out there. It’s more durable than even kevlar, making it good for those of us who have a habit of shooting ourselves in the feet. But to make the socks, we need a lot of silk. We can pack silkworm caterpillars together industrial-fashion to draw the necessary amount of silk, but spiders don’t usually get along so well. We’d have one giant factory-room brawl. And being forced into slavery, spiders might just bite back. We’d rather have silkworm moths make spider silk. So voilá!
Now wait a minute here. Don’t we already have perfectly functioning socks? Yes, but most of our socks are made of artificial materials. Neither the manufacturing process nor the resulting socks are very good for the environment. Silk, however, is perfectly natural.
Dr. Nakagaki next plans to increase the fraction of spider silk protein to 50%, and he hopes to have spider-silk socks in stores by 2010. You know the jokes are coming. Users at drudge.com had some great ones… “Can you run across the ceiling in them?”… “Spider Silk Socks—buy seven get one free.”
I can’t believe it’s December 7th and it’s 80 degrees Fahrenheit out there. For the record, I still have a Spinybacked Orbweaver (Gasteracantha cancriformis) out front in her web. I love the faces on their abdomens. This one has a French moustache:
Last week we had a night that seemed to dip below freezing. She spent the night hanging from a tattered web. In the morning I found her climbing very slowly up the web. She’s quite well today. I’ll be sad when they’re finally gone. Everybody in Austin has been enjoying the Spinybacks this year. They were everywhere.
Okay, just so you know, I’m stalling. I’ve spent the past few weeks working on another spider video. I’m really excited about this one, but sheesh! These videos are a lot of work!
On October 19th, at Lake Tawakoni State Park, I photographed two Guatemalan Long-jaws (Tetragnatha guatemalensis) at the center of rather large orb webs. I was thinking, “Aha! The spiders are making orb webs and not just monstrous sheets and tangles.” The next morning I got up early and spent hours watching several locations on Texas’ famous giant web.
I was trying to photograph regular orbweavers (family Araneidae) tearing down and eating their orb webs. Many nocturnal orbweavers do this in the morning. I did catch some of that, but I was disappointed when a female Furrow Spider (Larinioides cornutus) I’d been watching simply retired to her retreat without recycling her web.
Imagine my surprise when I came back to the web an hour and a half later and saw this:
That’s a female Guatemalan Long-jaw spider at the hub of the Furrow Spider’s orb web. This spider had taken over another spider’s web….
Even the cobweb weavers around the house are having Thanksgiving feasts. This one is on my front porch, and it has appropriately substituted a wolf spider for the turkey.
This is a reminder that those little cobweb weavers in the corners of the house can catch big critters too. The venom of many spiders only acts locally around the bite, but cobweb weaver venom contains a neurotoxin that attacks the entire nervous system. Anything caught in its web is fair game.
Actually, I took this photo on November 21st, the night before Turkey Day, just as the cold front was sweeping across Austin. Today the spider is hiding beneath an oak leaf that is suspended in the web (click on the image), waiting for the warm weather to return.
More big arachnological fossil news came yesterday, November 20th. In the Royal Society journal Biology Letters, Simon J. Braddy, Markus Poschmann, and O. Erik Tetlie reported having found an enormous fossil claw of a sea scorpion (order Eurypterida). The claw was 1.5 feet long, suggesting that the animal must have had a body 8 feet long. It’s the largest arthropod ever discovered.
The creature was a Jaekelopterus rhenaniae that lived about 390 million years ago in freshwater swamps and rivers. Ancient sea scorpions are thought to be the ancestors of modern arachnids. (That is, a species related to Jaekelopterus rhenaniae was likely the ancestor of spiders, not necessarily this species.)
It is not known how sea scorpions got so big. Early theories assumed that high levels of atmospheric oxygen enabled such growth, but large sea scorpions appear to have existed prior to high oxygen levels. A theory more in vogue is that competition from and predation by vertebrates may have made such large sizes infeasible in later ages. Arthropods are limited in size on land because the force of gravity would crush them under their own weight.
For more information, see the Biology Letters abstract, Science Daily, or Nature News.
Arachnid fossils have been making the news lately. On October 26th, the journal Zootaxa described scanning a fossil spider using “Very High Resolution X-Ray Computed Tomography.” This is the first time that the technique has been used to generate images of a fossil preserved in amber. The technique apparently improves on a technique previously only available at the University of Texas.
The spider is a new species of the family Micropholcommatidae, a group not found in North America. The authors of the paper, David Penney of the University of Manchester and others from Ghent University in Belgium, dubbed the species Cenotextricella simoni. The fossil is 53 million years old and was found in the Paris Basin region of France.
See the Zootaxa abstract or the stories at Science Daily and BBC News for more information.
