ANTH 2301 Intro to Physical Anthropology Study Guide Questions and answers

ANTH 2301 Intro to Physical Anthropology Study Guide Questions and answers Instructions for the Exam: This is a closed textbook exam. You will be allowed to use your completed study guide during the exam. You are not allowed to use any other study materials to assist you with the exam that includes the internet and friends. The exam consists of 90 multiple choice questions. The exam will open at 8 am on the day of the exam and you will have until 10 pm that day to take the exam. Once you begin the exam you will have 120 minutes (2 hours) to complete it. You must complete the exam in one sitting; you cannot pause the exam and come back later to finish. You are required to use Honorlock. This means that your computer must be equipped with a webcam and a microphone, and you will need a photo ID. What is Honorlock? Honorlock is used to proctor online exams. You will be prompted to download an extension to your computer. Once this is complete you can begin the test. 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Close this window. • Return to your eCampus page with the exam and click on the LAUNCH button. • You will now follow the prompts to show your ID and scan the room. • If you have ANY problems, click on the NEED HELP button. Be able to answer the following questions: Chapter 1 What is anthropology? - Anthropology is the scientific study of humanity, concerned with human behavior, human biology, cultures, societies and linguistics, in both the present and past, including past human species What is physical (biological) anthropology? What is the scope of biological anthropology? - Biological anthropology, also known as physical anthropology, is a scientific discipline concerned with the biological and behavioral aspects of human beings, their extinct hominin ancestors, and related non-human primates, particularly from an evolutionary perspective. - Physical or biological anthropology deals with the evolution of humans, their variability, and adaptations to environmental stresses. Using an evolutionary perspective, we examine not only the physical form of humans - the bones, muscles, and organs - but also how it functions to allow survival and reproduction. What is science? How does science differ from other ways of understanding the world? - Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe. The earliest roots of science can be traced to Ancient Egypt and Mesopotamia in around 3000 to 1200 BCE. - What Makes Science Different From Other Ways of Knowing? Unlike art, philosophy, religion and other ways of knowing, science is based on empirical research. Empirical research relies on systematic observation and experimentation, not on opinions and feelings. What is a hypothesis? What is a theory? How do they differ? - A hypothesis is a proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, the scientific method requires that one can test it. Scientists generally base scientific hypotheses on previous observations that cannot satisfactorily be explained with the available scientific theories. - A theory is a rational type of abstract thinking about a phenomenon, or the results of such thinking. The process of contemplative and rational thinking is often associated with such processes as observational study or research. - n scientific reasoning, a hypothesis is an assumption made before any research has been completed for the sake of testing. A theory on the other hand is a principle set to explain phenomena already supported by data. What is a hominin? What obligate behaviors do hominins exhibit? - The Hominini form a taxonomic tribe of the subfamily Homininae. Hominini includes the extant genera Homo and Pan and in standard usage excludes the genus Gorilla. The term was originally introduced by Camille Arambourg. Arambourg combined the categories of Hominina and Simiina due to Gray into his new subtribe. - Hominids are defined by two obligate behaviors: bipedal locomotion and nonhoning chewing. What are the key attributes that make humans unique? - The six key attributes that make humans unique relative to other primate species are bipedalism, non-honing chewing, complex material culture and tool use, hunting and control of fire, speech and language, and dependence on domesticated foods. What is the scientific method? How does it operate/what are its principles? - The scientific method is an empirical method of acquiring knowledge that has characterized the development of science since at least the 17th century. It involves careful observation, applying rigorous skepticism about what is observed, given that cognitive assumptions can distort how one interprets the observation. - The basic steps of the scientific method are: 1) make an observation that describes a problem, 2) create a hypothesis, 3) test the hypothesis, and 4) draw conclusions and refine the hypothesis. Chapter 2 What is mitosis? What is meiosis? How do they compare? How do they differ? - n cell biology, mitosis is a part of the cell cycle in which replicated chromosomes are separated into two new nuclei. Cell division gives rise to genetically