Almost as soon as the first Dwarven caravan showed up on the map, one of their axe dwarves ran full steam ahead to attack a huge group of gorillas.
As he was killing gorillas, the merchants (and their mules and their other axe dwarf) kept slowly plodding towards my fort. The distance between them and the axe dwarf got very large very quickly, as he was chasing gorillas all over the place.
The plodding caravan then came upon a couple more gorillas. Before the remaining axe dwarf could take them out, they killed a mule.
At this point, the merchants, their remaining mule, and the axe dwarf who had stayed with them turned tail and ran off the map. They hadn't even gotten anywhere near my fort.
Meanwhile, the crazy axe dwarf was still chasing gorillas all over creation - nowhere near the caravan. He didn't seem to show any signs of thinking "Hey, my caravan's leaving, maybe I should leave with them instead of charging headlong into faraway packs of gorillas".
Eventually, he was killed.
So, free gorilla meat. Free mule meat. Free caravan stuff that was on the mule. And free armor and weapons from the killed axe dwarf - far better than anything I could produce at this time.
But, now I'm wondering:
Will caravans shun me from now on? At least for a while?
And how about immigrants? As I understand it, the number of immigrants you get depends upon how much of the caravan you bought out.