Biological and cultural evolution of the hominins Year 13 Biology Achievement Standard 3.7

Possible family tree of the various hominins

Characteristics of the very early hominins Using pages 306 – 320 of your CB book, create “recipe cards” to help you learn the biological and cultural evolution of the following fossils. Remember: you need to know TRENDS in the biological and cultural evolution of humans, however learning the names and features of each of the important fossils will help you put the picture together.

Characteristics of the very early hominins Sahelanthropus tchadensis Australopithcus genus A. ramidus, A.anamensis, A. afarensis, A. Africanus Paranthropus genus P. aethiopcus, P. robustus, P. boisei Homo genus H. Habilis, H. erectus (asian), H. ergaster (african), H. Heidelbergensis, H. neanderthalis, H.sapiens idaltu, H.sapiens

Cultural Evolution trends Sahelanthropus tchadensis Lived in wooded areas Most of cultural evolution is pure speculation Australopithecus group Only debatable evidence that they made tools, and no evidence that they had home bases or shared food. Probably opportunist feeders. Paranthropus genus Some evidence they used bones or perhaps sticks to dig up roots (this would leave no fossil evidence though) Evidence suggests robustus ate course, tough food supplemented by small insects.

Cultural evolution trends Homo genus Development of speech Enabled by Broca’s area of the brain. First seen in H.habilis. Development of tool-making H. habilis was known as the Handy man and made Oldowan tools. H. erectus used Acheulian tools and was known as the Fire maker. H.Neanderthalis used Mousterian tools and began to attach stone tools to handles. H. sapiens used advanced tools of flint and bone. Used blades and points. Called Upper Palaeolithic tools.

Cultural evolution trends Homo genus Development of group living and culture H. habilis – successful hunters, made shelters and lived in bands of about 12 people H. erectus - built shelters (huts) supported by wooden poles, serious co-operative hunters H. heidelbergensis – able to hunt large prey (rich diet led to increased size), were cannibals, built shelters and used fire H. neanderthalis – intelligent, lived in caves, built stone walls, dressed in hides, buried their dead, had strong social bonds. H. sapiens – skilled hunters, lived in large groups, engraved and painted on walls, carved statues etc

Cultural Evolution in Humans Can be defined as; Tools, books, writing, art, language, music, ritual etc Is passed down by teaching (oral or written) Is fast

The home base theory At some sites, concentrations of tools, stones from other areas and bones are found. This suggests that early hominins were not just carrying things around, but were focusing on one site as a home base. Adults hunted and left young behind, and then brought all produce back to be shared Sharing of food lead to complex societies Clearly defined by the time of Homo erectus

Communication Facial expressions important Speech Culture requires intelligence and communication Areas of the brain essential for structure and sense of speech Broca’s area – concerned with speech Wernicke’s area – concerned with comprehension of language The lower the voice box, the more sounds can be articulated.

Communication Singing and chanting Essential for remembering kinship lines and tribal history Better hearing and listening skills as a result of speech Art – drawings of pictures and symbols on cave walls, bone carvings, clay statues

Development of Agriculture Learning to cultivate a food-producing plant; not just gathering a naturally occurring plant. Domestication of animals – dogs, sheep, goats, pigs, cattle Why start agriculture? Population expansion Shortage of food Climate change Need to be near a constant water supply

Development of Agriculture Disadvantages; Living close together means chances of diseases spreading is increased Diet not as varied so could have suffered from malnutrition Stored food could spoil

The dispersal of humans

The Multiregional Theory Extending from the populations of H.erectus there were populations of humans living around the world, and all of these contributed to successive generations – eventually leading to modern humans. In other words – Homo sapiens evolved independently in several places around the world.

Predictions of Multiregional Transitional forms found in many places Modern traits should appear around the world simultaneously There should be a high degree of diversity in humans as Homo sapiens is a very old species

Evidence for Multiregional Asian fossils show a clear transition from older hominid to modern H.sapiens The oldest H.sapiens fossils outside Africa were in Australia, and are 60 000yrs old. Northern china fossils show no evidence that African features ever replaced the ancient Chinese in this region Instead there is a smooth transformation of ancient peoples into the present populations of East Asia and the Americas.

Evidence of Multiregional Post-Neanderthal people in Europe show mixtures of modern and archaic African features Mitochondrial DNA analysis is flawed because; Present-day patterns cannot show links that become extinct Whenever no daughters are produced the mitochondrial line dies out

Replacement – “Out of Africa” model Intial migration of early Homo, such as H.erectus, H.heidelbergensis and H.neanderthalis, did not contribute to modern humans, but there was a second wave of new humans out of Africa approx 200 000years ago. It was a fully modern H.sapiens that then replaced whatever populations then occupied Asia and Europe

Predictions of “Out of Africa” Transitional forms found mainly in Africa Modern traits found first in Africa and then later elsewhere as they spread Since the species is young there should be little diversity

Evidence for “Out of Africa” Mitochondrial DNA shows high degree of similarity between all modern human populations that most likely occurred with the past 150 000 – 200 000 years ago The oldest H.sapiens fossils have only been found in Africa, 80 000 – 120 000 years old Humans arrived in Europe late – about 80 000 years ago

Evidence for “Out of Africa” Mitochondrial DNA of Neanderthals, Cro-Magnons and 21st century Europeans that was compared and showed: Modern humans showed similarity with Cro-Magnons Modern humans showed no similarity with Neanderthals Mitochondrial DNA all lead back to Africa, showing that Africa is the place of origin for modern humans. Large levels of gene flow between continents would be required for multiregionalism (unlikely)

Evidence for “Out of Africa” Fossil evidence shows that moderns humans appeared in Africa before the Neanderthals had disappeared in Europe so could not be descendants of the Neanderthals