What this means is that if a spider were of enormous size, then its physiology would have to be considerably different than spiders as we know them now. Their breathing system would have to function differently, and there may well need to be some element of skeletal support to replace/supplement their exoskelton. In order to see such changes there would have to be some major changes in the spider's DNA. But what are the chances that someone would go messing around with the spider gene pool? Well.....
Spider Goat Reality Check: Truth is stranger than fiction
In 2000, a Canadian company began breeding goats that had been modified with orb weaver spider DNA. If you're like me, this sounds unbelievable. Here's some coverage from the BBC, The New York Times, and an informative video produced by VCU.
The rationale behind the project was based around the incredible range of potential uses for spider silk . From Lawrence Osbourne's NY Times piece:
Nexia foresees tapping into the $500 million market for fishing materials as well as the $1.6 billion market for industrial fibers in the near future. And the haute-couture world is already intrigued by a nearly weightless gossamer-like fabric. But the real gold mine might be body armor: the Pentagon is working with Nexia to develop a prototype of a new kind of vest that might be made entirely out of goat silk. The vest would be only a little thicker than nylon, but it could stop a bullet dead.
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In any case, the properties of spider silk have long been recognized. Fishermen in India have always prized it for the making of their nets; American Civil War soldiers frequently used it as a surgical dressing. The problem lay always in getting sufficient quantities of it. Whereas silkworms are peaceful herbivores and can easily be farmed, spiders are aggressive territorial carnivores that need plenty of space and solitude. In farm conditions, they moodily attack and eat each other.
The solution to this problem was to find a way to create an animal that had the ease of husbandry and the silk production of spiders. Enter Prof. Randy Lewis of the University of Wyoming. He lead the team that spliced spider genes into goat embryos that were then cloned to make two kids. These goats were then bred, passing the added spider genetics down their bloodline. Nexia worked with a number of breeds, with the total number topping out around 500. There is a good summary interview with Randy Lewis here .
However, Nexia ran out of cash, and by 2005 hundreds of spider goats had been euthanized. The few dozen that remained were transported to another Canadian farm, where they were eventually picked up by Lewis, and brought back to Wyoming. They are there still, and the research continues. In January of 2011, David Pogue's “Making Stuff Stronger” program for the PBS series Nova spent some time at the facility and gives a very good explanation of the process (at the end of this episode, if you're curious).
Prof. Lewis and his team are doing good science and have really intriguing ideas. Although it's certainly startling to hear about a spider goat, it's important to keep in mind that it's only 1/70,000th spider. If you want to describe the process in a more palatable way, consider that spider silk is 100% protein, and goats' milk is filled with different proteins. These goats have just been tweaked to allow this one additional protein into their milk.
So if you've read this little article and if you still find the J'ba Fofi ridiculous, if you laugh at the unbelievable things that some people claim to have seen, then imagine siting down with a member of the Baka tribe, and explaining that in the middle of the United States, there are goats which are part spider casually living out their lives, running around on a farm munching on plants. And maybe, just maybe, those plants might also be part spider. Don't believe me on that one? Check out the University of Wyoming's patent application.
Pleasant dreams, kids.