Aphanosauria calcaneal tuber. Although this structure is smaller in aphanosaurs than in pseudosuchians, it is still much larger than in other avemetatarsalians, most of which don't even possess the structure. A few dinosauriformes also have small calcaneal tubers, although aphanosaurs have larger and rounder tubers than these taxa ("Marasuchus" and a few basal silesaurids). In cross-section, the calcaneal tubers of aphanosaurs are oval-shaped, taller than wide. Most foot material is fragmentary in this group, with only a few phalanges (toe bones) and metatarsals (primary elongated foot bones) known. Based on the length of the preserved metatarsals, the foot was likely rather
Effect of spaceflight on the human body on the bones, there is a rapid increase in bone loss, from 3% cortical bone loss per decade to about 1% every month the body is exposed to microgravity, for an otherwise healthy adult. The rapid change in bone density is dramatic, making bones frail and resulting in symptoms which resemble those of osteoporosis. On Earth, the bones are constantly being shed and regenerated through a well-balanced system which involves signaling of osteoblasts and osteoclasts. These systems are coupled, so that whenever bone is broken down, newly formed layers take its place—neither should happen without the other, in a healthy