identical cells in which the total number of chromosomes is maintained. Therefore, mitosis is also known as equational division. - Meiosis is a special type of cell division of germ cells in sexually-reproducing organisms used to produce the gametes, such as sperm or egg cells. It involves two rounds of division that ultimately result in four cells with only one copy of each chromosome What is natural selection? Who discovered natural selection? - Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations. - Alfred Russel Wallace (1823–1913) is famously given credit for discovering, independently of Darwin, natural selection as the process accounting for the evolution of species - English naturalist Charles Darwin developed the idea of natural selection after a five-year voyage to study plants, animals, and fossils in South America and on islands in the Pacific. In 1859, he brought the idea of natural selection to the attention of the world in his best-selling book, On the Origin of Species. Who is Gregor Mendel? Why is he significant? - Gregor Mendel was an Austrian monk who discovered the basic principles of heredity through experiments in his garden. Mendel's observations became the foundation of modern genetics and the study of heredity, and he is widely considered a pioneer in the field of genetics. Why is Darwin’s On the Origin of Species considered so important? - On the Origin of Species' provided many answers to doubts that had arisen about the true age of the earth and the extensive fossil collection that had been discovered, yet it still left gaps in man's understanding of evolution, and left many religious and scientific thinkers uncertain of the truth What is Darwinian evolution? What does it propose? - Charles Darwin was a British naturalist who proposed the theory of biological evolution by natural selection. Darwin defined evolution as "descent with modification," the idea that species change over time, give rise to new species, and share a common ancestor. What are the forces of evolution? - The forces of evolution include founder effects, genetic drift, mutation, migration and selection. What did Mendel learn from his experiments with pea plants? - Gregor Mendel, through his work on pea plants, discovered the fundamental laws of inheritance. He deduced that genes come in pairs and are inherited as distinct units, one from each parent. Mendel tracked the segregation of parental genes and their appearance in the offspring as dominant or recessive traits. What is genetic drift? How does it affect small populations? - Genetic drift is the change in the frequency of an existing gene variant in a population due to random sampling of organisms. The alleles in the offspring are a sample of those in the parents, and chance has a role in determining whether a given individual survives and reproduces. - Small populations tend to lose genetic diversity more quickly than large populations due to stochastic sampling error (i.e., genetic drift). This is because some versions of a gene can be lost due to random chance, and this is more likely to occur when populations are small. What is DNA? What is its purpose/function? What does most human nuclear DNA code for? What are alleles? - DNA contains the instructions needed for an organism to develop, survive and reproduce. To carry out these functions, DNA sequences must be converted into messages that can be used to produce proteins, which are the complex molecules that do most of the work in our bodies. - Nuclear DNA encodes the primary structure of proteins, consisting of the basic amino acid sequence. - An allele is one of two, or more, forms of a given gene variant. For example, the ABO blood grouping is controlled by the ABO gene, which has six common alleles. Nearly every living human's phenotype for the ABO gene is some combination of just these six alleles. What is Mendel’s law of segregation? - According to the law of segregation, only one of the two gene copies present in an organism is distributed to each gamete (egg or sperm cell) that it makes, and the allocation of the gene copies is random. What is meiosis? What is the end result of meiosis? What happens to chromosome number during meiosis? - By the end of meiosis, the resulting reproductive cells, or gametes, each have 23 genetically unique chromosomes. The overall process of meiosis produces four daughter cells from one single parent cell. Each daughter cell is haploid, because it has half the number of chromosomes as the original parent cell. - the process by which the chromosome number is halved during gamete formation is meiosis. In meiosis, a cell containing the diploid number of chromosomes is converted into four cells, each having the haploid number of chromosomes The chromosomes of the two cells then separate and pass into four daughter cells. What is a recessive allele? How does a recessive allele affect the phenotype? - Recessive alleles only express their phenotype if an organism carries two identical copies of the recessive allele, meaning it is homozygous for the recessive allele. This means that the genotype of an organism with a dominant phenotype may be either