Biological Anthropology Notes PDF

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Madi Hawkins Biological Anthropology Chapter 1 Notes ●

Primate- member of the mammalian order Primates, including prosimians, monkeys, apes, and humans, defined by a suite of anatomical and behavioral traits ● Evolution- a change in the frequency of a gene or a trait in a population over multiple generations ● Biological Anthropology- the study of humans as biological organisms, considered in an evolutionary framework; sometimes called physical anthropology ● Hominin- a member of the primate family Hominidae, distinguished by bipedal posture and, in more recently evolved species, a large brain ● Adaptation- a trait that increases the reproductive success of an organism, produced by natural selection in the context of a particular environment Anthropology and Its Subfields ● Anthropology- the study of humankind in a cross-cultural context. Anthropology includes the subfields cultural, linguistic, archaeology, and biological anthropology ● Culture- the sum total of learned traditions, values, and beliefs that groups of people (and a few species of highly intelligent animals) possess. ● Biocultural Anthropology- the study of the interaction between biology and culture, which plays a role in most human traits The Scope of Biological Anthropology ● Cultural Anthropology- the study of human societies in a cross-cultural perspective ○ Ethnology- the study of human societies and of the behavior of people within those societies ● Linguistic Anthropology- the study of the form, function, and social context of language ● Archaeology- the study of how people used to live, based on the materials, or artifacts, they left behind ● Paleoanthropology- the study of the fossil record of ancestral humans and their primate kin ● Osteology- the study of the skeleton ● Paleopathology- the study of diseases in ancestral human populations ● Bioarchaeology- the study of human remains in an archaeological context ● Forensic Anthropology- the study of human remains applied to a legal context ● Primatology- the study of nonhuman primates and their anatomy, genetics, behavior, and ecology ● Human Biology- subfield of biological anthropology dealing with human growth and development, adaptation to environmental extremes, and human genetics The Roots of Modern Biological Anthropology ● Physical Anthropology- the study of humans as biological organisms, considered in an evolutionary framework ○ What does it mean to be human? ○ How did we become who we are today?

Madi Hawkins Biological Anthropology Class Notes 1/11 Biological Anthropologists as Social Activists ● Dr. Christophe Boesch- primatologist ● Dr. W. Montague Cobb- skeletal biologist/ physician ● Argentine Forensic Anthropology Team ● Dr. Paul Farmer- medical anthropologist/ physician What makes us different…? ● Bipedal, Hunting, Nonhoning Chewing (apes have canine teeth that automatically sharpen as they open and close their mouth), Bigger Brains, etc. Evolutionary Thought ● Science- a body of knowledge gained through observation and experimentation ○ It is empirical, repeatable, and falsifiable ● “Nothing in biology makes sense except in the light of evolution” ● What is evolution? ○ Defined as change over time ○ Central issue in anthropology is how our species developed over time and space ● Mechanisms of Evolution ○ There are four forces behind evolution ■ Mutation ■ Gene Drift ■ Gene Flow ■ Natural Selection ○ These are also known as micro-evolutionary forces ○ Mutation- A change in the DNA sequence ■ Can be deleterious, neutral, or advantageous ○ There are 3 types of mutations ■ Insertions ■ Deletions ■ Point mutations ● Genetic drift- random change in allele frequency from one generation to the next ○ Result of isolation and Founders Effect ● Gene flow- exchange of alleles between populations (also known as admixture) ○ Occurs with migration with the two exceptions, one with a population coming to a place, leaving their genes, and then leaving the place (pirates) and another when people choose their mate within their own group ● Natural Selection- differential reproductive success over multiple generations ○ 3 principles behind natural selection ■ Struggle for existence ■ Individual variability— differential survival (“survival of the fittest”) ■ Inheritance of this variation

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Important points about natural selection ■ Acts only on already existing genes ■ Can not usually be predicted ■ Can test for natural selection ● Mechanisms of Evolution: important points ○ Evolution is differential reproductive success over multiple generations ○ 4 micro evolutionary forces ○ Evolution acts on populations NOT individuals ○ Evolution is not linear-adaptive radiation ○ Evolution does not have a fixed endpoint History of Evolutionary Thought ● Immutability of species ● 18th and 19th centuries, European natural historians began to develop alternatives to the idea of the immutability of species ○ Catastrophism ○ Lamarckianism ● Georges-Louis Leclerc, comte de Buffon Naturalist, mathematician, biologist, cosmologist, and author- wrote that he knew things were changing over time but he wasn’t sure how ● Georges Cuvier, zoologist and paleontologist- developed Catastrophism— catastrophic events destroyed species that were later replaced by the creation of new organisms, accounted for the existence of fossils ● Jean-Baptiste Lamarck, botanist and zoologist, developed Lamarckianism— idea of inheritance of acquired characteristics ● James Hutton and Charles Lyell developed the idea of uniformitarianism— geological processes are uniform across time. Based on Hutton’s idea of gradualism geologic process occur over long periods of time The Theory of Evolution: The Context for Darwin ● Taxonomy and systematics- concerned with classifying organisms with the goal of defining how they are related in an evolutionary sense ● Nomenclature system used today was first developed by Charles Linnaeus ● Thomas Malthus- Essay on the Principle of Population ○ Wrote about the influences on Population size and competition for limited resources ○ “Struggle for existence” ● Darwin’s Contribution- the origin of species ○ “Much light will be thrown on the origin of man and his history” (line in book later thrown out due to creationist theories) ● Darwin’s Theory Evolves ○ Gregor Mendel’s research on pea plants became the foundation of modern genetics ○ Provided a mechanism of how traits were inherited ○ Mendel’s research refuted the idea of blending inheritance

