The widow spiders all release a neurotoxin. The brown recluse releases a hemotoxin. Hemotoxins affect blood cells and skin tissue in the bite area, whereas neurotoxins affect the nerves and nerve tissues. Hemotoxins attack skin tissues to assist in digestion. The neurotoxins assist in immobilizing and death through, basically, suppression of respiratory functions. Neither spider is considered aggressive, but due to their normal places of residence bites are generally from accidental contact. They both like to remain in hidden or covered areas, such as woodpiles or stacks of junk. People reach in or under to grab something without looking.
I've never watched a brown recluse, because I never had any, but I have watched black widows. I used to keep a pair of females (separated from each other), on the desk in my office at work in a plexiglass "cage" I had constructed. Whenever I'd drop in an insect that was alive and would struggle in the web, the spider would immediately attack and bite in order to paralyze. If the "food" didn't move much, the spider would take her time before moving in on it. I can only surmise the immediate attack was in order to minimize damage to her web.
Some of my coworkers thought it was pretty morbid and objected to them being there (Screw off, it's my office. stay the hell out then! LOL). Others were fascinated by them. Some to the point that they would come in when I wasn't there and open the cage to try and feed them. I ended up having to construct a lock setup for the lid. I also made a warning placard to inform folks they were poisonous spiders. Many of my coworkers had never seen a black widow, even though they're very common...if you watch for them. As such they served as an education tool and my supervisors never questioned or complained about them.
Again....more useless info you could live without! LOL