homozygous or heterozygous for the dominant allele. Chapter 4 What are the forces of evolution? Describe each. - The forces of evolution include founder effects, genetic drift, mutation, migration and selection. - founder effects- The founder effect is the reduction in genetic variation that results when a small subset of a large population is used to establish a new colony. The new population may be very different from the original population, both in terms of its genotypes and phenotypes. - genetic drift- Genetic drift describes random fluctuations in the numbers of gene variants in a population. Genetic drift takes place when the occurrence of variant forms - mutation- In biology, a mutation is an alteration in the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA - Migration is the movement of genetic diversity, usually within a species Selection is perhaps the best known of the processes affecting genetic diversity and is the only process that directly results in populations becoming better adapted to their environment. What is a mutation? - In biology, a mutation is an alteration in the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA What is the only source of new genetic material? - t should be noted that mutation is the ultimate source of genetic variation in all populations—new alleles, and, therefore, new genetic variations arise through mutation. What is microevolution? What is macroevolution? - evolutionary change within a species or small group of organisms, especially over a short period. - major evolutionary change. The term applies mainly to the evolution of whole taxonomic groups over long periods of time. What is Hardy Weinberg equilibrium? What does it assume? - In population genetics, the Hardy–Weinberg principle, also known as the Hardy– Weinberg equilibrium, model, theorem, or law, states that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences. What is directional selection? What is stabilizing selection? - n population genetics, directional selection, is a mode of negative natural selection in which an extreme phenotype is favored over other phenotypes, causing the allele frequency to shift over time in the direction of that phenotype. - - Stabilizing selection is a type of natural selection in which the population mean stabilizes on a particular non-extreme trait value. This is thought to be the most common mechanism of action for natural selection because most traits do not appear to change drastically over time. What happens to variation between populations when gene flow occurs? What happens to variation between populations when mutations occur? - The effect of gene flow is to reduce genetic differences between populations, thereby preventing or delaying the evolution of the populations in different geographical areas into separate species of the pathogen. - The flow of individuals in and out of a population introduces new alleles and increases genetic variation within that population. Mutations are changes to an organism's DNA that create diversity within a population by introducing new alleles. Chapter 5 Why is race not a valid biological concept in humans? - Race' cannot be biologically defined due to genetic variation among human individuals and populations Why does human skin color vary? Why are dark-skinned people found in equatorial regions and light-skinned people at higher latitudes (away from the equator)? - People have different skin colors mainly because their melanocytes produce different amount and kinds of melanin. The genetic mechanism behind human skin color is mainly regulated by the enzyme tyrosinase, which creates the color of the skin, eyes, and hair shades. - As people moved to areas farther from the equator with lower UV levels, natural selection favored lighter skin which allowed UV rays to penetrate and produce essential vitamin D. The darker skin of peoples who lived closer to the equator was important in preventing folate deficiency. What is Bergmann’s rule? What does it predict? - Bergmann's rule proposes that animals in cold habitats will be larger than those in warm habitats. This prediction has been tested thoroughly at the intraspecific level, but few studies have investigated the hypothesis with interspecific data using phylogenetic comparative approaches. What is a cline? - In biology, a cline is a measurable gradient in a single character of a species across its geographical range. First coined by Julian Huxley in 1938, the “character” of the cline referred to is usually genetic, or phenotypic. What did Lewontin discover through his research? How did he demonstrate his findings? - Richard Lewontin used a method that separated proteins based on their molecular characteristics, obtaining very surprising results. The genetic variation between individuals in a population was many times greater than expected. The pattern was repeated in every species examined. What is Allen’s rule? How does it affect limb measurements? - A similar rule is Allen's (1877) rule, which states that, within endothermic [generating their own body heat] species, extremity length decreases as latitude increases, for similar thermoregulatory reasons