Female wolf spiders provide both their eggs and young with a considerable amount of maternal care. They actually carry their egg sac around with them, attached to the spinnerets at the end of their abdomen, as they hunt for food and go about their lives. Careful to keep her egg sac from touching the ground, the mother makes sure it receives a sufficient amount of sunlight each day, presumably to enhance incubation. She also mends any tears that appear in the sac. The eggs hatch in one to two weeks, and 4 to 22 days later, the mother perforates the egg sac either part way or all the way around the seam by rotating the sac with her legs as she makes tiny holes in it with her chelicerae (mouthparts). Within three hours of this, spiderlings crawl out of the sac through the holes made by the mother, climb up onto her abdomen (see photo), and remain there for days or weeks, depending on the species.
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