In a few cases, amber has preserved spiders' egg sacs and webs, occasionally with prey attached; the oldest fossil web found so far is 100 million years old. Earlier spider fossils come from a few lagerstÃ¤tten, places where conditions were exceptionally suited to preserving fairly soft tissues.
Definition of METATARSAL. : of, relating to, or being the part of the human foot or of the hind foot in quadrupeds between the tarsus and the phalanges that in humans comprises five elongated bones which form the front of the instep and ball of the foot. See metatarsal defined for kids.ADVERTISEMENT. of, relating to, or being the part of the human foot or of the hind foot in quadrupeds between the tarsus and the phalanges that in humans comprises five elongated bones which form the front of the instep and ball of the foot. See metatarsal defined for kids. ADVERTISEMENT.
1 Shoes that do not protect the ball of your foot include high heels; shoes with thin, flexible soles; or shoes without sufficient support. 2  A stress fracture. 3  A crack in one of the metatarsal bones, called a stress fracture, can be caused by overuse or by normal stress on a metatarsal bone if you have low bone density. number of activities and conditions can cause pain or increase pressure on the ball of your foot (metatarsal area). These include: 1  Certain sports. 2  Running, walking, standing, or jumping, especially on hard surfaces like concrete, increase the impact on the ball of the foot.