"The birds didn't stop their pecking until the squad leader was bleeding and no longer moving. The rest of the aliens grabbed the human and ran for their lives. 'What were those?' the human was later asked. 'Geese.'"
The aforementioned ostrich aside, I've had some pretty scary encounters with animals that a lot of people don't take too seriously. Deer. Turkeys. Swans. Even an obnoxiously aggressive squirrel. It always gives me a chuckle to hear how scared zoo visitors can be of the wolves, alligators, and other relatively placid animals, while not appreciating just how dangerous some of the other animals can be.
"It's just Bambi," they'll say. Yeah, trying saying that when Bambi is in rut and is trying to ram you in the gut with those antlers. He won't seem so sweet and lovable when he's prancing around wearing you as a hat.
I was super amused to read this feed, which imagines an alien invasion of our planet. Remember in H. G. Wells' War of the Worlds when (spoiler alert) the invading Martians, after laying low our human armies, are decimated themselves by the common cold? Imagine that they never made it that far. Instead, the found themselves slaughtered in droves by earth's animal life, ranging from the obviously lethal, like leopards and tigers, to the what's-the-worst-that-could-happen?, like cows and emus. And geese.
If there is one smug consolation for the human characters in these short stories, it's that they can all go, "Can't say we didn't warn you..."