Big birds of history.
Actually the biggest birds.
(If you don't count dinosaurs).
Let me start again.
The biggest birds than humans ever encountered.
Mostly in history.
Because then we killed them all.
Leaving just ostriches and stuff.
(Which can still be quite scary.)
Okay, one more go.
On my holidays, I went to the Norwich Castle Museum. In the Natural History section they have an elephant bird leg bone.
I have elephant bird leg bones before. Yet somehow when they are stacked on top of each other, the scale really catches up with you.
This is a case full of interesting stuff. Bottom right is a gannet skeleton, plunge diving into a guinea pig skeleton (of course), with a passenger pigeon skeleton hiding behind it (which is really quite small). Out of shot but in the top left of this cabinet is a terror bird skull, just in case big birds of history weren't scaring you enough. (That's three extinct species in just one case... and doesn't include the Great Auk).
After seeing the elephant bird leg, I really needed to get a sense of scale, but have struggled to find any good diagrams online. So I have made my own. The elephant bird (Aepyornithidae, of Madagascar) is closely related the moa (Dinornithiformes, of New Zealand) and kiwi (the same clade), and are built along the tall running ostrich/emu/rhea/cassowary shape (at least tow of which were stuffed in other cases).
The terror bird, Phorusrhacidae, formerly of South America is built more along the tank/tyrannosaurus model, so isn't as tall but I still wouldn't get into a fist fight against (and it doesn't even have fists).
Fortunately all these birds are recently extinct, so you won't run into any of them, except perhaps the noted yellow "big bird", which I have seen documentary footage of.
This is a small section of one case amongst many, just in the Norwich Natural History gallery. I hope to write more blog posts on the bleached blonde girls of the African savannah, the cut-and-shut scimitar-horned oryx, and I would be especially grateful if anyone could fill me in on the identity of the random human giant skeleton reading a book in one of the cases in the back corridor. No one seems to know anything about him and I am wondering if it is a very clever mafia body-disposal method.