Anthro2050 1st Edition Lecture 24Outline of Last Lecture I. Sites and Geology ContinuedII.Humans and ApesOutline of Current Lecture II. Humans and Apes ContCurrent LectureHumans and Apes Cont:-Chins: Apes and early humans had no chins, it started appearing closer to modern humans. Human chins have a thicker enamel than apes without chins.-most changes in body below cranium are due to bipedalism-major shift in centre of gravity for balance-vertebral column curvature made so the spine better supports un upright body-thorax shape: apes- funnel shaped, narrow at the top then spread out at the bottom. bipedal hominids- barrel shape, narrow at top and bottom to give extra support to organs.-pelvis: apes-more narrow and set to the back. with bipedalism, the pelvis widens and is more set to the side to allow for two legged walking- valgus angle: angle between the femur and the proximal tibia. This angle brings the knees in closer to the center of gravity, allowing for easier walking without falling over. In quadruped apes this angle does not exist, as it is unnecessary, which is why apes walk in a swaying motion when they try to walk on two legs. This angle forms in humans only after they learn to walk, which is why babies just learning to walk also walk in that swaying motion.-big toe: apes have an off-set, fully opposable big toe, while human big toes are close to the other toes and are not opposable. this is because apes use the feet like hands and need the toe These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.to aid in grasping, while human feet need to be rearranged to support walking and balancing ontwo legs, as well as taking all the body weight on two feet.-ratio of arms to legs: in quadrupeds, the arms and legs are close to equal length. In knuckle walkers and brachiates, the arms are longer than the legs. In bipeds, the legs are longer than the arms. In the human fossil record, we see this transition from longer arms to longer legs -thumbs: apes have a small thumb that is not very mobile. what makes humans distinct is the ability of the thumb to cross the palm and touch the tips of other fingers. Apes cannot do
View Full Document