Human biological and cultural evolution 2


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  • This series of lectures examines the biological capacity for human culture, how we fit into the animal kingdom, and how we came to be what we are as the genes Homo and the species sapiens. We are the only one of that species, which means that we can interbreed with any other human population in the world. Our humanlike species disappeared from the planet 30,000 years ago.
  • Even though culture is acquired by learning, our capacity for culture is in our biology. We don’t inherit specific languages, such as English, or Spanish, or Swahili. But our capacity to speak a language is the product of our genetics and biology. Four culture specific areas are rooted in our biological selves: (a) ability to think; (b) ability to speak or otherwise use a language (such as signing); (c) ability to make and use tools; and (d) our ability to walk on two feet, which enables us to do other things. If anthropology is the science of humankind, then we need to know something about our biology, our anatomy.
  • In this unit, we look at how we fit into the scheme of biological things known as taxonomy. We then will have a look at our human anatomy and how we compare with the chimps and other great apes. The focus will be on the four major topics we just identified: thinking, language, tool use, and our abilities that bipedalism allow us. We will see when these abilities came to be among our fossil ancestors. Then we will have a look at the behavior of our closet cousins—nonhuman primates such as chimps—to see if they provide us some insight into our own behaviors.
  • We start with the questions: how do we fit in with the rest of the animal kingdom? The answer lies in taxonomy: the hierarchical systematic classification of all living things. We start with the broadest category: the five kingdoms, one of which is the animal. Then we go down to the more specific categories: phylum, then class, then order, then family. The lowest (most specific categories) are the genus, then the species and, if needed, varieties or subspecies. Each of these categories—general or specific—are known as taxon (taxa in the plural).
  • We use a system called binomial nomenclature, that is, a naming system of two names, to identify specific types of animals In our case, our genus is Homo and our species is sapiens. Homo means “human,” and sapiens means “wise.” If we need a subtype, or variety, we add a second sapiens to the name. Note that all parts of the name are italicized, that the genus name is capitalized, and that the species is lowercased. The variety is also lowercased if we need it. (Experts don’t agree on whether there are two varieties or only one. More later.)
  • As I said, taxonomy starts with the broadest categories or taxa, and go down to increasingly narrow taxa. The broadest taxa are the kingdoms, of which there are five. We belong to the kingdom Animalia (animals) because we ingest food and are mobile—we can move around. We cannot produce our own food, which the plant kingdom can. Next, we belong to the phylum Chordata because we have a spinal cord; animals like octopi, squid, and starfish don’t have spinal cords. We then belong to the subphylum vertebrata because our spinal cords are protected by vertebrae, or our segmented backbone. Next, we belong to the class mamalia (mammals) because we have hair, our females have mammary glands that secrete milk, and we are warm-blooded at a constant temperature of 98.6 degrees Fahrenheit0.
  • Now we are getting closer to home. We belong to the order Primata; we are primates in other words. There are several features of primates. First, we have larger brains relative to our bodies. We have one over the whales, because their brains are 20 times larger than ours their bodies are 200 times the size of ours. If you do the math, we have a larger brain-body ratio than whales. Second, we have stereoscopic vision. That means our eyes are angled forward in the same direction. That enables us to perceive depth, very handy if you live in the trees and you have to jump from one branch to another. We have flexible digits in our fingers also toes among monkeys and apes), handy for grabbing onto things, whether tree branches or tools. Finally, we are sociable beings. They not only move in groups, they also have complex social relations, reflected in grooming, dominance hierarchies, and even mother-child relations. More on that later.
  • The next major taxa are two suborders. The Prosimians (Prosimii, or “before simians”) look like squirrels, raccoons—anything but manlike beings) They are the lemurs, the tarsiers, the bush babies, found most in Madagascar and parts of Africa and India). The anthropoids (Anthropoidea, or “manlike”) look like men. The suffix –oid means “something like.”} These are the New World monkeys, the Old World monkeys, and the apes. They can stand upright—sort of—their hands are like hours, and their feet are somewhat like ours.
  • Superfamily Hominoidea is next: it means “humanlike” (remember that –oid ending, meaning “something like”) They include the apes and humans. Their brains are larger than the monkeys, they have no tails, and their body size is larger. They appear even larger than the humans.
  • At the level of the family, the old and new taxonomies have created a lot of confusion. We’ll look at the old system first, then the new in the next panel. In the old system, we have three families. The first family is Hylobatidae, or lesser apes, including several small species of gibbons and siamangs, all in Southeast Asia. The second family is Pongidae, comprising the great apes Orangutans (Southeast Asia) and the African gorillas, chimpanzees, and bonobos (or “pygmy chimpanzees). The third family, Hominidae, comprises the fully bipedal modern humans and other (now extinct) members of the genus Homo and earlier genera (plural of genus) called Australopithecus (southern ape man).
  • The new taxonomy has thrown a monkey wrench into the taxonomy of humans and apes. We still have the old superfamily, Hominoidea. At the family level is where the changes are. The lesser apes (gibbons and siamangs) remain unchanged; they’re still called Hylobatidae. But the family Pongidae now has only one member, the orangutans (genus Pongo). In the family Hominidae, we move over to accommodate the African apes. Humans, gorillas, chimps, and bonobos all now belong to one happy family. To separate those, we have new subfamiles: Gorillinae for the goriilas, Paninae for the chimps and bonobos; and Homininae for the humans, us modern Homo sapiens and the fossil Homo and Australopithecus. What did I say about a monkey wrench?
  • Why the monkey wrench? Why can’t taxonomists leave well enough alone? The culprit behind the confusion is that recent genetic analyses show that the human genetic makeup isn’t all that difference from the chimps and bonobos; their genome (sum total of all genes) is 99.5% different from ours. From gorillas, the variation is about 99%. On the other hand, human and orangutan genomes vary by about 93% to 95%, justifying a separate family for orangutans.
  • We start this section with the basics of anatomy—our own and the chimps. Why do we need to know this. Again, we didn’t get our ability from the gods on high but from out own biological make-up. Our brains are the seat of thinking, our language, and even our tool use. Have you ever heard of making tools without planning ahead? I haven’t. And there is one other thing about human populations: our ability to stand and walk on two feet.
  • We start with the basics. Our human skeleton. Use your handouts to learn about the bones of the human skeleton.
  • The human brain is where it all begins. This chart gives you the major parts of the brain. The frontal lobe is the seat of our ability to think and to plan ahead. Through the frontal lobe, we can decide what kind of stone tool to knap, how to hunt game, the best way to plant a gardens, and hundreds of other tasks. The primary motor cortex enables us to do plenty, as the next slide will show. The parietal lobe governs the senses of touch, the occipital lobe allows the sense of sight, and the temporal lobe governs the sense of hearing. Then there’s the sense of smell—that is the job of the olfactory bulb just underneath the frontal lobe.
