You have to wonder sometimes, who looked at a cow and said, "I think I'll squeeze those hanging things under it and drink whatever comes out."
But then, if you think logically, they probably saw the calves drinking from those dangly things (aka udders) and put two and two together. Baby humans nurse, so maybe that calf is doing the same thing (or lamb, kid, foal, whatever animal we happen to milk).
Then there's the whole egg thing. Who in the right mind saw that THING come out of the rear end of a chicken (or duck or goose) and said, "I think I'll eat that. It looks mighty appetizing, having just come out of chickenbutt." (And as someone who now collects her own eggs, I can say that sometimes they're nice and clean looking and all pretty, and sometimes they're covered in chicken poop. Gross.)
But again, logically, they probably saw how other animals ate them (foxes, rats, other birds, sometimes the chicken that just crapped it out). So they thought, well, if they can eat it, why can't I?
And really, makes sense. People see animals eat something, they can usually assume it's safe for human consumption. (USUALLY. I'm not saying that whatever rotten thing your dog picks up and chews should be put into your mouth). But really, it's a good way to figure out if something tastes good and has any cool benefits. Like coffee.
But you've REALLY got to wonder who looked inside the barrels that were used to ferment beer and said, "Hmm.... that brown goo on the inside of the barrel looks tasty. I think I'll scrape it out and put it on some toast!"
Ok, ok, so there's more to the story, and it's somewhat interesting, if you're into food development and/or Vegemite. So, yay Wikipedia, here you go.
It is a truly Australian food. And aside from eating the national animal, kangaroo, should you ever visit, this is a must-try. Just don't spread it an inch thick on anything. Because all the rumours are true: it's salty and kind of foul. Unless you're like me, and you LOVE salty goodness, and you've been trained in proper Vegemite application. For breakfast, (I seriously do love saltiness for breakfast) first smother your toast in butter. Then oh-so-thinly, as if just barely trying to paint your bread a darker colour, spread the Vegemite. Or do this on a cheese sandwich, or cheese and cucumber. It's really quite delicious.
Just try not to think about where it comes from. Like your morning eggs.