Difference between revisions of "History 8 Human Origins Concepts"

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Concepts:

Advantages and disadvantages of bipedalism

The advantages of being a biped is that it saves your energy, helps you see over things, and and gives you a better chance of survival and reproducing. However, there are many disadvantages, like the fact that if you are standing high predators can see you much more easily. Also bipeds are much slower than quadrupeds because they use two limbs instead of one.

Australopithecus Lifestyle

Australopithecus travelled in medium sized groups conveying that these animals were social. But the male specimens are much larger than the females (sexual dimorphism) indicating that there is a larger difference in the roles of males and females in the group. They had not yet developed tools but sometimes may have stumbled upon a twig and used it to eat termites, making them opportunistic animals. We can tell from their teeth that these creatures were, for the most part, vegetarians. Australopithecus was also pair-bonded, meaning they had a mate for life. They mainly slept in trees but occasionally would take shelter in a cave to get away from a predator or the rain.

Reasons for extinction of Australopithecus

Homo habilis Characteristics

The Homo habilis developed on Earth 2.3 million years BC. These hominids had a 50% larger brain than the preceding australopithecines, and ate both plants and animals. This ancient creature is known for the ability to make tools, hinting his name the Homo "habilis", habilis meaning "handy man". Standing and average of only four feet tall, and weighing no more than 110 pounds, the Homo habilis were hardly a modern day human size. The teeth of the habilis were black, and smaller than the australopithecines. One of their most unique features was their ability to sweat. Sweating allowed them to keep their body temperature down, so they could hunt in the heat of day. The Homo habilis were a great step forward in the evolution of humans. Two helpful sources were the: http://www2.sjs.org/beniretto/Origins (The origins section of the lab manuel pg. 17) https://www.msu.edu/~robin400/habilis.html

*Effects of Meat in diet

**Sweating

Anthropologists agree that the Homo Habilis adapted to their warm climate by sweating. It is quite possible that these early hominids chose to hunt and gather during the hottest part of the day, when the other large predators were resting. Over many thousands of years, this practice might have led to the adaptation of sweating. Homo sapiens swear more profusely than any other animals, even though their sweat glands are about the same size. Sweating provided the homo habilis with a solution to a high-temperature living life, since sweating keeps body temperature down.

However sweating also had a few restrictions. The steady loss of water meant that hominids had to live near areas that drinking water was accesible. Living nearby a water source became necessary for daily life and for hunting.

See P. 18 Manual

**Factors in Brain growth

There were many factors in the brain growth of H. Ergaster and H. Erectus. Their diet began to include meat and the protien and nutrients from the meat gave their brains the necessary vitamins to grow and expand. Also, their means of getting food - hunting and scavenging - demanded more intelegence, to coem up with tactics concerning how to find food and what is good to eat. Also, the actual actions of making prmiative tools literaly expanded the brain capacity. Lastly, the search for material for tools required memory, unlike just eating grass os picking leaves off a tree did. For more information, go to page 18 in the the manual.

**Problems with large brain/solution

H. ergaster/ H. erectus Characteristics

1.9 million years ago, another species of Homo named Homo Ergaster (the worker) emerged in Africa. This species is also known as Homo Erectus, which is sometimes used for later populations in Asia. Homo Ergaster had a rounded cranium and a prominent browridge. Its teeth were also reduced in size. Several features that distinguish H.Ergaster from H. Erectus are thinner bones of the skull and the lack of an obvious sulcus (a depressing just behind the browridge). The average was measured 950cc to H. habilis 800cc. Using this improved mental capability, H. Ergaster took to the art of tool making beyond just chipping rocks. They developed the ability to make symmetrical pear-shaped hand axes. They made it easier for H. Ergaster to butcher carcasses of meat and clean the flesh off the hide. The sharing of this meat also allowed relationships to develop in the community. They also used different sounds to communicate with each other. Food also led to conflict between H. Ergaster. They fought over food and mates more often then other species.