In ectotherms, however, heat is not generated but absorbed from the external environment What are developmental adaptations? What are some examples of developmental adaptations discussed in the textbook? - Developmental adaptation refers to the ability of an organism to modify its phenotype in response to environmental exposures over the course of growth and development. Chapter 6 What is a primate? What are the general primate tendencies discussed in the textbook? - A primate is any member of the biological order Primates, the group that contains all the species commonly related to the lemurs, monkeys, and apes, with the latter category including humans All primates have five fingers (pentadactyly), a generalized dental pattern, and a primitive (unspecialized) body plan What are New World monkeys? What are their unique characteristics? - the noses of New World monkeys are flatter than the narrow noses of the Old World monkeys, and have side-facing nostrils. New World monkeys are the only monkeys with prehensile tails—in comparison with the shorter, non-grasping tails of the anthropoids of the Old World. - New World monkeys are the five families of primates that are found in the tropical regions of Mexico, Central and South America: Callitrichidae, Cebidae, Aotidae, Pitheciidae, and Atelidae. The five families are ranked together as the Ceboidea, the only extant superfamily in the parvorder Platyrrhini. What are lemurs? Where are they found? What are their unique characteristics? - Lemurs are primates belonging to the suborder Strepsirrhini. Like other strepsirrhine primates, such as lorises, pottos, and galagos, they share ancestral (or plesiomorphic) traits with early primates. - They are native only to the island of Madagascar. Most existing lemurs are small, have a pointed snout, large eyes, and a long tail. They chiefly live in trees (arboreal), and are active at night (nocturnal) What primates are great apes? - The Hominidae, whose members are known as great apes or hominids, are a taxonomic family of primates that includes eight extant species in four genera: Pongo; Gorilla; Pan; and Homo, of which only modern humans remain. What are the characteristics shared by all/most primates? - Explanation: Characteristics of all primates include four limbs, collarbones, a high degree of mobility in their shoulders, forward facing eyes, relatively dexterous hands, and a high degree of intelligence. Primates are an incredibly diverse genera, ranging from humans to lemurs What are the arboreal adaptations that modern primates possess? - This arboreal heritage of primates has resulted in adaptations that include, but are not limited to: 1) a rotating shoulder joint; 2) a big toe that is widely separated from the other toes and thumbs, that are widely separated from fingers (except humans), which allow for gripping branches; and 3) stereoscopic vision, What is dietary plasticity? - dietary plasticity. a diet's flexibility in adapting to a given environment. parental investment. the time and energy parents expend for their offspring's benefit. primate adaptation in microcosm What is brachiation? - Brachiation, or arm swinging, is a form of arboreal locomotion in which primates swing from tree limb to tree limb using only their arms. During brachiation, the body is alternately supported under each forelimb. Chapter 7 How does female social rank relate to access to resources and offspring survival rates? - In some species, for example, female sociality has a positive effect on infant survival. ... Offspring of highly social females, who were often high-ranking females, exhibited higher survivorship during stable periods compared with offspring of less social females. How do primates form alliances? - Among males, coalitions are often directly or indirectly related to mating effort. Female alliances usually occur in contests over resources that the victors can share Apes form coalitions at the individual and local group level only. To date, there are no reported inter- group alliances among wild apes. What demands does reproduction place on male primates? Female primates? Are they the same? - The success of male reproductive strategies can be measured by determining the number of sired infants that survive to independence. Because most primate females mate with more than one male during a reproductive cycle, genetic tests are required to determine paternity. - Because the reproductive physiology of male and female primates differs (males produce sperm and cannot gestate or lactate; females produce eggs and gestate and lactate), males and females differ with regard to parental investment and sexual selection strategies. Female strategies, on the one hand, focus on obtaining .. What is sexual dimorphism? - Sexual dimorphism is the condition where the sexes of the same species exhibit different characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most animals and some plants. What to female reproductive strategies emphasize? - Female reproductive strategies emphasize care of young and access to food for young and for the support of mothers' and their offspring's nutritional needs. How do primates