I can vouch for kangaroos being dangerous. My only scar from my time as a zookeeper is from a Kangaroo bite. I worked with Arabian Oryx, Bonteboks, Sika Deer, Bongos, Havalenas, Cheetahs, Rhinos, and Zebras. All of them were dangerous in their own way (the Arabian Orxy attempted to kill me every morning). But the roo was the only one who managed to injure me (I had to pin her down for her shots).
I love animals, but there are certains ones that should not be domesticated. Admire them, love them, but leave them in their proper habitat!
**Edited because I do know the proper form of there!**