Since watching this big black bug drag the hairy spider across my porch this morning, I've learned some interesting things. My neighbor thinks the black bug is a tarantula hawk wasp and the spider is a tarantula. I'm inclined to believe that identification after reading about them both, although my wasp didn't have the brown-orange wings that seem to identify tarantula hawk wasps.
Check out this gruesome but fascinating description from Wikipedia:
[The female tarantula hawks] capture, sting, and paralyze the spider, then they either drag the spider back into her own burrow or transport their prey to a specially prepared nest where a single egg is laid on the spider’s body, and the entrance is covered. The wasp larva, upon hatching, begins to suck the juices from the still-living spider. After the larva grows a bit, it plunges into the spider's body and feeds voraciously, avoiding vital organs for as long as possible to keep it fresh.
An unfortunate side story is that something happened to Ellie this morning that left her whining, limping, and out of sorts for a while. Since it happened right before we saw the tarantula hawk and spider, I suspected that the bugs might have something to do with it. I am definitely more convinced after reading this description of the tarantula hawk's sting, also from Wikipedia.
The sting, particularly of Pepsis formosa, is among the most painful of any insect, but the intense pain only lasts for 3 minutes. Commenting on his own experience, one researcher described the pain as "…immediate, excruciating pain that simply shuts down one's ability to do anything, except, perhaps, scream. Mental discipline simply does not work in these situations." In terms of scale, the wasp's sting is rated near the top of the Schmidt Sting Pain Index, second only to that of the bullet ant and is described by Schmidt as "blinding, fierce [and] shockingly electric".