**Climate and its effects

From about two million BC to 8,000 BC, it was not particularly comfortable anywhere in the world. Variations in the Earth's orbit and constant shifts in the shapes of the continent caused a constantly-changing climate, alternating between ice ages and warmer periods called intergalcials, alternating every hundred thousand years. During an interglacial, such as as one we are experiencing today, the regions near the equator experienced frequent rainfall, and the southern and northern parts of the world experienced temperate climates. Each 9interglacial period eventually grew colder, and ice spread to the south until it covered to europe and North America. Northern Asia was free of ice because because it lacked rain. Then after a few thousand or even a few hundred years, the glacial period reached a peak and was replaced by a new interglacial period, and they cycle repeated.

* Glacial periods

In the year 16000 BCE, about the time the most recent Ice Age was at its climax, parts of North America and Europe reached temperatures as much as 65˚F lower than they are now. Between one-third and one quarter of the Earth's land surface was covered in ice, sometimes two miles deep. Significant changes in Earth's geography and climate occurred because so much of the water was locked up in these ice sheets. Sea level dropped dramatically, by about 410 ft, uncovering boundless areas of what was seabed before. The effects were huge, from rainfall levels plummeting to whole bodies of water drying up to a huge new continent emerging in Southeast Asia. Also, vegetation was scattered by fierce winds. Because of all that, Earth's vegetation belts moved much closer to the Equator than they are currently. Human beings were compelled to adapt their lifestyles to the mass of effects the glacial periods had on the world. In the process, they developed hunting strategies that allowed them to survive the Ice Age.

Fire

Human Evolution experienced a 1.5 million year pause until Homo Ergaster discovered fire. The exact date of the discovery of fire is not known. The discovery of fire enabled hominids to migrate to the colder climates of Europe, Asia, and beyond. By 300,000 B.C., Homo Heidelbergensis was using fire to drive large game to the edges of cliffs and other areas that made it easier for them to make a kill. The discovery of fire sparked new advances in human evolution, leading eventually to Homo Sapiens, or modern humans. An excellent source for fire can be found in the Manual ( [[1]] ) Page 22.

**Social development

When hominids started giving birth to babies whose brains had to do most growing outside of the womb, children could no longer be raised only by their mother, because they were much more dependent, especially during the first years of their lives. Men and women had to work together to bring up the children, which required building relationships. The more dependent young also created the system of men hunting and scavenging away from their home, while women stayed closer to the babies and looked for vegetables to gather.

H. heidelbergensis

The H. heidelbergensis existed during about 800,000 BC to 300,000 BC and were nomadic, usually in bands of 20-30 individuals. There were about 40,000 groups like this in the world, which would mean that there were less than a million people existing in the whole world! More people than that live in Houston right now. They also started to use fire as a tool to drive big game off of cliffs in order to more easily slaughter them. This showed that the H. heidelbergensis were more developed then their previous ancestors, the H. erectus and the H. ergaster.

Characteristics of Neandertal

The physical characteristics of the Neanderthal differ in many subtle ways from our own. Their skull was structured differently, with a dense, overhanging browridge followed by a long, flat skullcap, eventually terminating in a "bulging, bunlike cranium". Their lower jaw was thrust forward to facilitate the use of large, powerful front teeth, they used these teeth for a variety of practical purposes, including but not limited to chewing animal hide to render it more supple or holding pieces of wood so that they could use both hands to carve or chop them. They had broad, flat noses, superimposed on a forward-thrust face structure. This was very important to their survival since they lived in such cold places: the large nasal cavities warmed air before it entered the lungs, while a dense slab of bone kept it away from the brain, and it also prevented them from overheating while running, because sweat would probably freeze in their environment. Their physique also helped them keep warm: they had short extremities and a barrel- chested frame, with lots of extra muscle and bones 10-20 percent heavier than ours. They weighed anywhere up to 225 lbs. Their lifestyle of walking many miles a day while bearing heavy loads lent them massive upper body strength and a handgrip 2-3 times more powerful than ours.

Tools

Oldowan Tools

Oldowan tools are the oldest known tools in history. These stone tools date as far back as 2.5 million years ago.