acquire food? What type(s) of residence pattern is(are) associated with a lack of sexual dimorphism? What type(s) of residence pattern is(are) associated with high levels of sexual dimorphism? - Chapter 8 What are absolute dating techniques? How do they work? - Absolute dating methods determine how much time has passed since rocks formed by measuring the radioactive decay of isotopes or the effects of radiation on the crystal structure of minerals. Paleomagnetism measures the ancient orientation of the Earth's magnetic field to help determine the age of rocks What environments are the best for fossilization? - The most favorable environments for this process are hypersaline waters rich in carbonate minerals or ions, although oceanic (normal salinity) waters are conducive to fossilization as well. The terrestrial environment is the least likely to preserve fossils, which is why our knowledge of vertebrates is so incomplete. What is the principle of superposition? - The superposition principle, also known as superposition property, states that, for all linear systems, the net response caused by two or more stimuli is the sum of the responses that would have been caused by each stimulus individually. What is the main difference between absolute and relative dating? - absolute dating is based on calculations of the age of rock strata based on half lives of minerals, relative dating is based on the assumed age of fossils found in the strata and the laws of super imposition. Carbon 14 (radiocarbon) dating can be used on what types of materials? Potassium-argon dating can be used on what types of materials? - C-14 dating is only applicable to organic and some inorganic materials (not applicable to metals). Gas proportional counting, liquid scintillation counting and accelerator mass spectrometry are the three principal radiocarbon dating methods. - The potassium-argon dating method has been used to measure a wide variety of ages. The potassium-argon age of some meteorites is as old as 4,500,000,000 years, and volcanic rocks as young as 20,000 years old have been measured by this method. Chapter 9 What primate traits are believed to have been selected for life in the trees? - stereoscopic vision and an opposable thumb What is the arboreal hypothesis? - The arboreal hypothesis proposes that defining primate characteristics were adaptations to life in the trees, such as: grasping hands and feet, developed vision, and greater intelligence. The visual predation hypothesis proposes that: primate traits arose as adaptations to preying on insects and small animals. What is the most likely explanation for how New World monkeys got to South America? - More Than 30 Million Years Ago, Monkeys Rafted Across the Atlantic to South America. In a strange twist of evolutionary history, the ancestors of modern South American monkeys such as the capuchin and woolly monkeys first came to the New World by floating across the Atlantic Ocean on mats of vegetation and earth Describe Sivapithecus. What group(s) is it considered to be ancestral to? - Sivapithecus, fossil primate genus dating from the Miocene Epoch (23.7 to 5.3 million years ago) and thought to be the direct ancestor of the orangutan. Though Sivapithecus was slightly larger than Ramapithecus, it was only a small-to-medium-sized ape about the size of a modern chimpanzee. - Sivapithecus, fossil primate genus dating from the Miocene Epoch (23.7 to 5.3 million years ago) and thought to be the direct ancestor of the orangutan. Describe Khoratpithecus. What group(s) is it considered to be ancestral to? - Khoratpithecus is an extinct genus of pongin primates that lived during the late Miocene (7–9 million years ago) in Myanmar and Thailand. Three species belong to this genus: ... Khoratpithecus piriyai from Thailand Chaimanee, Suteethorn, Jintasakul, Vidthayanon, Marandat & Jaeger, 2004. - It is therefore interpreted as its probable ancestor Thus Khoratpithecus represents a new lineage of Southeast Asian hominoids, closely related to extant great ape ancestors. What is the visual predation hypothesis? - Abstract. The visual-predation hypothesis proposes that certain derived features shared by crown primates reflect an insectivorous ancestry. Critics of this idea have argued that because insectivory is uncommon among extant primates it is unlikely to have been a major influence on early primate evolution. What groups of primates are found in the Eocene? What are their features? - The known fossil families of the Eocene Epoch (56 million to 33.9 million years ago) include the Tarsiidae (tarsiers), the Adapidae (which include probable ancestors of lemurs and lorises), and the Omomyidae (which include possible ancestors of the monkeys and apes). - in these early primates, with larger brains and eyes, and smaller muzzles being the trend. Where did the evolution of apes begin? Ape fossils dating to the Miocene have been found in what geographic areas? - Apes evolved from the catarrhines in Africa midway through the Cenozoic, approximately 25 million years ago. - Fossil remains of the genus are common in deposits of Asia, Europe, and Africa from the Miocene Epoch (23 to 5.3 