  • This is a cross section of the motor cortex. As you can see, much of the lower part of the motor cortex is related to the mouth: the tongue, the lips, the face, even the vocal cords. They are all related to eating—but they are also related to speech. Then the upper part of the motor cortex is related to our ability to manipulate objects with our hands. Much of the cortex is devoted to the fingers. This manipulative ability is tied in with our tool-making ability and to its use. The topmost part of the cortex is related to our feet and legs. How does that relate to our walking ability?
  • This graphic shows the parts of the brain specifically connected with language. Broca’s area is the part that processes speech. Note that it is in the area of the motor strip that coordinates the mouth and tongue. Wernicke’s area processes the reception of speech; note that it is in the temporal lobe, the center of hearing. The arcuate fasciculus is a bundle of nerves that connects Broca’s and Wernicke’s area, giving the speaker feedback on what he/she is saying or should say. The angular gyrus is vital to language; it coordinates all five senses, so that you can translate what you see or touch or smell into sound, which is what language is all about. And if you rely on signing, it translates everything into sight. Signing could not exist without this intermodal capacity.
  • This graphic shows the parts of the brain specifically connected with language. Broca’s area is the part that processes speech. Note that it is in the area of the motor strip that coordinates the mouth and tongue. Wernicke’s area processes the reception of speech; note that it is in the temporal lobe, the center of hearing. The arcuate fasciculus is a bundle of nerves that connects Broca’s and Wernicke’s area, giving the speaker feedback on what he/she is saying or should say. The angular gyrus is vital to language; it coordinates all five senses, so that you can translate what you see or touch or smell into sound, which is what language is all about. And if you rely on signing, it translates everything into sight. Signing could not exist without this intermodal capacity.
  • This graphic shows the parts of the brain specifically connected with language. Broca’s area is the part that processes speech. Note that it is in the area of the motor strip that coordinates the mouth and tongue. Wernicke’s area processes the reception of speech; note that it is in the temporal lobe, the center of hearing. The arcuate fasciculus is a bundle of nerves that connects Broca’s and Wernicke’s area, giving the speaker feedback on what he/she is saying or should say. The angular gyrus is vital to language; it coordinates all five senses, so that you can translate what you see or touch or smell into sound, which is what language is all about. And if you rely on signing, it translates everything into sight. Signing could not exist without this intermodal capacity.
  • A little comick relief, courtesy of Geico. (Actually, courtesy of Gary Larson.)
  • To understand how humans might have communicated in the past, it helps to take some clues from skull remain. These are parts of the skill. Note that the bones are named after the parts of the brain they cover—the frontal bone covers the frontal lobe, and the same goes for the parietal bone, the occipital bone, and the temporal bone (your temple, remember). Other key terms to know are the mandible (lower jaw), the maxilla (the upper jaw), and the zygomatic arch (cheek one).
  • Here is a comparison of a human skull with an ape skull. Notice that the chimp has a heavy brow ridge (supraorbital torus) and a sloping forehead. We have a high forehead and no brow ridge. Guess which specimen has more of a frontal lobe? You guessed it—we do. Notice also that the chimp has more of a forward projecting or jutting jaw than the human. This jutting is known as prognathism, which is one feature we find later in fossil hominins. The teeth are different, too. The chimp has a large canine, so large that a gap is present for the canine to fit into the opposite jaw. This gap is known as a diastema, and we find it among the earliest fossil hominins.
  • The brain structure also gives us a clue to the probable evolution of human kind. Chimps, as we will see, have some capacity for language (but not for speech). Humans has a Broca’s area, but chimps have none. Instead, they have to settle for Brodman’s area, where chimp calls originate. Likewise, chimps have no Werkicke’s area; the planum temporale is the site where chimps receive calls in the wild. Finally, notice the brain capacity. First, the chimp brain is smaller than the human one, averaging 400 cubic centimeters (cc) as compared to our average of 1400 cc. The structure is different as well. Chimps clearly have a smaller, more confined frontal lobe than we do. The sloping forehead and the heavy brow ridge does the chimp no favor.
  • So what does all this mean? It means that our capacity for culture is facilitated by a larger brain and a well-developed frontal lobe, compared with the chimp’s. It means that our language areas, especially speech generation and speech reception, are better developed, thanks to Broca’s and Wernicke’s areas, which the chimps lack. We have a better developed motor strip as compared with the chimp’s
  • But the story does not end with the brain or skulls. We need to find out other pieces of evidence about human evolution. One is the comparison of our dentition, or row and structure of our teeth as compared to the chimps. Notice from the diagram that the teeth are in a nicely arranged dental arc. Our dentition is basically the same as chimps and all Old World apes and monkeys. For each jaw, we have four incisors, which cut the food; two canines (doglike teeth), which pierce the food; four premolars, for light grinding, and six molars for heavy grinding. The dental formula for one quadrant (half a jaw, upper or lower) is, which you will also find for all Old World monkeys and apes.
  • The arrangement of teeth in the jaw is known as a dental arcade. Notice that the human jaw is shaped like an arc. In contrast, the back teeth (premolars and molars) of the ape are parallel with each other. These teeth are much larger than the human back teeth. Notice also that our canines are small; the ape’s canines are large. You may also notice the gap in front of each canine that allows the canine of the opposite jaw to fit in. That is the diastema. Finally, the ape’s jaw does not converge until you reach the front. The front teeth angle outward, almost horizontal, whereas the human incisors are vertical.
  • Another development is the highly flexible human hand; its thumb and finger enable human to make fine manipulation, essential for the tools we are able to make and use. The fingers are also straight and the thumb is longer than other primate species. Get to know the bones: carpals are the wrist bones (any of you have tunnel carpal syndrome?}; the hand bones are called metacarpals, and the fingers are known as phalanges.
  • Here’s one reason why we are better at using tools than the chimps: our thumbs are longer and have a better reach in front of the palm of our hand. The thumb of the orangutan the chimp, and the gorilla (pictured in the order mentioned) are much shorter than ours. Their fingers are also curved (good for using in climbing trees); ours are straight. That all means that we can make a finer grip than they can.
  • This picture compares the power grip, in which the fingers and the thumb wrap around the object, with the precision grip, in which the object is held with the thumb and forefingers. Both apes and humans can make a strong power grip, but humans, thanks to a longer thumb and flexible straight finger, make a finer precision grip than the apes whose hands are depicted in the last slide. Apes can make and use tools, but they will never build a finely crafted stone tool, let along construct a computer.
  • Remember the song ‘Locomotion”? Probably not. That goes back to the 1950. Both chimps and humans do the locomotion, but in different ways. Chimps are essentially quadrupedal, but occasionally move about on two feet some of the time. Humans are obligate bipedal; they have to walk on two feet; they cannot move on four feet. Above, here is a chimp knuckle walking about on all fours. It is actually using its hind feet. In comparison the best we can do is go about on our hands and knees. Try waling with your back feet, and you’re either a yogi (yogini) or are about to rip your pants.
