EL: To summarise the evolution of humans 1. Human Evolution EL: To summarise the evolution of humans

Humans are mammals Humans belong to the class Mammalia Warm blooded Bear live young Hair or fur Mammary glands Teeth comprising incisors, canines, pre-canines and molars Lower jaw made of single bone Three bones in middle ear

Humans are primates Humans belong to the Primate order Dextrous hands and feet with five digits that can grasp and curl (opposable thumb in some cases) Flattened nails on digits that are sensitive to touch Stereoscopic (3D) colour vision Small number of offspring with relatively long gestation Relatively large brains

Primate taxonomy

Humans are Hominoids No tail Five cusped molars Flattened rib cage Locomotion by brachiation, knuckle walking or bipedalism Postures is partially or fully erect allowing hands to manipulate food, care for young or use tools

Humans are Hominins Bipedal locomotion Postures of foramen magnum is centered under the skull Larger brain than other apes – well developed cerebral cortex Smaller jaws and teeth very fine hair Shorter broader pelvis

Hominins over time

Trends in hominin evolution Genus Australopithecus 3.7 Mya Homo habilis 2.4 Mya Homo erectus 1.8 Mya Homo neanderthalensis 0.1 Mya-35,000 ya Homo sapiens 130,000 ya ONLY AFRICA OUTSIDE AFRICA 400-500ml INCREASING BRAIN SIZE 1350ml DECREASING SIZE OF TEETH AND SKULL STRUCTURES (INCLUDING BROW RIDGE) INCREASING TOOL MAKING ABILITY USE OF FIRE CULTURE LANGUAGE

Cultural Evolution Involves transfer of non-genetic info (e.g. stories, beliefs, language, symbols etc) from one individual to another through learning and teaching Very fast transmission – especially now due to technology

Technological evolution Humans have extended their capabilities and control over their environment by applying their knowledge of the natural world – this is technology We were able to do this because of bipedal locomotion and increased brain size

Changing lifestyle of Homo sapiens Hunter-gatherer nomadic lifestyle. Developing cooperative skills and division of labour. Domestication of animals and plants as a ready food source – large sedentary groups develop other skills. Increase in human population. Industrial revolution has led to increased use of technology. Last two hundred years – rapid technology change impacting on culture and biology.

Where do we come from? Two theories Out of Africa Regional continuity

Out of Africa Humans originated in Africa around 100,000 years ago Based on mito DNA and nuclear DNA

Regional continuity Modern humans evolved independently in many regions of the world and have been exchanging genes for at least one million years

Homework Complete activity 15.4 Chapter 15 quick check, biochallenge and chapter review questions

Reflection Will the facebook posterhelp you to remember the hominid species? How else could you remember key details about them?