Acheulean Tools

About 1.6 million years ago, Acheulean tools were the most sophisticated objects on the planet. They were first manufactured by Homo erectus.

Neanderthals

Neanderthals further refined tools. They used a new, advanced technique to make these tools, known as the prepared core method. This method required them to knock the top off of a round rock, thus producing a disk-shaped core. They could then produce 2 or 3 almost identical flakes from this core. These tools were used for attacking large mammals, such as horses and mammoth, which they killed in large, pre-planned hunts. Neanderthal's tools mainly consisted of knives or hand axes.

**Cultural life

The Neanderthal culture was richer than that of their predecessors. Some groups honored particular animals, amassing large collections of their bones and burying them in one pit, covered with a stone slab. Bears were a very popular animal to honor. Also, they took great care of each other if they were injured, healing broken bones and other injuries in each other and feeding and caring for the blind and crippled (the old man of Shanidar).

**Mental development

Neanderthals were the first to recognize and ceremoniously utilize the respectful burial. The body would be laid on a mat of natural materials and then strewn with flowers. The flowers, grape hyacinth, hollyhock,and cornflower, are still used in Iraqi herbal remedies, thus suggesting they were a symbolic medicinal aid for the afterlife. However, they had no interest in art, and never saw the practical use of animal bone as a tool-making material. Also, they never showed interest in traveling anywhereoutside their immediate vicinity. An Excellent source for Neanderthals in general is http://www2.sjs.org/beniretto/Origins/Chapter%202.pdf pages 23-25.

Characteristics of H. sapiens

technology

Technology was the Aurignacians' first major revolution. They were the first people to make tools in order to make other tools. They were able to make long, elongated sharp razor edges, but also as well as small 3/4 inch "micro-flints" for precision work. Aurignacians also made a variety of tools for special uses, from scrapers for cleaning hides to burins for engraving antler bones. This society was know as 'blade and burin'. The tools became more and more common place when these tool-makers developed the technique of annealing, which involved heating the flint up, and therefore making it more workable. This was usually done by putting flint is very warm sand. Another innovation was producing composite tools, which were stone tools glued by tree resin to wooden handles, giving the user a firmer grip.

**blade and burin society

**weapons

**social organization The Aurignacians were the first to use the concept of Shamanism. One person would be selected to communicate with the other cosmos besides theirs. The two sets of cosmos coexisted with each other and the shaman was used to cure the sick, maintain a good relationship with the other world, restore lost harmony, etc. For more information, see pages 23-26 in the Manual.

**dispersed leadership Dispersed Leadership was used by highly egalitarian groups, who had no leaders. Dispersed Leadership recognizes the talents and experience of each person in the group. All the decisions were made together, and there was no sense of privacy, so all the grievances were public and settled without a fight. The notion of private property was alien to the hunter-gatherer. The most helpful source was http://www2.sjs.org/Beniretto/Origins/Chapter%202.pdf page 29, under Development of Social Organization

**cooperation and its effects

**communication/art

**other advances

Explain both the multiregional and diffusionism/ Out of Africa hypotheses

The multiregional hypothesis says that homo sapiens evolved somewhat simultaneously in Africa, Europe, and Asia with some mixing between the regions. This means that present day people from a certain region evolved from the population of Homo erectus that lived in that region thousands of years ago. What supports this is the similarity of some of the anatomical structures of modern humans of a certain region and the Homo erectus that lived in the same region thousands of years ago.

The Out of Africa Hypothesis says that a small group of early humans evolved into Homo sapiens in Africa and that population eventually spread across all of Africa, Asia, and Europe. As they spread, they were so successful that all other hominid species died out. There is mitochondrial evidence for a time of divergence from the common ancestor of all modern humans and it dates back to around 200,000 years ago, making it too young for the Multiregional Hypothesis.

An excellent source for showing the different origin models is http://anthro.palomar.edu/homo2/mod_homo_4.htm

H. sapiens is the only hominid left. Why?

H. sapiens were able to settle in such diverse habitats. Give reasons and rationale.

Id The Aurignacians

ID Gravettians

ID Magdalenians

Natufians

What effect did settling down have on the species?