  • These skeletons show the differences between chimp and human locomotion. Again, notice the chimp’s knuckle walking. Notice too, the differences in skeleton. The chimp has an opposable toe; we have none. Instead, our big toe is aligned with our other toes, and we have an arch—two arches—whereas the chimp has only one, and not very prominent at that. We have an S-shaped vertebral column (backbone). The chimp has a bow-shaped backbone. If you look closely, our spinal cord will go into the base of the skull. The chimp’s spinal cord goes into the back of the skull. Finally, our pelvis is short and bowl shaped. The chimp’s pelvis is long and narrow, better fit for a quaduped.
  • What’s the big deal about bipedalism. For one thing, we can get around faster than if we had to go on all fours. For another, our hads are free to carry babies, loads, spears, tools—in fact, just about anything (or anybody). Our hands are free to make and use tools. Can you imagine how long it would take to build a house if you had to drop everything to get around? Other hypotheses suggest we became bipedal back in the African savanna (tropical grasslands) to peer over the tall grass to track herds of animals or to avoid lions and leopards. That issue is under debate.
  • Here is a graphic comparing the chimp’s vertebral column and pelvis with those of the human. Again, our vertebral columns is S shaped, and the size of the vertebrae increase from the cervical vertebrae (of the neck) to the thoracic vertebrae (near the ribs) to the lumbar vertebrae (lower back) reflecting the load the body has to carry from the top downward. The vertebrae of the chimp don’t vary in size all that much, and they can get away with the bow shaped of their backbone. As for the pelvis, it is short and bowl-shaped, providing attachment for the muscles of the gluteus maximus to keep its owner upright. The chimp pelvis is long, allowing it to move on all fours rapidly.
  • Here is the front view of the pelvis of chimp and human; again the ilium, or blade of the upper pelvis, of the chimp is longer and flatter than the ilium of the human, which is bowl shaped consistent with bipedalism. The lower graphic compares the angle of the chimp femur (thighbone) with that of the human. The human thighbone angles inward from the pelvis to the knee (the kneecap is the patella). This affords greater support to the body, whose weight is borne partly by the femur and the lower leg. The femur of the chimp, in contrast, is straight up and down. When it stands and walks bipedally, the entire weight is borne by the lower trunk.
  • These graphics compare the human with the chimp foot. Notice that the chimp has an opposable toe, suitable for grasping objects or branches of trees, but not for bipedal walking. All the toes of the human foot are aligned and form a double arch. The tarsals (ankle bones) of the human are larger than that of the chimp, and they form the back of the longitudinal arch, which runs from the calcaneus heelbone to the first metatarsal (foot bone) The foot also forms a transverse arch from the fifth metatarsal to the instep.
  • These graphics depict the longitudinal arch of the foot and, by inference, the transverse. Note that the top graphic shows that the outer foot touches the surface while the lower one depicts the instep in the inner part of the foot.
  • With the prolific remains of fossil hominins, including Lucy and her kind (Australopithecus afarensis), the record of human biological and cultural evolution is well established. We start with an intellectual and cultural history of the transition from creationist to evolutionary thought, then look at the record of fossil hominins and, after the first was made, their tools.
  • This section looks at the history and the process of biological evolution. It involves two processes: change in a living thing created by the genetic change of that organization and survival through the pressures of natural selection. Populations can also change by migration (ene flow) and by genetic drift, when an organism breeds enough offspring to effect change in small populations, which may eventallly grow.
  • Prior to the enlightenment in the 18th century, theology dominated the model of the universe. From medieval times, the Great Chain of Being dominated beliefs about God, Man, and Nature. All living thing had their place. Humans were the most perfect beings in creation. Yet not only were angel above man in this hierarchy, but so were demons, the angels of darkness.
  • Catastrophism, the idea of sudden creation and destruction, was the model explaining natural changes. Man was created by God in six days. Woman originated in Adam’s rib. Not that catastrophic change did not occurs. An asteroid struck the planet 65 million years ago, which led to mass extinction and nearly ended all life.
  • Research into natural phenomena, such as it was, followed the model of catastrophic change. Using biblical genealogies and astronomic processes, Archbishop James Ussher set the date of humankind’s creation at noon, October 23, 4004 BCE. The inventor of taxonomy, Carl Linné (also known as Carolus Linnaeus), developed his classification of life forms on their similarities and differences, a process continued in use today. He based his taxonomy on the Great Chain of Being model.
  • In this belief, the First Couple lived in the part of Iraq where the Garden of Eden was located, at the end of the Tigris-Euphrates confluence in the south.
  • According to biblical myth, the First Couple were told by God they may eat the fruit of every tree freely—except for the Tree of Knowledge of Good and Evil. (A commentator, Alan Watts, Anglican cleric turned Zen master, calls this a mistranslation from the Greek. The phrase was “The Tree of Knowledge of the Useful and the Useless” Try the implications of that expression on for size.)
  • But temptation overcame Eve. Thanks to the devil in the form of a snake, she eats the fruit , then tempts Adam also to eat it. God confronts the couple, and carries out the punishment of expulsion.
  • Expelled by an angel bearing a sword of fire (and ashamed by their nakedness), the couple ends their days living by the sweat of their brow. Woman must bear the pain of childbirth. (Or was Adam condemn to engage only in activity that is useful, as Watts would have it? Now here’s an ethnohistorical project for you!)
  • Of course, here’s a slight update of the Garden of Eden story—located in Iraq, of course, and caught (gasp) with a (near) naked woman not his wife. Now will God say anything to the current president about Afghanistan. . .?
  • One of the first assumptions underlying biological evolution is the length of time it takes for evolutionary change to occurs. If there is anything to this model, then the process had to take longer than 6,000 years. Uniformitarian is the assumption that all geological processes—erosion, tectonic plate movement, silt deposits from yearly floods—have to occur at the same rate as they do now, in the absence of reason to believe the contrary. That meant the geological processes took millions, perhaps billions of years, to occur.
  • The geologist Charles Lyell, first came up with the principles of uniformitarianism, three of which hold up today: constancy of the rate of geological process, the use of stratigraphy to reconstruct the history of the earth, and the immense amount of time to effect change in the landscape. Current calculation place estimates of the age of the earth at 4.5 billion years.
  • The basic unit of life is the species, or a population of individual life forms capable of reproducing viable offspring. Natural selection is the differential reproductive success of individual within a species though successful adaptation to an environment. This tongue twister emphasizes that some populations adapt better to a given environment than other populations, but it does not necessarily imply that the less successful populations will become extinct. Darwin never used the phrase “survival of the fittest”; the founder of British sociology, Herbert Spencer, coined that phrase.