million years ago). The genus persisted into the following Pliocene Epoch, and remains of a related genus, Moropus, are found in North America. Chapter 10 What are the anatomical/skeletal traits that indicate bipedality? (For example: an S-shaped spine) - Major morphological features diagnostic (i.e., informative) of bipedalism include: the presence of a bicondylar angle, or valgus knee; a more inferiorly placed foramen magnum; the presence of a reduced or nonopposable big toe; a higher arch on the foot; a more posterior orientation of the anterior portion of the iliac ... What features allow for the recognition of fossil hominins? What characteristics will tell you whether or not a fossil is a hominin? - Some characteristics that have distinguished hominins from other primates, living and extinct, are their erect posture, bipedal locomotion, larger brains, and behavioral characteristics such as specialized tool use and, in some cases, communication through language. What are the robust australopithecines? What do they look like? What unique adaptations do they have that suggest they had a diet that was tough to chew? - The "robust" australopiths are a group of fossil hominins that existed in East and southern Africa between approximately 2.5 and 1.4 million years ago (Ma). They are referred to here as members of the genus Paranthropus, though considerable disagreement about their proper taxonomy persists (see below). - A large sagittal crest provided a large area to anchor these chewing muscles to the skull. These adaptations provided P. robustus with the ability of grinding down tough, fibrous foods. What feature(s) do ALL australopithecines share? - The Australopithecus species, referred to as Australopithecines, had features that were both human-like and ape-like. Their brains were smaller and more in the range of the brains of modern apes. They tended to have longer arms that seemed well-suited to climbing.Sep 22, 2021 What are the advantages of bipedalism? - The host of advantages bipedalism brought meant that all future hominid species would carry this trait. Bipedalism allowed hominids to free their arms completely, enabling them to make and use tools efficiently, stretch for fruit in trees and use their hands for social display and communication. What can be learned from the Laetoli footprints? - The discovery of these footprints settled the issue, proving that the Laetoli hominins were fully bipedal long before the evolution of the modern human brain, and were bipedal close to a million years before the earliest known stone tools were made. Describe Australopithecus garhi. What group is it likely ancestral to? Why? - Australopithecus garhi is a species of australopithecine from the Bouri Formation in the Afar Region of Ethiopia 2.6–2.5 million years ago (mya) during the Early Pleistocene. ... A. garhi was originally considered to have been a direct ancestor to Homo and the human line, but is now thought to have been an offshoot. - garhi was originally considered to have been a direct ancestor to Homo and the human line, but is now thought to have been an offshoot. Like other australopithecines, A. Chapter 11 Which was the first hominin to leave Africa? - Homo erectus - The extinct ancient human Homo erectus is a species of firsts. It was the first of our relatives to have human-like body proportions, with shorter arms and longer legs relative to its torso. It was also the first known hominin to migrate out of Africa, and possibly the first to cook food. What are the general trends seen in human evolution? (For example, increase in brain size.) - Three other trends are important in the evolution of hominins: bipedalism, non-honing chewing complex, and encephalization of the brain. These are discussed in more detail next. What traits indicate that Homo erectus walked just like modern humans? - Homo erectus walked just like a modern human, with traits like: double arches and adducted big toe. The earliest fossil evidence for Homo erectus in Western Europe dates from: 1.2 mya from Sima del Elefante. What explains the increase in body and brain size seen in Homo erectus? - Brain size increased rapidly during human evolution due to the expansion of many brain regions, resulting in human brains being exceptionally larger than those of our closest relatives Larger animals also tend to have larger brains so it is important to consider body size, too. Describe the species debate regarding Homo habilis and Homo rudolfensis. - Homo rudolfensis had large and wider molars compared to Homo habilis. While their teeth were only slightly smaller than those seen in robust australopithecines, H. rudolfensis didn't have the heavily-built jaw and strong jaw muscle attachments seen in robust early humans How does Homo habilis differ from australopithecines? - The differences between Homo habilis and Australopithecus are: homo habilis possesses a greater cranial capacity(610 to about 800cc), it has reduced prognathism- a flatter face and a shorter tooth row Brain specialists see in casts made from habilis skulls the bulge of Broca's area How does Homo erectus differ from earlier hominins including Homo