Radius

Features.of.the.radius........................................................................... 129. Human.(Homo.sapiens)................................................................131. Moose.(Alces.alces)..................................................................... 133. Elk.(Cervus.elaphus)................................................................... 133. Deer.(Odocoileus.sp.).................................................................. 134. Bison.(Bison.bison)...................................................................... 134. Cow.(Bos taurus)......................................................................... 135. Antelope.(Antilocapra americana)............................................. 135. Mountain.sheep.(Ovis canadensis).............................................. 136. Domestic.sheep.(Ovis aries)........................................................ 136. Domestic.pig.(Sus.scrofa)............................................................ 137. Llama.(Lama.glama)................................................................... 137. Horse.(Equus).............................................................................. 138. Bear.(Ursus.americanus)............................................................. 138. Wolf.(Canis lupus)....................................................................... 139. Coyote.(Canis.latrans)................................................................ 139. Mountain.lion.(Felis.concolor).................................................... 140. Bobcat.(Lynx rufus)..................................................................... 140. Raccoon.(Procyon lotor)..............................................................141. Badger.(Taxidea taxus).................................................................141. Skunk.(Mephitis mephitis)...........................................................142. River.otter.(Lontra canadensis)...................................................142. Rabbit.(Lepus.sp.).........................................................................143. Beaver.(Castor canadensis)..........................................................143. Porcupine.(Erethizon dorsatum).................................................. 144. Marmot.(Marmota.monax).......................................................... 144. Prairie.dog.(Cynomys gunnisoni).................................................145. Norway.rat.(Rattus norvegicus)....................................................145. Squirrel.(Sciuridae sciurus niger)............................................... 146. Armadillo.(Dasypus.novemcinctus)............................................ 146. Opossum.(Didelphis.virginiana)..................................................147. Seal.(Phoca.vitulina)....................................................................147

The.radius.and.ulna.are.the.bones.of.the.forearm,.and.are.separate.bones. in.humans...The.radius.moves.over.the.ulna.in.pronation.in.humans.and. in.some.other.animals,.but.in.many.animals.the.bones.are.fused.and/or. the.ulna.is.significantly.reduced.in.size.so.as.to.make.rotation.impossible. .....In.humans.the.ulna.articulates.with.the.radius.distally.at.the.ulnar. notch...In.those.animals.in.which.the.ulna.is.fused.or.reduced.in.size,. there.may.be.no.ulnar.notch.(arrow.points.to.ulnar.notch.in.humans). .....Because.the.radius.and.ulna.are.fused.in.some.animals,.some.of.the. following.photographs.of.the.radius.also.show.the.ulna. .....Note.some.general.differences.in.the.photographs.(proximal.aspects. top.photograph,.distal.aspects.bottom).