Class Notes (835,243)
Canada (509,044)
Anthropology (1,915)
ANTHROP 1AA3 (1,018)
Lecture 7

ANTHROP 1AA3 Lecture 7: First Humans

8 Pages
Unlock Document

Karen Mc Garry

Thursday, November 3, 2016 First Human When and Where Did the First Humans Appear? - there are approximately 190 species of non-human primates - Primates cant be easily defined by a few traits - we can see evolutionary trends instead - limbs and locomotion - dentition - sense and the brain - development - origins from arboreal life Locomotion forms - Brachiation - Bipedalism - Knuckle walking Hands and Feet (and tail?) - hands and feet are prehensile (grasping) - five digits n hands and feet, but some show diminished thumb and second finger - Partially opposable thumb and most have fully divergent, partly opposable big toe - Nail instead of claws (except some New World monkeys) - Tactile pads with nerves at ends of fingers to enhancee touch sense 1 Thursday, November 3, 2016 Primates Have Generalized Dentition - Change in dentition — primates moved from eating insects to more fruits and vegetables to becoming omnivorous — adaptation of teeth is probably caused by natural selection, so that the kinds of teeth best able to accommodate a particular diet enhanced over time Sense and the Brain - Colour vision — all diurnal have it, nocturnal do not - Depth perception — stereoscopic vision allows to see in 3 dimensions - Binocular vision — both eyes set toward front of head - Decreased reliance on sense of smell (olfaction) — reduction in sensory areas of brain and in snout - Expansion and increasing complexity of brain- visual areas and areas having to do with hands Development - more efficient fetal nourishment, longer periods of gestation, smaller numbers of offspring, delayed maturation, extension of whole life span - Greater dependence on flexible, learned behaviour greater parental in offspring - Tendency to live in social groups and permanent association of adult males with the group, male association uncommon in all but primates - Tendency for diurnal activity patterns So… when did humans evolve? - Evidence lies in analyses of fossils and HOMININ ancestors (bipedal ancestors of humans) who lived in East and South Africa 2 Thursday, November 3, 2016 What does a Hominin Look Like? - Small front teeth and large molars - Bipedalism and associated anatomical adaptations - high manual dexterity Australopithecus afarensis (4 mya) Bipedalism — why? - transition from tropical rainforest to savanna - easier to spot predators - thermoregulation — better dispersion of body heat? — bipedalism limits the area of the body directly exposed to the sun, also helps with heat loss by allowing heat to rise up and away from body - free hands — for harvesting wild foods; tool use- but tool use appears AFTER bipedalism emerged How Can You Tell if Something is Bipedal? 1. Position of foramen magnum (shown in red) - Hominid spine has to distinctive curves (S-Shaped) - Shape of pelvis — broad and low. Early hominids more like human pelvis - Length of lower limbs (humans longer) - Structure of femur and knee - Shape and structure of the foot (arch) 3 Thursday, November 3, 2016 The Australopithecines (4-1 Mya) - Gnus — Australopithecus - Many diff species recognized - found exclusively in East and South Africa - Significant role in human evolution Defining Features of Australopithecine (Raymond Dart): - Bipedalism - Higher Degree of sexual dimorphism than humans but less than apes - Cranial capacity of 350- 600 cc - Large post canine dentition relative to humans; thick enamel - 30—55 kg; Height: 1.2-1.5m - High brachial index (forearm/upper arm ratio) compared to other hominids Lucy — Australopithecus Afarensis; discovered by Donal Johnson - 40% complete - Helped us understand - adaptations to bipedalism Did Australopithecines eat meat? - Maybe. In 2005, at the site
More Less

Related notes for ANTHROP 1AA3

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.