habilis? - How did Homo habilis differ from earlier australopithecines? Homo habilis had a larger brain. However, while Homo erectus had an increased brain size over Homo habilis, their average cranial capacity was still smaller than that of modern humans. Chapter 12 What are the characteristics of archaic Homo sapiens? Where is this species found? What does it look like? - Archaic humans had a brain size averaging 1,200 to 1,400 cubic centimeters, which overlaps with the range of modern humans. Archaics are distinguished from anatomically modern humans by having a thick skull, prominent supraorbital ridges (brow ridges) and the lack of a prominent chin. - Fossils of the earliest members of our species, archaic Homo sapiens, have all been found in Africa. Fossils of modern Homo sapiens have been found in Africa and in many other sites across much of the world. Sites older than 150k include Florisbad, Omo-Kibish, Ngaloba and Herto. Where have Neandertal fossils been found? - All traces of Neanderthals disappeared by about 40,000 years ago. The most recently dated Neanderthal fossils come from small areas of western Europe and the Near east, which was likely where the last population of this early human species existed. What do Neandertal bodies look like? What environment are they adapted for? - What did Neanderthals look like? Neanderthals had a long, low skull (compared to the more globular skull of modern humans) with a characteristic prominent brow ridge above their eyes. Their face was also distinctive. The central part of the face protruded forward and was dominated by a very big, - neanderthal populations were adaptable, living in cold steppe environments in England and Siberia about 60,000 years ago, and in warm temperate woodlands in Spain and Italy about 120,000 years ago. What happened to the Neandertals? - The last appearance date of Neanderthals is commonly cited as ca. 30 thousand years ago (ka). The Neanderthal disappearance is viewed by some as a true extinction. Others however, contend that Neanderthals did not become extinct, but instead were assimilated into the modern human gene pool. How did Homo sapiens get to the New World (the Americas)? - The settlement of the Americas is widely accepted to have begun when Paleolithic hunter-gatherers entered North America from the North Asian Mammoth steppe via the Beringia land bridge, which had formed between northeastern Siberia and western Alaska due to the lowering of sea level during the Last Glacial Maximu What are the two models for modern human origins? What are their main tenets? How do they differ from the more recent assimilation model? - omo erectus is an extinct species of human that lived between 1.9 million and 135,000 years ago. Historically, two key models have been put forward to explain the evolution? of Homo sapiens. These are the 'out of Africa' model and the 'multi-regional' model How do scientists define modern in terms of the study of human evolution? - In the study of human evolution, scientists define modern in terms of: a series of distinctive anatomical traits that contrast with archaic traits from earlier hominins. Chapter 13 What is the importance of domestication to the evolution of modern humans? - Domesticating plants and animals gave humans a revolutionary new control over their food sources. Domestication enabled humans to switch from foraging, hunting, and gathering to agriculture and triggered a shift from a nomadic or migratory lifestyle to settled living patterns. What were the impacts of domestication on human health? Population size? Birthrate? - A downside to domestication was the spread of diseases between humans and animals that would have otherwise jumped between species. Pig flu and transfer of parasites are just a few examples of humans and animals getting a little too close. But without domestication humans may well still be wandering hunter-gatherers. How did the adoption of agriculture affect settlement patterns? - When people adopt agriculture, they are forced to settle down. Agriculture allowed them to have a more steady source of food by making things grow they may not grow there naturally. Social groups grow in size and become less close knit, they also develop an elite class. What anatomical changes were brought about by the transition to agriculture? - The shift to agriculture and the eating of softer foods resulted in biological changes to the face, jaws, and teeth of modern people. Although not universal, some tendencies characterized the skulls and teeth of hunter-gatherers and of agriculturalists. What skeletal differences do we see between hunter-gatherer’s and agriculturalists’? - The new study, published today in the journal PNAS, shows that, while human hunter- gatherers from around 7,000 years ago had bones comparable in strength to modern orangutans, farmers from the same area over 6,000 years later had significantly lighter and weaker bones that would have been more susceptible to breaking What is the masticatory-functional hypothesis? - The masticatory-functional hypothesis states that: change in skull form represents a response to decreased demands on the chewing muscles.