  • Charles Darwin, one of the scientists to come up with the theory of natural selection, came up with the idea from observing artificial selection—the selective breeding of domesticated animals. He observe the breeding of pigeons, racing horses (including thoroughbreds), and show dogs. If man could do it, why not nature. His observations of finches on Galapagos Island led him to conclude that nature did select different species after all. After years of dithering about publishing his findings, because he feared the reaction of the church to his findings, he finally published his conclusions in The Origins of Species in 1859. (By the way, he was born on the same date as Abraham Lincoln: February 12, 1809).
  • After taking specimens of finches, Darwin came to the conclusion that the 13 reproductive isolated finches adapted to different habitations. Some had variously shaped beaks that suited them to eat seeds, insects (including the woodpecker finch who got their meals from tree barks; cactus finches, mangrove finches, and ground finches). One finch was vegetarian. They were all different species and they adapted successfully to 13 ecological niches. This diagram shows the genealogy of the 13 finches from one ancestor from the South American mainland.
  • Darwin illustrated natural selection with different colored moths in different environments. Cities like Manchester were the home of steel manufacture, which requires large quantities of coal. Coal soot covered the cities and darkened everything it landed on. While light-winged moths lit on darkened trees and shrubbery were picked off by birds who saw them easily, dark-wing moths escaped the birds’ attention and so survived. In the countryside, it was the dark-wing moths that were picked off, while the light-winged moths escaped that fate. By the way, how many moths are there on this tree. If two, where is the second one.
  • Darwin determined the outcome of a process called natural selection, but the title of his book was a misnomer. He did not determine how species originated in the first place. It was up to an Austrian monk, Gregor Mendel, to come up with a partial answer in his experiments with peas and their characteristics.
  • Darwin could not have predicted how species proliferate in the first place. Gregor Mendel, an Austrian monk, found that the inheritance of physical traits are governed by what eventually would be called genes. They are the genetic material that determine who and what we are. Genotypes are the genetic make up of a particular trait of any lifeform. Sometimes they appear in physical form, called phenotypes. There are several variations of these genes, called alleles. They are always paired, and any two alleles can be matched at any one time.
  • Then the parents mate, each parent contributes half their alleles to their offspring. One trait may appear as a phenotype and mask the other; the allele of such a trait is called dominant, while the allele that is masked is called recessive. Some pairs may combine to produce a blended trait; they are said to be codominant. A new species may occur if a gene mutates. This process requires a body of knowledge about molecular biology, about DNA and how it works, how proteins are synthesized, and other topics. All these are beyond the scope of this course. .
  • Fossil hominins and their tools don’t come in neat packages, but in fragments scattered throughout a site. Lucy (Australopithecus afarensis) was a lucky find, partly because it was complete for a 3.7 million year skeleton and the fragments were all in the same general location. Most finds come in teeth, bone fragments, and not all necessarily in one place. Even Lucy had about 40% of her bones left, and her skull was gone. That set research back about 10 year until another skull—also in fragments—was found. Tools are equally problematical. How do we know they were flaked by man—or by nature?
  • We start with the earlier hominins. This panel summarizes the main fossil specimens in natural history. The first set are Australopithecus (which means southern ape-man) and Paranthropus. They are both Australopithecines, except that one (Australopithecus) are light-boned and the other (Paranthropus) are more robust, or heavier boned. The first tool makers and users are Homo habilis; from then on, later species of Homo continue to make and refine their tools.
  • This panel provides a refresher of the end points of human evolution, previously described
  • This panel provides a refresher on the end points of bipedality.
  • One of the major trends in hominid evolution is encephalization, or the long-term trend toward larger brain sizes. Cranial capacity refers to the volume of the skull measured from the inside. Cubic centimeters (cc) is the measure of volume, using the metric system. Some paleoanthropologists use the term milliliters (ml) which means the same thing. Brain size is not the only indicator of capacity for culture; the structure of the brain also has to be considered. Most recently, another species, Ardipithecus ramidus was revealed to the world on October 2, 2009, in 11 articles that appeared in the journal Science.
  • Until now, Lucy was thought to have a more complete skeleton than her predecessors. Lucy did allow us to know much more about her species than before the 1970s In this panel, the recovered fragments of Lucy (left) are colored in red; the fragments in white are reconstructed from what we know about human anatomy. The differences between Lucy and ourselves are listed above. How about the similarities. Hint: note her pelvis, her feet, and her S-shaped vertebral column for starters. Also, bipedalism was thought to be the product of living in the savanna plains. Now, we’re not so sure—Ardipithecus, also a biped, but with opposable toes, lived in a forested environment. The whole evolutionary scheme accepted for decades now needs to be rethought.
  • This specimen was reconstructed by 47 different specialists of disciplines ranging from paleoanthropologists to ecologists to anatomists of various sorts to an electronics artist with experience in Hollywood. Talk about a team project. Changes in the evolutionary model include the idea that not all hominins are bipeds, that bipedality is no longer distinctly associated with a tropical grassland environment, and that we will have to rethink the evolutionary branching of hominins from other hominoids (i.e. apes).
  • Here is a point-by-point comparison between Ardipithecus ramidus and other fossil hominins.
  • Gary Larson’s humerus (oops, humorous) take on the first hominin biped.
  • This panel compares the skulls of Australopithecus africanus, a gracile hominin occurring in South Africa, and the robust Paranthropus boisei, one discovered in the Olduvai Gorge of East Africa. Note that the robust form has much larger jaws and thicker cheekbones than its gracile cousin. It also has a sagittal crest, the bony ridge that run the length of the skull cap from font to back. These all form attachments for the muscles it needed to chew the tough roots and leaves that it lived on. This was the first known vegetarian, or vegan if you like. A. africanus also has a prognathous jaw; the jaw is less so for P boisei.
  • It is with the first Homo—Homo habilis—that that we find the first direct evidence of tool use. (A garhi is associated with tools, but association does not mean he actually made them.) H. habilis, which means “handyman,” manufactured the first tools belonging to the Oldowan tradition, named after the Olduvai Gorge in the Great Rift of East Africa. These were mostly pebbles, called cores, from which he knocked off flakes (chips of stone). Both cores and flakes were fashioned into tools. Some served as cutting or scraping tools with sharp edges; other might be used as hammers. At that point, they were not hunters but most likely scavengers. Stones used for tools are typically crystalline; they have a crystal-like structure so that they can be fractured predictably.
  • The next major species was Homo erectus, which had a much larger cranial capacity than H. habilis: an average of 1000 cc, as compared to 440 cc, of Lucy and 680 cc. of H. habilis. The main differences between H. erectus and modern H. sapiens are in the skulls. H. erectus skulls are smaller (human skulls average 1400 cc.), have an occipital bun in the back (see top illustration), and a prognathous jaw. Their brow ridges are still prominent, and the forehead still slopes backward. Finally, there is no chin; the jaws are reinforced by a bony projection inside the jaw called a simian shelf. Nevertheless, an artist’s conception (lower left) suggests that H. erectus is very similar to H. sapiens.
