Female black widows harbor a potent venom containing neurotoxins, substances that destroy nerve tissue. Although they have a fierce reputation, a bite is rarely fatal to a healthy adult human. However, the female arachnid is the one to watch out for; the males are totally harmless to humans.
Black widows undergo this molting process about seven times in their lifetime at intermittent periods of growth when their exoskeleton becomes too tight. For your viewing pleasure, this process has been sped up in the video below.