The Encephalization of Primates: Size Matters
A crucial turning point in Primate history took place 2.6 million years ago when various selective pressures led to the encephalization of Hominins. The ice age quickly approached this time period and thus resulted in a struggle of adaption and survival for many animals on earth. This took a particular impact on early hominins; Hominins during this time lived in Africa and thus were affected by the Ice age in a completely different way. Africa, instead of becoming colder, became much hotter as result of the frozen oceans, which created a dry savannah environment. In addition, many primatologists as well as archeologist agreed that the savannah offered both a dry but stable environment. The need to adapt to the new environment resulted in both the extinction of primate species as well as the encephalization of homimins. The accelerated growth of the hominin brain allowed them to acquire skills that would permit them to adjust to the changing world and some examples of these new adaptations included the use of stone tools. Stone tools are attributed to this era and it can also be inferred that these were used during the incorporation of meat to the hominin diet. Hominins, 2.6 milllion years ago began to consume meat as result of scarce fruits and leaves in their new environment. It is theorized that the stone tools were first used to cut animals apart and extract marrow from their bones, while more sophisticated tools later were used for hunting and making clothes. Although the real explanation for the accelerated brain growth of early hominins is uncertain, most primatologist agree that larger brains are energetically expensive and that their diet contributed to this greatly. Paleontol...
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...fruit and leaves had a substantially bigger rib cage than that of a humans who eat meat. It was also noted that tool use was easier with a narrower rib cage than a wider rib cage and this supports the theory that hominins incorporated meat to their diet (Aiello and Wheeler 1995). As noted, tool use approximately 2.6 (mya) could be liked with the consumption of meat and the expansion in hominin diet would explain smaller gut size. Meat is much easier to digest therefore the body has to work less to process the food and as result it can be concluded that the brain took the extra energy that smaller gut did not use. Overall, the expensive tissue hypothesis claims that the adoption of a high quality diet such as the incorporation of meat explains the reduction of the gut, which reduced the energy intake of the gut and fueled the encaphilazation of the hominin brain.
The evolution of man is constantly in question. While we are reasonably sure that modern humans and primates are both related to the same common ancestor, there is constant debate over what initially caused the two species to split into early hominids and apes. According to some, our longest and most popular theory on the division of man and ape is profoundly wrong. However, those same individuals usually offer an equally controversial theory as a substitute, one that is almost impossible to scientifically test or prove. Both the Savanna Theory and the Aquatic Ape Theory offer solutions to how and why humans evolved into bipedal toolmakers. But with enough questioning, each loses its accountability to rhetorical science.
Humans are not the only species with the ability of making tools. Early on in her research, Jane Goodall observed an older male chimp, she called him David Greybeard. Through her observation of David, she witnessed two forms of the use of tools. The first was the use of grass as a tool to extract termites from their mounds. The second was the making of a tool by stripping the leaves off a twig, modifying it for the same purpose. When Louis Leakey heard this, he wrote her “Now we must redefine tool, redefine man, or except chimpanzees as humans” (Goodall, 2002). There is a definite correlation between man and chimps in this respect. Human culture involves learned behaviors through observation, imitation and practice, the use of tools with chimpanzees show the same ability for learned beh...
It is emphasized that there is little proof to be found in the archaeological record, but we can track hominin dependence on cooked foods, and thus fire, by evolutionary changes in the skeletons of human ancestors. Reasons for making the shift to cooked foods is unknown, but it is hypothesized that the taste of cooked foods was what first turned hominins onto the joys of cooking.
There has been an age long debate to whether or not primates have culture. This is based on the idea that primates may have certain behaviors that our taught rather than already being programmed in their minds biologically. Some would argue that a certain action that a primate does wouldn’t necessarily be something that primate was born knowing; but others would argue that it was something that was something they knew in their subconscious mind. Notable arguments that would be in favor of culture in primates would include their use of tools, how a primate eats, and how they interact; arguments against the theory of culture in primates would proclaim that a primate’s habits are determined biologically and not affected by outside sources.
Throughout situations and research conducted by not only Robert Sapolsky or Jane Goodman, but from many other credited sources, we can blatantly see the, if not identical, similarities between the two species of humans and baboons. The most apparent likewise characteristics of this can be read and documented in Professor Sapolsky’s book, A Primate’s Memoirs. Sapolsky, who spent hundreds if not thousands, of hours studying these Savanna Baboons, sheds a vast insight into ideas of social dominance, mating strategies, instinctual prowess, community settings, hygiene, and reform of an entire generation; many of which can be unknowingly seen directly in the common occurrence of a humans daily life.
It has been believed that culture is unique to humans and no other groups of animals have culture, but recent evidence refutes this ideology. Before getting into the meat of the argument, it is important to first address the issues regarding the ambiguity of the term, “culture.” What is culture? Many scientists may argue that culture is the way of life for a group of individuals, this definition includes the values, beliefs and traditions of the group (Sapolsky, 2006). Other scientists may argue that culture is the transmission of habits and information by social means (Sapolsky, 2006). Despite the different specifics of what culture is, almost all scientists would agree that culture is transmitted socially through social learning that promotes the transfer of information between members in a group (Boesch and Tomasello, 1998). Based on these notions of culture, it can be justifiably stated that primates have culture. Primates exhibit food preparation techniques, use of tools, communication skills, and most importantly, behaviors of social learning. An exemplar of primates’ capabilities for culture is Koko, the lowland gorilla. Koko, in captivity, was able to learn American sign language, demonstrate self-awareness and the ability to deceive.