  • Apart from the skull, the postcranial skeleton (skeleton below the skull; the term applies to all mammals) of H. erectus is almost identical to that of H. sapiens. The arms are about the length of H. sapiens, and the pelvis, vertebral column, femur, and lower leg bones are almost identical to those of modern human. The so0called Turkana Boy (pictured) is another rare fully intact skeleton; this specimen was found to the west of Lake Turkana, Kenya. Because his skull is thinner than other specimens, he is often called Homo ergaster (“workman,” because of the tools with which he is associated, but not all paleoanthropologists agree.
  • The Oldowan tradition, associated with Homo habilis, comprise choppers and flake tools, including scrapers and other sharp edged tools. Usually, four or five blows with a hammerstone are sufficient (see text, pp. 25-26.). The Acheulean tradition is characterized by a symmetrical handaxe that requires much retouching using a soft hammer (bone, antler) or pressure with a chisel or other tool. The edge is sharp all the way around, and can be used for chopping, piercing, or cutting, earning it the name “Swiss Army knife). This handaxe is associated with Homo erectus, but it has been found only in Africa, Europe, and West Asia, not in China or Southeast Asia. Both the Oldowan and the Acheulean are classified as part of the Lower Paleolithic (“Old Stone Age”}.
  • Later hominins begin to look more and more like ourselves. Homo heidelbergensis is an ill defined species whose populations vary considerably. Brow ridges are reduced, prognathism is less pronounced and for some are nonexistent. And brain sizes are within range of modern humans, averaging roughly 1200 cc. As the artist’s conception suggests, some paleoanthropologist would classify these hominin populations as “archaic Homo sapiens.”
  • Associated with H. heidelbergensis is the Levallois tradition, in which the lump of stone is shaped into a prepared core (sometimes called tortoise cores because they look like tortoise shells). They are not tools in and of themselves. The sides of the stone are first knapped, then the top. Then, with a single blow, the first flake is knocked off. Four or five flakes are knapped in this way The flakes are then shaped to the desired tool—as projectile points (arrow heads or spear heads), knives, scrapers, or other objects. This is the first tool of the Middle Paleolithic.
  • Neanderthals probably have received the most attention of early hominins. Discovered in 1856 at a limestone quarry in the Neander Valley (hence Neander Thal in the old German spelling) near Düsseldorf, Germany, Neanderthals have been stereotyped as brutish, dull creatures who looked a lot like the cartoon character Alley Oop. This stereotype came from a arthritic male of about 40 years. To be sure, the Neanderthal and human skulls show significant differences: “classic” Neanderthal skulls have an occipital bun, sloping forehead, prognathism in the lower face, and reduced or no chin. One artist’s conception of a Neanderthal downplays the difference between the two species—if they are two separate species, that is.
  • A comparison of the postcranial skeletons of Neanderthals and humans show the same basic structures, but differences in thickness of bone (see illustration). Generally, the features reflect the cold climate that Neanderthals lived in during the Pleistocene ice age. These have raised a storm of controversy among paleoantropologists. Are the differences significant? After all, Australian aborigines have heavy brow ridges and prognathism, yet they have interbred with Anglo Australian for the past century producing viable offspring—and so belong to the same species. Similar issues have been raised, and whether humans could have interbred with Neanderthals is likely to be argued or a long time.
  • Neanderthals were adept tool makers. The Mousterian, associated with Neanderthals, include handaxes, scrapers, projectile points, knives, and others. Francois Bordes identifies 62 types. These belong to the Middle Paleolithic They were also capable of making blades (flakes at least twice as long as they are wide), which comprise the Châtelperronian, the first part of the Upper Paleolithic.
  • With the Upper Paleolithic period, we encounter the first period whose tools are distinctly human. Stone tool types become more and more specialized, and more finely made. Arrowheads appear for the first time, as do the bow and arrow. Tools are made of bone, antler, and ivory in addition to stone. Non-utilitarian objects make their appearance as well: wall murals in over a hundred caves in southern France and northeastern Spain, Venus statuettes in Western Europe, and ornaments of every description. Homo sapiens has arrived.
  • The human journey that began with unknown fossil apes and hominins finally arrive at the modern era. We have seen how humans have picked up an ability to think and plan ahead, We have seen how—at a time still unknown to us—we acquired the capacity for language and for other aspect of culture. We acquired the ability to use tools and to walk bipedally. We’ve inferred how all this came along comparing ourselves with our closest nonhuman primate cousins and using this comparison to infer the anatomy of our fossil ancestors.
  • And now our work is cut out for us. For the next period of time, we will have a look at human language. We will see the different ways peoples of the world make a living. We will discuss sex and gender marriage, the family, and the formation of larger groups beyond the family. Cross-cultural economics will be looked at and compared, and the modes of social control, with government and without, will be examined. The intangibles of culture, namely psychology and variations of the supernatural, will be covered as well. And, at last, the impact of a globalizing system, political and economic, on traditional cultures will be discussed, together with what Third World peoples, have done about the invasions these forces unleashed.
  • Human biological and cultural evolution 2

    1. 1. Human Biological and Cultural Evolution Cultural Anthropology
    2. 2. Culture in Evolutionary Perspective To understand culture, we need to:  (1) Know our biological capacity for culture  (2) How we fit into the animal kingdom  (3) How we came to be what we are: Homo sapiens  We are the only human species in the world.  Neanderthals, our closest “relatives” disappeared 30,000 years ago.
    3. 3. Our Capacity For Culture: Our Biological Roots      (1) Our thinking ability (2) Our language ability (3) Our ability to make and use tools (4) Our bipedalism—ability to stand and walk on two feet If the “science of humankind” is to be taken seriously, we need to know our own anatomy
    4. 4. Topics of This Section I        We start with the taxonomy, and where we fit in the animal kingdom. We then look at human anatomy and compare it with the chimps. Primary foci of the analysis of our anatomy: Capacity for thinking Capacity for language Capacity for tool making and use Capacity for bipedalism, which enables us to do many other things.
    5. 5. Topics of This Section II      We then look at hominin/hominid fossils and the tools they made—or didn’t make. We then look at the behavior of our closest relatives —the chimps, bonobos, and gorillas. For example, we diverged from our chimpanzee ancestors 6 million years ago (6 mya) By observing nonhuman primate behavior (monkeys and apes), we might get an inkling of fossil hominin behavior too—and of our own. All of these have a bearing on our capacity for culture.
    6. 6. First Things First: Taxonomy     Definition: Hierarchical, systematic classification of all lifeforms From the general (kingdom. Phylum, class, order) To the specific (genus, species, variety) Taxon (pl. taxa): categories at all levels from broad to specific
    7. 7. Taxonomy: Binomial Nomenclature          Every species has at least two names Genus: Homo Species: sapiens Variety: sapiens? (If we accept the lumpers’ terms) Stylistic Convention Italicize or underline all names Capitalize the genus Lowercase the species and variety Example: Homo (sapiens) sapiens
    8. 8. Taxonomy: The General Taxa      Kingdom: Animalia (ingests food, moves) Phylum: Chordata (has spinal cord) Subphylum: Vertebrata (has segmented protective bone or cartilage) Class: Mammalia (warm blooded, female secretes milk, has hair or fur) (Pop quiz: what is our constant temperature fixed at?)
