Unfortunately, it was the human variety! Around noon today my buddy and I encountered this person (white male, 60-ish, gray beard, wearing a black coat with hood) who was walking down the middle of the MVT with a 10 lb dumb bell held in each hand at shoulder height. We slowed and gave an audible warning. No reaction. Slowed to dead slow crawl and repeated the warning. No reaction. Passed on left at a crawl with feet on the ground. The person started ranting about cyclists not knowing the meaning of "slow down", accused us of running stop signs, etc. He then made an aggressive move toward me and bumped me off the trail. We rode away from him while he continued an incoherent rant about cyclists and the handicapped. Zero idea what his problem was. Well, life is way too short to deal with people like him. So, we reported him to the Park Police who have had previous reports of him. They are going to be on the look out for him. Just be careful! Tom