Spiders

Orb weavers (Family Araneidae) comprise a huge family of spiders, of which there are several hundred species in North America. These spiders vary greatly in color, shape and size, measuring between 2 - 30 mm (1/16 -- 1 1/4") long. They have eight eyes arranged in two horizontal rows of four eyes each. The males are generally much smaller than the females and commonly lack the showy coloring of their fairer sex. They often spin their own smaller orb web near an outlying portion of the female's, and I've noticed most males give the females wide berth. Indeed, I rarely see male orb weavers, they are so reclusive.

Jumping spiders (Family Salticidae) get their name from the sometimes spectacular leaps they make when pouncing on prey or simply hopping about in the foliage. They are very small to medium sized spiders 3-15mm (1/8 -- 5/8") long.

Their eight eyes are arranged in 3 rows - the first row near the midline contains the largest pair, which faces forward in the manner of predatory animals requiring binocular vision, and a second, smaller pair outboard of those, also facing forward and slightly upward. The second row of eyes is very mach smaller and facing upwards and only slightly forward. Our page on the bold jumping spider, Phidippus audax has many pictures showing the jumping spider's eye arrangement. The jumping spiders have the most acute eyesight of all spiders.

Salticids do not build webs to snare prey, they only spin small silken retreat webs under leaves, bark or twigs. When hunting, jumpers always trail a silken strand from their spinnerets. If they are disturbed, they will rapidly descend on this lifeline to the ground and out of sight, or if they miss their jump, they can climb the thread back to their previous perch. Salticids are very adept at hiding, and if they do not want you to see them, you won't. It rarely bites people and causes only mild local pain.