    9. 9. Taxonomy: Order Primata       Order: Primata Larger brain relative to body size. Stereoscopic vision: eyes angled toward the same direction, enabling depth perception Flexible digits: Hands only in humans; hand and feet with other primates. Complex sociability: We live in groups but have complex interactions, from grooming to dominance hierarchies to infant rearing. Suborder: Anthropoidea (monkey, apes, humans)
    10. 10. Taxonomy: Suborder Anthropoidea      Suborder Prosimii: These are the lemurs, tarsiers, and other so-called prosimians. The don’t look much like human, but have all the features of primates. Suborder Anthropoidea (“Manlike”) These are the monkeys (New World, Old World) and apes They look like men: almost upright, hands like ours, even the feet look similar.
    11. 11. Taxonomy: Superfamily Hominoidea         Superfamily Cercopithecoidea: Old World Monkey Most have tails, smaller brained, smaller in size. Superfamily Hominoidea: All apes and humans. They look even more humanlike than the monkeys Larger brains No tails Larger body size Social behavior more humanlike
    12. 12. Taxonomy: Hominids (Old Taxonomy)      Now the confusion begins Old taxonomy: three hominoid families Hylobatidae or Hylobates: the lesser apes— gibbons and siamangs Pongidae, or pongids: Orangutans (SE Asia), gorillas, chimpanzees, and bonobos (all African apes) Hominidae: All bipedal humans and prehumans: Ardipithecus, Australopithecus and Homo
    13. 13. Taxonomy: Hominids (New Taxonomy)     This is the new taxonomy: Hominids apply to all humans and African apes Hominins apply to Homo sapiens and All extinct ancestors: Australopithecus, Homo habilis, H. erectus, H. heidelbergensis, and H. neanderthalensis
    14. 14. On Hominid Taxonomy, DNA, and Monkey Wrenches       Why can’t they leave well enough alone? Answer: DNA comparisons versus morphology Humans and chimps DNA genomes vary only by about 99.5%; gorillas, by about 99% or so. Human and Orangutan genomes vary by about 95%, justifying another taxon, pongidae (orangutans); the hylobates (gibbons) are even more distant. The new taxonomy is justified by genetic variations We’ll stick to the old system for now; but you should know that this issue exists.
    15. 15. Human Comparative Anatomy      Why anatomy? We need to know what biological features give us the capacity for culture. The brain is the seat of thinking ability, language, and even tool use. Our vocal tract enables speech, as we will see in the unit on language. Our hands are key to our ability to make and use tools. Our ability to stand and walk on two feet frees our hands to do these things and many others.
    16. 16. Overview: The Human Skeleton    You do need to know some of the parts of the human skeleton Use the online graphics (such as this) Or your printed handouts
    17. 17. Where It All Begins: The Brain         Frontal Lobe and Motor Cortex: Cognition Motor Abilities Parietal Lobe: Touch and Taste Primary somatosensory cortex: feedback from our motor abilities Temporal Lobe: Hearing Occipital Lobe: Vision Olfactory Bulb: Smell
    18. 18. Frontal Lobe: Cognitive Areas       The Frontal Lobe directs much of our thinking Note the following: Executive area for task management Working memory for spatial tasks Working memory for object recall tasks Area for solving multitask problems
    19. 19. Parts of the Brain: Motor Cortex, Cross Section         Related to Language: Lower Part: Lips Tongue Vocalization Related to Tool Making and Use: Upper part: Fingers and Thumb Hand Arm
    20. 20. Cerebral Cortex: Essential Language Centers      These are the essential language centers: Broca’s area (purple): where speech is generated Wernicke’s area (orange brown): where speech is received and processed Arcuate fasciculus (green bundle): transmission between speech generation and reception Geschwind’s territory: where the five senses are interconnected.
    21. 21. Parts of the Brain: Language Centers in Context I Parts of Cerebrum: Frontal Lobe (Thinking) Motor Cortex: Voluntary movement Somato-Sensory Cortex: Feedback from voluntary movement
    22. 22. Parts of the Brain: Language Centers in Context II Parts of Language Mechanism Broca’s Area (Speech production)) Temporal Lobe (Hearing) Auditory Cortex (Hearing) Wernicke’s Area (Speech reception) Arcuate Fasciculus (Coordinator of Broca’s with Wernicke’s areas
    23. 23. Parts of the Brain: Language Centers in Context III Parts that provide content to language: Parietal Lobe (Taste and touch) Occipital Lobe (Sight) Geschwind’s Territory (Intersensory Connector Angular Gyrus (Specialized part that links sound with meaning; coordinates touch, taste, sight, and hearing)
    24. 24. Comic Relief, Anyone? (Courtesy of Geico)  So easy a caveman can do it. . . .?
    25. 25. Human Skull        Note the following: High forehead Rounded skull No brow ridge Chin is present Teeth are small The bones are named after the lobes of the brain they cover
    26. 26. Skull Morphology: Chimp and Human      Note the following Larger brow ridge (supraorbital torus) of chimp than human’s Sloping forehead of chimp compared to human More prognathous jaw of chimp compared to human Larger canine and gap (diastema) of chimp than human
    27. 27. Human and Chimp Skulls Compared: Brain Structure       Compare the following Chimp’s brain is much smaller (400cc vs 1400cc) It has reduced frontal lobe It has no Broca’s or Wernicke’s area It does have Brodmann’s area 10, where calls may originate—but no speech It does have planum temporale, where calls are received—but not processed as language
    28. 28. What This All Means     Our brains are larger than the chimps’ We have a well-developed frontal lobe We have well developed language areas: Broca’s and Wernicke’s area The motor strip is more well developed among humans than among chimps
    29. 29. Dentition      For each jaw (upper or maxilla or lower or mandible: Incisors (4) for cutting Canines (cuspid) (2) for piercing Premolars (4) for light grinding Molars (6) for grinding
    30. 30. Chimp and Human Jaws     Note the following: Dental Arcade: Humans’ are arclike; apes, parallel back teeth, which are larger than human molars Canines and Diastema (gap): Apes have larger canines and gaps in opposite jaw to fit them; humans do not Ape incisors are more horizontal than vertical.
    31. 31. Anatomy of Tool Making and Use: The Hand        Note The Following: Our digits are straight Our thumb is opposable The thumb is long The wrist bones are known as carpals. The bones of the hand are called metacarpals. The fingers are known as phalanges.
