An illustrated wide floodplain in warm morning light, several large long-necked plant-eating dinosaurs standing in a shallow river drinking, their reflections in the still water, ferns and conifers along the banks.

What did dinosaurs drink?

Water, the same as us — and, the flagship page argues, almost certainly some of the very same atoms. Which water, from where, and whether any of them could have managed the sea are separate questions, and each of the pages below takes one of them.

AI reconstruction — not a photograph · Shutterstock AI/Shutterstock.com · Shutterstock Standard License

Five questions, five answers

Is the water we drink dinosaur water?“Almost certainly, yes” — with the sums shown, and the reason nobody can follow a single molecule from a dinosaur to your glass.
What did T. rex drink?Water, because there was nothing else to drink, and then the better question of how anyone knows T. rex was there at all.
What did Spinosaurus drink?Water again, the only answer the evidence supports, followed by where the animal has actually been found and how few times.
What rivers did dinosaurs drink from?“Rivers with no names, which nobody has ever seen” — though the rock one of those rivers left behind is still there to read.
Did dinosaurs drink seawater?“Nobody can say yet”: whether dinosaurs had the gland that gets rid of the salt is an argument between named people, still going on in print.

Real photograph · AI reconstruction — not a photograph: James St. John, CC BY 2.0, via Wikimedia Commons · Wirestock Creators/Shutterstock.com · tolobalaguer.com/Shutterstock.com · 228988681/Shutterstock.com · Shutterstock AI/Shutterstock.com · CC BY 2.0 · Shutterstock Standard License · Shutterstock Standard (free image collection, API) License

How the five fit together

If you only read one, read the flagship, because that is where the arithmetic lives. The T. rex page sends you there for the sums rather than doing them a second time.

The T. rex and Spinosaurus pages give the same one-word answer at the top. The rest of each page is about how we know the animal was there at all, which is where the evidence is.

The rivers page and the seawater page are the two where the answer is not simply “water”. One has rivers that nobody can name, and the other has a question that nobody can settle yet — and both say so rather than guessing.

Where next

To see the world those animals drank in, try What did Earth look like when dinosaurs lived? and What oceans existed during the dinosaurs? The question of how old the water itself is has its own page too: How has Earth’s water changed through time?