When this video started making the rounds this week, we sensed it was time to dig a bit deeper into this palaeontological puzzle. Seemingly taking inspiration from this awesome comic by The Oatmeal, the video claims "that almost every single molecule" of water we consume has at one time been drunk (and subsequently urinated out) by a dinosaur. But it turns out that things are not quite that simple. We checked in with palaeontologist Jon Tennant to get the full scoop. 

"This seems a bit like the 'study' claiming dinosaurs farted themselves to death. It's a nice idea, and a [fun] conclusion, but the video doesn't go into much detail and there are quite a few assumptions being made here," he says.

For starters, Tennant explains that the amount of water available on our "pale blue dot" hasn't always remained the same. And he also notes that estimating total dinosaur biomass from the fossil record is pretty much impossible.

"And even then," he says, "using that number to work out the entire [water consumption calculation] is inaccurate because things changed over time. At certain points there were loads of big dinosaurs, and at different points loads of small ones, and sometimes, very few of either." What's more, the video also makes the assumption that dinosaurs had the same water requirements as modern-day animals.

But we don't want to ruin this for you completely. Yes, there's a good chance that some of the H2O we guzzle down has, at some point in our planet's history, trickled its way through a dinosaur – but determining how much involves just a little too much guesstimating. You're probably better off choosing a dinosaur companion animal.