OK… there I was, minding my own business, browsing through the Boxing Day edition of the New York Times, if you will… when all of a sudden, my eyes fell on this little article…
Tiniest of Spiders Are Loaded With Brains!
(Nephila clavipes… one bright little bug!)
I ask you… how could I NOT read that right away??
And what makes these little bugs [1] so brainy?
Well, small spiders such as the Golden Silk Spider [aka Banana Spider, aka Golden Silk Orbweaver (Nephila clavipes)] and other much tinier spiders in the genus Mysmena have huge brains. In fact, they have brains SO big… they actually spread out into other parts of the spider’s body, filling up not only the body cavity but also spilling out into their legs!
(Do you love me for my legs or my brains? Why choose!?)
As the Times article observes, while the smallest had smaller brains in absolute terms, relatively speaking their brains were enormous. In other words, the smaller the spider the bigger the brain.
“The basic trend was that the smaller the spider, the relatively larger its brain is,” said William Eberhard, a biologist at the Smithsonian Tropical Research Institute in Costa Rica and an author of the study, which appears in the journal Arthropod Structure & Development.
OK… so they’re smart. What’s the advantage?
(Do I look like the smart type?)
Well… since the smallest spiders make a major investment in brain size, they are able to build the same kinds of complex webs as larger spiders, Dr. Eberhard said.
Or, as my favourite science geeks, the gang at ScienceDaily.com, put it, “Whole New Meaning for Thinking on Your Feet: Brains of Small Spiders Overflow into Legs“! [2]
“We suspected that the spiderlings might be mostly brain because there is a general rule for all animals, called Haller’s rule, that says that as body size goes down, the proportion of the body taken up by the brain increases,” said William Wcislo, another staff scientist at the Smithsonian Tropical Research Institute in Panama. “Human brains only represent about 2-3 percent of our body mass. Some of the tiniest ant brains that we’ve measured represent about 15 percent of their biomass, and some of these spiders are much smaller.”
(Enormous brains in very tiny packages… Anjouanella comorensis)
The enormous biodiversity of spiders in Panama and Costa Rica made it possible for researchers to measure brain extension in spiders with a huge range of body sizes. Nephila clavipes, a rainforest giant weighs 400,000 times more than the smallest spiders in the study, nymphs of spiders in the genus Mysmena.
So boys and girls, the smaller the spider the more you know that… at least when it comes to brains … size DOES matter.
____________________________________________________________
[1] Yeah, yeah… spiders aren’t actually bugs. I know.
[2] I don’t know who comes up with the article headlines over at ScienceDaily.com or any of the other science geek websites… but they all should get a raise in salary!
koshersamurai 