In consultation with top local statistical expert*, here is the news:
- It is not very surprising that the internet relentlessly quotes 'a quadrillion' as the total number of ants in the world, because this is how the internet works. A 'fact' like this can become a piece of received data by being referenced on Wikipedia, then becoming the answer to the question on things like google and wikianswers, and then, by the nature of Google prioritising things attracting lots of links, becomes a default which is difficult to assail.
(- This is also, loosely, how all received wisdom works, from urban legends to the common mistakes pointed out, often slightly unfairly, by QI.)
- This is not to say the ant stat is wrong. But the original stat comes with a potential error of a degree of magnitude, which is a huge potential error, and so the stat should never be quoted as one single number.
- It is perfectly possible not to know something like this to within a degree of magnitude. Most ants are in places where we can't count them, even with a magnifying glass and whole bag of abacuses. There's probably an ant in your house right now and you don't even know. And don't talk to me about the jungle.**
- Also, the people who could count them most expertly don't have the money to do so, and might not be all that interested. They have other questions that they want to answer about ants, for some reason.
*Local statistical expert not responsible for any errors in this post.
**Yes, yes, this was a bad Cuppy impression.