    32. 32. Ape and Human Hands      Hands of orangutan, chimpanzee, gorilla and human Note the following: Our thumbs are longer than the others’ We can make a finer grip than the others can Less visible: apes’ digits are curved, ours are straight
    33. 33. Power and Precision Grip Note the Following:  Power grip: Fingers and thumbs wrap around the object  Precision grip: Forefingers and thumb hold the object  Importance: We can do finer work compared to nonhuman primates
    34. 34. Bipedalism     We are the only mammals that can stand and walk on two feet Kangaroos hop and maintain balance with their tails Apes are semibipedal, but use their knuckles to get around Notice the human is on his knees, not just his feet
    35. 35. Chimp and Human Locomotion
    36. 36. Advantages of Bipedalism        Efficient locomotion Freeing of hands Foraging and hunting/scavaging Tool making and use Care and provisioning of offspring Tracking migrating herds Predator avoidance
    37. 37. Vertebral Column and Pelvis      Note the following Human vertebral column is S-Shaped Chimp verebral column is bow-shaped Human pelvis, with ilium, is bowl-shaped Chimp pelvis is long, with flat ilium
    38. 38. Pelvis and Femur      Note the following: Longer ilium of chimp Shorter, more curved ilium of human Straight vertical orientation of chimp femur Inward angle of human femur
    39. 39. Foot Structure     Note the following: Large toe of chimp foot (right) is opposable to other digits Large toe of human foot (left) is aligned with other digits Ankle bones (tarsals) of human food are larger and more rigid than the chimps’
    40. 40. Foot Arch: Longitudinal and Transverse       Note the following: Longitudinal arch reflected from First metatarsal to Calcaneus (heel bone) Transverse arch can be inferred from Lower placement of outside foot.
    41. 41. The Evolution of Humankind      The fossil records tells us one thing: human populations today are very different from those one million years ago. Human biological evolution is well established for that reason. This section provides a cultural and intellectual history of creationism and evolutionism It describes the mechanisms of evolution It concludes with a record of both biological and cultural evolution to the present.
    42. 42. The Model of Evolution      The model of evolution: genetic change interacting with environmental pressures Mutation: Genetic change that is random Natural Selection: environmental pressures that favor some lifeforms over others Gene Flow: Change in the population by migration of life form from another population Genetic Drift: Change induced in small population by differential reproduction of the new lifeform.
    43. 43. Early Models: The Great Chain of Being    A hierarchy of entities from the simplest to most complex anticipated the later rise of taxonomy; Karl von Linné (discussed below) drew on this model. In this view, the human race was the most complex and perfect of all living forms Humans, however, were below the divine beings (including demons in the model depicted here.
    44. 44. Catastrophism     Earth’s history is product of sudden change Example: Creation of Earth in six days (upper left), including Adam Example: Flood (Noah’s Ark), which eliminated all life except Noah’s family and the male and female animals he allowed into the ark Catastrophism does have some basis of reality: an asteroid that struck the earth 65 million years ago (lower left) nearly destroyed all life
    45. 45. Catastrophists: Ussher and Linnaeus      James Ussher (1581-1656): Argued that humankind created noon, Oct. 23, 4004 BCE (Upper left) He based his calculations on biblical history and astronomy Carolus Linnaeus (Carl Linné; 17071778) Inventor of taxonomy—classification of lifeforms based on similarities and differences (Sample taxonomy next slide) Viewed system as divinely ordained
    46. 46. The Garden of Eden: Overview   Location: Southern Iraq where the Tigris and Euphrates meet (left) The Garden of Eden, Home of the First Couple—and of Original Sin
    47. 47. The Garden of Eden: The Myth     The beginning: Adam and Eve live in the Garden of Eden God: “Of every tree, thou mayest eat freely But of the Tree of Knowledge of Good and Evil, thou mayest not eat For in the day thou eatest of it, thou shalt surely die”
    48. 48. Garden of Eden: The Temptation      Tempted by the Serpent, Eve does so (left) She is the one who starts the Fall Tempted by Eve, Adam also eats the fruit God confronts the pair for having done so (lower left) Despite their supplications, He carries out His punishment
    49. 49. Garden of Eden: The Expulsion       The couple is expelled from the Garden of Eden Consequences: Woman must bear the pain of childbirth And be subject to man’s dominion Man toils by the sweat of his brow The serpent is forever reviled
    50. 50. Of Course, Others Besides Adam Talk to God . . .    But was bombing the Garden of Eden back to the Stone Age Something God had in mind? (Censored by the FCC)
    51. 51. Uniformitarianism    Definition: All geological processes occurred in the past as they do today Implications: It takes millions, perhaps billions of years for the geological processes to take place The earth could not be only 6,000 years ago as Ussher would have claimed
    52. 52. Uniformitarianism According to Charles Lyell        Charles Lyell (1797-1875) Espoused extreme form of uniformitarianism by denying catastrophism (Principles of Geology) Three aspects hold up today Geological processes of past are the same as today Stratigraphy serves to reconstruct history of the earth Immense amount of time necessary for geological processes to effect change in the landscape Age of earth: The current estimate is 4.5 billion years
    53. 53. Evolutionary Theories: Natural Selection      Natural selection defined: Evolutionary change by Differential reproductive success of individuals within a species (group of organism able to reproduce fertile offspring) Through successful adaptation to an environment
    54. 54. Charles Darwin (1809-1882) Origin of Species    Charles Darwin (above) observed that pigeons, dogs, and horses were subjected to artificial selection in order to improve their breeding On Galapagos Islands in 1832, Darwin observed that 13 species of finches adapted in different niches descended from a common ancestor (next slide) He conceived the idea of natural selection and after years of dithering finally published his conclusions in The Origin of Species in 1859
    55. 55. Charles Darwin and Natural Selection
    56. 56. Natural Selection: Definition and Implications        Variations are already present when selection occurs Natural selection has no particular direction— change is random Therefore, not all evolution is from the simple to the complex Species can and do become extinct New species can and do arise (Darwin had no way of explaining how the originated, however.) New species fill new niches Dark-winged moths filled a new environment in a soot-darkened coal-fired steel city; birds couldn’t see them
    57. 57. Genetics and Mutation      Natural selection is one principle of evolution. Species proliferate Some are removed by natural selection. But how do new species emerge in the first place? An Austrian Monk, Gregor Mendel, provided a partial answer
    58. 58. Principles of Evolution: Genetics I       Gregor Mendel: Genetic theory, based on experiments with peas Genes: Hereditary information determining physical characteristics Genotype: the genetic makeup of a particular characteristic (color of flowers in pea plant) Phenotype: the physical characteristics created by the genetic makeup Genes are always paired: male contributes half, female contributes half Alleles: Variations of a genetic characteristic
    59. 59. Principles of Evolution: Genetics II       When different alleles combine: Allele of one manifests in physical characteristic (Dominant) The other does not (Recessive) Or both may manifest as hybrid (Codominant) Traits change when mutation occurs in the genes change in the sex cells of one or both individuals. This process of mutation requires information beyond the scope of this course.