○ Concluded that (what we now call) genes are responsible for what is inherited ○ Genes come in different forms (alleles) which can be dominant or recessive ● The combination of Darwin’s theory of evolution and Mendel’s theory of heredity is known as the modern synthesis ● According to modern synthesis, there are three other causes of evolution other than natural selection Molecular Basis of Evolution ● Discovery of DNA by R. Franklin (not credited) F. Crick, M. Wilkins, and J. Watson Icons of Evolution

Madi Hawkins Biological Anthropology Chapter 2 Notes What is Science? ● Deduction- a conclusion that follows logically from a set of observations ● Observation- the gathering of scientific information by watching a phenomenon ● Hypothesis- a preliminary explanation of a phenomenon. Hypothesis formation is the first step of the scientific method ● Experimentation- the testing of a hypothesis ● Data- the scientific evidence produced by an experiment or by observation, from which scientific conclusions are made ● Scientific Method- standard scientific research procedure in which a hypothesis is stated, data are collected to test it, and the hypothesis is either supported or refuted ● Falsifiable- able to be shown to be false ● Paradigm- a conceptual framework useful for understanding a body of evidence The Early Thinkers ● Theology was a pervasive force during the Middle Ages, not only spiritually but also legally and politically ● During the Renaissance, scholars rediscovered the knowledge of the ancient Greeks and Romans, and their approach to science became more “modern” ● Taxonomy- the science of biological classification ● Binomial Nomenclature- Linnean naming system for all organisms, consisting of a genus and species label ● Taxon- a group of organisms assigned to a particular category The Road to the Darwinian Revolution ● Comte De Buffon- accepted the notion of biological change ● Georges Cuvier- catastrophism- cataclysmic disasters were believed to have wiped out earlier forms of life on Earth ● Geoffroy Saint-Hilaire- strong advocate of evolutionary change ● Jean-Baptiste Lamarck- theory of inheritance of acquired characteristics- often called Lamarckism- argued that all organisms make adjustments to their environment during their lifetime that could be passed on to their offspring, making those offspring better adapted to the environment ● Uniformitarianism- theory that the same gradual geological process we observe today was operating in the past (Hutton and Lyell) The Darwinian Revolution ● Biogeography- the distribution of plants and animals on Earth ● Adaptive Radiation- the diversification of one founding species into multiple species and niches ● Natural Selection- Differential reproductive success over multiple generations ○ Survival of the fittest (fittest being reproductive success)

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Evolution- a change in a population (a breeding group of organisms of the same kind) in the frequency of genetic material, in which alterations in the DNA sequence provide the raw source of variation— mutation— on which natural selection can act ○ Mutation- an alteration in the DNA that may or may not alter the function of a cell. If it occurs in a gamete, it may be passed from one generation to the next Science and Creationism ● Creation science- a creationist attempt to refute the evidence of evolution ● Intelligent Design- a creationist school of thought that proposes that natural selection cannot account for the diversity and complexity of form and function seen in nature ●

Madi Hawkins Biological Anthropology Chapter 3 Notes ●

Cellular and molecular genetics- the study of genetics at the level of the basic building blocks of bodies (cells) and at the most fundamental level of genetic transmission (the DNA molecule) ● Classical or Mendelian genetics- involves looking at the pedigree of related individuals (plants or animals) and tracking how various traits are passed from one generation to the next ○ Pedigree- a diagram used in the study of human genetics that shows the transmission of a genetic trait over generations of a family ● Population Genetics- examines the genetic variation within and between populations at both the molecular level and the level of observable traits ● Phylogenetics- concerned with determining evolutionary relationships between species, usually by constructing treelike diagrams that visually indicate how closely or distantly species are related to one another ● Behavioral Genetics- involves trying to understand how the behavior of animals, including humans, is influenced by genetics The Cell ● Prokaryotes- single-celled organisms, such as bacteria, in which the genetic material is not separated from the rest of the cell by a nucleus ● Eukaryotes- a cell that possesses a well-organized nucleus ● Nucleus- in eukaryotic cells, the part of the cell in which the genetic material is separated from the rest of the cell (cytoplasm) by a plasma membrane ● Cytoplasm- in a eukaryotic cell, the region within the cell membrane that surrounds the nucleus; it contains organelles, which carry out the essential functions of the cell, such as energy production, metabolism, and protein synthesis ● Somatic Cells- the cells of the body that are not sex cells ● Gametes- the sex cells: sperm in males and eggs (or ova) in females ● Stem Cells- undifferentiated cells found in the developing embryo that can be induced to differentiate into a wide variety of cell types or tissues. Also found in adults, although adult stem cells are not as totipotent as embryonic stem cells ● Cell Anatomy ○ Deoxyribonucleic Acid (DNA)- a double stranded molecule that is the carrier of genetic information. Each strand is composed of a linear sequence of nucleotides; the two strands are held together by hydrogen bonds that form between complementary bases ○ Proteins- complex molecules formed from chains of amino acids (polypeptide) or from a complex of polypeptides. They function as structural molecules, transport molecules, antibodies, enzymes, and hormones ○ Protein Synthesis- the assembly of proteins from amino acids that occurs at ribosomes in the cytoplasm and is based on information carried by mRNA

