Published on March 24th, 2013 | by James Ayre31
Angolan Witch Spider, Giant Spider Found In Texas Is A Hoax…
There have been rumors circulating on the Internet of a spider large enough to eat people’s dogs and cats… While it should be obvious that such an animal would not be discovered out of the blue, and the poorly done photoshop job should be a hint, apparently many people have fallen for this. So I figured why not do a debunking and talk about something that I love, spiders.
To start with the photo, there are VERY clear signs that it was photoshopped, and poorly at that. And even if the photoshop had resulted in a masterpiece of deception, the image simply doesn’t make sense; the shape, body type, location, behavior, none of it.
More interesting than any of that though, is that there are real limits to how large spiders can actually get, based primarily on the (relative) ineffectiveness of their “lungs”, among other factors. They simply can’t grow past a certain size in relation to the oxygen content in the atmosphere, or they wouldn’t survive.
Most spiders possess what are called “book lungs“, which are completely unrelated to what we normally call lungs, and developed independently. And from fossil evidence, we can determine that these structures have remained more or less unchanged throughout the past 400 million years because of how effective they are. There are downsides/limits to them though, with relation to lungs as we know them. As body size increases in relation to gas molecule size, they become less effective. This means that as animals with these structures get bigger they become less and less effective at “breathing”, which places limits on their maximum size.
Other limits to their maximum body size include a decreasing effectiveness and durability of their exoskeleton and muscular system, as they get larger they generally need to become thicker to compensate for this (especially highly-mobile spiders), tarantulas are a good example of this.
The two largest spiders alive in the world today are both approaching the limits of maximum spider size, in the current atmosphere anyways, perhaps not in the distant past. They are the foot long Goliath bird-eater tarantula, and the Giant Huntsman in Vietnam. Neither of these come close to approaching the size of the “Angolan Witch Spider”.
The largest known prehistoric spider species is the Nephila jurassica, which was smaller than many modern species. With how rare spider fossils are though, it is very possible that there were much larger species. A couple of years back a giant “spider” fossil was discovered that was the size of a small dog and dated back to 300 million years ago, but after deeper investigation the fossil species has now been labeled as a species of “water scorpion”, not a spider at all.
All of this isn’t to say that there aren’t undiscovered spider species, even strange ones, as new spider species are discovered all the time, such as the species Cerbalus aravensis. But as anyone with an even somewhat discerning eye can see, the Angolan Witch Spider is clearly a hoax… Though to be fair, the unicorn was a real animal…
Image Credit: Screen Capture; Goliath Bird-Eater via Wikimedia Commons