Question: how big can the biggest land animal get?

Vera Weisbecker answered on 21 Jun 2011:

That is a difficult question because we have no guarantee that the biggest land animal that ever lived also reached the biggest possible size for a land animal. But as far as I know, the biggest land animals were the giant sauropod dinosaurs. There is a debate as to which sauropod was the biggest (Wikipedia says it’s an animal called Giraffititan), but there are quite a few in the 20ish m length/10ish m height/60ish ton weight range.

I suspect that sauropods were pretty close to the largest animals that could ever exist, because at those sizes you have a lot of issues with gravity (e.g. your bones may just not be able to be functional any more at such giant weights), tissue maintenance (it is hard to shunt blood to all the parts of your body if you are that large), feeding (imagine how much you need to eat to fuel 60 tons of meat and guts!) and growth rate (e.g. life is too short to grow bigger sizes).