The ancestral lines of Neanderthals and modern humans is split roughly about 800,000 years ago, making them our closest relatives in the hominid ancestry. Neanderthals inhabited Europe and parts of the Western Asia before going extinct around 30,000 years ago. Neanderthals made and used a range of tools, they were able to control fire, make and wore clothing, were very skilled hunters of large animals however also ate plant foods, they lived in shelters, and occasionally made symbolic or ornamental objects, which no previous hominid species, had ever practiced this representative and complex conduct. Over this essay we will be covering some elemental information on Neanderthals, their differences and similarities anatomically with modern humans, along with their differences in behavior, and finally giving some possible implications for the timing of the development of culture.
Monkey see, monkey do. Apes have always been thought to have an increased level of intelligence. Over the years, researchers have attempted to understand the degree of intelligence these primates possess. However, it is essential to understand the definition of intelligence in order to determine the amount of intelligence primates have. Intelligence is the capability of obtaining knowledge and being able to utilize it in everyday situations. There are many hypotheses that focus on the evolution of intelligence in primates that view a number of factors including brain size and modernism. Primate intelligence has been a topic of interest to many because it will allow us to further understand the close relationship between humans and primates. Additionally, we will be able to understand the difference between human and primate cognition. Some studies suggest that the human and primate brains possess many similarities. This demonstrates why primates tend to respond to stimuli in a manner that is closely related to humans. Researchers have conducted a number of studies in an effort to understand primate cognition.
Bindon, Jim 2004 Fossil Hominids. ANT 270 Notes. http://www.as.ua.edu/ant/bindon/ant270/lectures/ hominids1.pdf Delson, Eric 1981
The idea that early hominids were powerful players in the ancient is slowly slipping away. Evidence is emerging that our ancestors were not great hunters, but scavengers that roamed the savanna looking for leftovers. Pat Shipman, discusses how it would be possible for early hominids to survive as strangers and how this method of cultivation affected human evolution. Shipman, uses the marks that stone tools, and teeth would make on the bones of prey animals as evidence for her hypothesis. She theorizes that early hominids weren't mighty hunter, but cunning scavengers.
“The scientific study of how humans developed did not begin until the 1800s in Europe. Until that time, people relied on religious explanations of how humans came into existence. Starting in the 1500s a scientific revolution began to sweep Europe. Thinkers started using scientific methods and experiments to try to better understand the world and the creatures living in it. Eventually these methods were turned to the question of human origins” (The Nature Of Human Origins, 1). Earth made it possible for species to change over time because Ancient Earth provides ability to plenty of time.The Homo Sapien a is very complex creature. The species started off very simple by living in caves and surviving with little food and then later evolved into a species that were able to do many more complex things. The first species was Sahelanthropus tchadensis They were one of the most simple humans in that time period and on. They had very small skulls compared to Homo Sapiens today and their motor skills were just the same. We have evolved and changed for the better both mentally and physically. The Evolution of Homo Sapiens started off simple, such as the Neanderthals, and now we are the most advanced species to ever walk the planet so far.
Approximately two million years, exceedingly evolved Australopithecines made their priority to impact their environment. They made tools and started to use resources. The age of Homo Habilis has begun. They are the earliest known members of the Homo genus. They were found in Africa. Homo Habilis brains were 50% larger than Australopithecus, they were taller, hairless face, and flatter nostrils. They became omnivores. They were the first to discover that meat was edible. Scavenging for dead meat was added to their diets. This is known because of their teeth. Homo Habilis had developed mature incisors, which are used for shredding chunks of meat. Wisdom teeth were also developed for chewing meat. The most fundamental development in Homo Habilis is language. Containing larger cerebral cortex than their ancestors, they developed the abilities in thinking, reasoning, and memory. They also hunted, which was a group activity because it requires precision, accuracy, planning, and silence. As a result, they probably developed hand signals and facial expressions which granted meaning for use in hunting parties; this could have been the first symbolic communication. As the Homo Habilis grasped more of this communications the signals became more complex. As a result, hands signals were developed to represent abstract concepts like good or evil. Furthermore, the hand signals organized and unified with sounds to produce a simplistic form of language. This form of communication along with tools and resources have become the foundations of an advanced culture. Homo Habilis were unendingly bipedal, thus, losing their ability to climb. Their brow ridge and the beginnings of the chin were gone. Homo Habilis were about four feet fall on average. The most complex toll made by them was the chopper, which later advanced into the axe. Homo Habilis ruled over Africa until about 1.6 million years, when Homo Erectus surfaced,
Paleolithic age presents the era when key human adaptations evolved in response to a variety of environmental changes experienced at the time. This period of human evolution coincided with change within the surrounding of man. Such included cooling, drying and unpredictable climatic patterns over the time. This increased amount of variability in environmental conditions raised the level of uncertainty and instability in their respective terms of survival, necessitated the man to adopt new habits to increase adaptability to the new and changing surroundings. The evolved structures and behaviors led to specialization to enable coping with changing and unpredictable conditions.
Teaford, Mark F. "Diet and the Evolution of the Earliest Human Ancestors." Proceedings of the National Academy of Sciences. 5 Oct. 2000. Web. 19 Nov. 2015. .
The increase in brain size may be related to changes in hominine behavior (See figure 3). The third major trend in hominine development is the gradual decrease in the size of the face and teeth. According to the Microsoft Encarta Encyclopedia ’98, the fossil evidence for direct ancestors of modern humans is divided into the category Australopithecus and Homo, and begins about 5 million years ago (See figure 1). Between 7 and 20 million years ago, primitive apelike animals were widely distributed on the African and, later, on the Eurasian continents (See figure 2). Although many fossil bones and teeth have been found, the way of life of these creatures, and their evolutionary relationships to the living apes and humans, remain matters of active discussion among scientists.