This should explain what quokkas are (RE: re: Re:^634 The Walk on the Moon).
Over a year ago, when I was at college, one of our staff left to work at the university in Perth, Australia. Our department was such that we tried to hold a party for the staff and post-graduates whenever we could and Kevin's leaving seemed like a good reason to dip into the funds to buy some booze.
Kevin told us of one animal which slept in trees which they sometimes fell out of. Apparently, this was so common that the guide asked tourists to avoid walking under trees in case a quokka should fall on them.