    60. 60. Reconstructing Fossil Hominins and their Tools     If taxonomies keep changing, it’s because we rely on fragments and infer from them Human remains: mostly teeth, bones, and stones—because they are preserved the best Here is Lucy—that’s one of the most complete remains we have that is dated 3.7 million years Here are two stone choppers—we think (lower left)
    61. 61. Trends in Human Evolution: Australopithecus to Homo       Australopithecus afarensis to A. africanus: Gracile Australopithecines Paranthropus robustus and P. boisei: Robust Australopithecines—Dead end? A. africanus to Homo habilis: Rise of tool manufacture? H. habilis to H. erectus: Migration throughout Old World; more kinds of tools H. erectus to H. heidelbergensis to H. sapiens: Tool specialization and population explosion to New World H. neanderthalensis: Dead end?
    62. 62. Fossil Hominins: Skull, Arms, Hands         Large bulbous cranium Short face compared to ape Vertical carriage of head Shortened forelimb Hands (manipulation, not locomotion) Enlarged thumb Straight fingers, not curved Enhanced finger sensitivity
    63. 63. Fossil Hominins: Bipedalism        S-shaped vertebrae (backbone) Short, wide, bowl-shaped pelvis Femoral head (ball of femur at pelvis) angled and strengthened Lengthened hindlimb Angle of knee: femur “slopes” to pelvis Platform (arched) structure of foot Nonopposable big toe; toes not curved
    64. 64. Encephalization (a.k.a. Bigger Brains)  Defining Cranial Capacity (and cc’s)  Ardipithecus ramidus: ca. 400 cc A. afarensis: 390-500 cc; av. 440 cc A. africanus: 435-530 cc; av. 450 cc A./P robustus: 520 cc, one specimen A.P. boisei: 500-530 cc; av. 515 cc. H. habilis: 500-800 cc; av. 680 cc. H. erectus: 750-1250 cc; av. 1000 cc H. neanderthalensis: 1300-1750 cc; av. 1450 H. (s.) sapiens: 900-2350 cc. av. 1400        
    65. 65. Lucy (Australopithecus afarensis) the Former First Biped—and Us            Note the Following: Shorter (3’6”) Longer arms Curved fingers Shorter lower legs Greater prognathism Sloped forehead Smaller cranial capacity What are the Similarities? Hint: it’s all related to bipedalism Give up? Check on Ardi, next slide.
    66. 66. Ardipithecus ramidus: The New Kid on the Fossil Hominin Block           What’s new? Ardi is bipedal She has an opposable toe She lived in a wooded environment She is dated at about 4.4 mya Otherwise,. . . About 4 feet tall Longer arms Cranial capacity: 400 cc Curved fingers and the rest.
    67. 67. Ardipithecus ramidus: A Comparison with Other Fossil Hominins
    68. 68. When We Became Bipedal (According to Gary Larson)   “Hey! Look! No hands!” (Does he look like Lucy to you. . .?)
    69. 69. Gracile and Robust Australopithecines          For A. africanus (top), note: Somewhat rounder skull No sagittal crest Prognathous jaw For Paranthropus boisei, note: Sagittal crest (ate a lot of veggies) Massive lower jaw (mandible) Flatter face Massive cheek bones (zygomatic arch)
    70. 70. Homo habilis: The First Known Toolmaker  Note the following:  Face is much flatter Reduced brow ridge (supraorbital torus) Larger cranial capacity (680 cc.)    Toolmaking Technique  Hammerstone used to strike A core (lump of stone) to knap A Flake (stone chip) Note: Stone has to be crystalline (so it will fracture predictably)   
    71. 71. Homo erectus: Cranial Structure         Note the Following: Cranial capacity: 1,000 cc Occipital bun Reduced brow ridge Reduced sloping forehead Reduced prognathism No chin; jaw is reinforced by a simian shelf Artist’s conception of H. erectus
    72. 72. Homo Erectus (H. ergaster to Some): Postcranial Skeleton  Note the following:  Fully bipedal Arms about length of Homo sapiens Cranial capacity: 1000 cc (average) Main apelike features: Prognathous lower face Sloping forehead     
    73. 73. Lower Paleolithic         Oldowan Tradition: Four or five strokes Unspecialized: choppers Flakes also made and used Acheulean Tradition: 50-75 strokes Symmetrical design Multiple uses: cutting, piercing, chopping
    74. 74. Homo heidelbergensis (a.k.a. “Archaic” Homo sapiens       Note the following: Brow ridges much reduced Forehead is higher, though sloping Reduced prognathism Cranial capacity 1200 cc. Artist’s conception shows closer similarities to ourselves
    75. 75. Manufacturing Levallois Cores and Flakes        Knappers: Selects the appropriate core, up to a pound of stone Strikes the edge of the core Knaps the surface of the intended flake Knocks off the flake Retouches the flake to desired shape May knap four to five flakes
    76. 76. Homo neanderthalensis and H. sapiens skull  Note the following for “Classic” Neanderthal  Greater prognathism; humans lower jaw is straight Absence of chin that humans have. Presence of brow ridge; human has none, has higher forehead Presence of occipital bun Larger cranial capacity: 1450 cc vs. 1400 cc in humans Also note: Artist’s conception of Neanderthal child     
    77. 77. Homo neanderthalensis and H. sapiens: Postcranial Skeletons  Note the following for Neanderthals:  Heavier brow ridge and sloping forehead Bones generally more robust Larger rib cage Broader pelvis Shorter forearm Shorter tibia Larger ankle joint      
    78. 78. Neanderthal Tools: Mousterian and Châtelperronian Traditions           Mousterian (top) Bordes: 63 types Burins (engravers) Scrapers and knives Even a type of handaxe Part of the Mesolithic Châtelperronian (bottom) First blades—by Neanderthals Definition: flakes twice as wide as they are long Initiated the Upper Paleolithic
    79. 79. Upper Paleolithic: Modern Human Tool Traditions.        Commonalities of Tools: Blades: Ever thinner and smaller Increased tool specialization Other material: bone, ivory, antler Other Developments Artwork (such as this mural at Altamira, Spain) Ornamentation (Venus statuettes)
    80. 80. Review and Conclusion      We have. . . Looked at the biological bases of culture: for language, toolmaking, and bipedalism Compared our anatomy with chimps, our closest relatives Discussed evolutionary change based on natural selection and mutation Looked at our ancestors and the tools they made
    81. 81. The Territory Ahead          Nonhuman Primate Behavior: How close in behavior are our cousins? Language: The medium of culture Making a Living: Industrial societies are not the only cultures in the world Sex, Family, and Its Extensions: The world’s first social organizations Economics: How goods and services are provided Social Control: Governance and law Psychology: Freud didn’t start it all The Supernatural: Were there gods before God? Culture Change and Globalization: Is there life outside corporations?