Question: How many organisms are in the world today?

Gloeta Massie answered on 13 Jun 2011:

That’s a great question! I haven’t a clue – especially since we keep finding new ones every day! Plus, there are lots of discovered animals that haven’t even been studied yet – so they’re not even counted. (For example, there is a blue-ringed octopus species that is simply known as Hapalochlaena species 1). On a REALLY cool-to-think-about-level is how many different organisms are living on you and me. Did you know that we have over 500 different species of bacteria that live on/inside of us? But – even crazier – they outnumber us around 10 to 1! Yep, for every one of your cells, you’ve got around 10 bacterial neighbors! WHOA! (Check out: Normal microflora: an introduction to microbes inhabiting the human body by Gerald W. Tannock). And, what about those eyebrow mites that crawl around and eat the dead skin in our eyebrows. If you listen really closely – you can hear them chomping away. (Ok. Maybe not. But, it would be a cool party trick if you could!)