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Ribonucleic Acid (RNA)- single-stranded nucleic acid that performs critical functions during protein synthesis and comes in three forms: messenger RNA, transfer RNA, and ribosomal RNA ○ Mitochondria- organelles in the cytoplasm of the cell where energy production for the cell takes place. Contains its own DNA ○ Endoplasmic Reticulum (ER)- an organelle in the cytoplasm consisting of a folded membrane ○ Ribosomes- structures composed primarily of RNA that are found on the endoplasmic reticulum. They are the site of protein synthesis DNA Structure and Function ● DNA Structure I: The Molecular Level ○ Nucleotide- molecular building block of nucleic acids DNA and RNA; consist of a phosphate, sugar, and base ○ Base- variable component of the nucleotides that form the nucleic acids DNA and RNA. In DNA, the bases are adenine, guanine, thymine, and cytosine. In RNA, uracil replaces thymine ● DNA Function I: Replication ○ Enzyme- a complex protein that is a catalyst for chemical processes in the body ● DNA Function II: Protein Synthesis ○ Hemoglobin- protein found in red blood cells that transports oxygen ○ Hormones- a natural substance (often a protein) produced by specialized cells in one location of the body that influences the activity or physiology of cells in a different location ○ Amino Acids- molecules that form the basic building blocks of protein ○ Polypeptide- a molecule made up of a chain of amino acids ○ Genetic Code- the system whereby the nucleotide triplets in DNA and RNA contain the information for synthesizing proteins from the twenty amino acids ○ Codon- a triplet of nucleotide bases in mRNA that specifies an amino acid or the initiation or termination of a polypeptide sequence ○ Gene- the fundamental unit of heredity. Consists of a sequence of DNA bases that carries the information for synthesizing a protein (or polypeptide) and occupies a specific chromosomal locus ○ Messenger RNA (mRNA)- strand of RNA synthesized in the nucleus as a complement to a specific gene (transcription). It carries the information for the sequence of amino acids to make a specific protein into the cytoplasm, where at a ribosome it is read and a protein molecule synthesized (translation). ○ Transfer RNA (tRNA)- RNA molecules that bind to specific amino acids and transport them to ribosomes to be used during protein synthesis ● DNA Structure II: Chromosomes and Cell Division ○ Chromatin- the diffuse form of DNA as it exists during the interphase of the cell cycle ○ Mitosis- somatic cell division in which a single cell divides to produce two identical daughter cells

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Meiosis- cell division that occurs in the testes and ovaries that leads to the formation of sperm and ova (gametes). ○ Chromosome- discrete structure composed of condensed DNA and supporting proteins ○ Centromere- condensed and constricted region of a chromosome. During mitosis and meiosis, location where sister chromatids attach to one another ○ Diploid Number- full complement of paired chromosomes in a somatic cell. In humans, the diploid number if 46 (23 pairs of different chromosomes) ○ Haploid Number- the number of chromosomes found in a gamete, representing one from each pair found in a diploid somatic cell. In humans, the haploid number is 23 ○ Homologous Chromosomes- members of the same pair of chromosomes (or autosomes). Homologous chromosomes undergo crossing over during meiosis ○ Locus- the location of a gene on a chromosome. The locus for a gene is identified by the number of the chromosome on which it is found and its position on the chromosome ○ Alleles- alternative versions of a gene. Alleles are distinguished from one another by their different effects on the phenotypic expression of the same gene ○ Homozygous- having the same allele at the loci for a gene on both members of a pair of homologous chromosomes ○ Heterozygous- having two different alleles at the loci for a gene on a pair of homologous chromosomes ○ Zygote- a fertilized egg ○ Crossing Over- exchange of genetic material between homologous chromosomes during the first prophase of meiosis; mechanism for genetic recombination ○ Recombination- the rearrangement of genes on homologous chromosomes that occurs during crossing over in meiosis. Source of variation arising out of sexual reproduction; important for increasing rates of natural selection ○ Karyotype- the complete chromosomal complement of an individual; usually based on a photograph of the chromosomes visualized under the microscope ○ Autosomes- any of the chromosomes other than the sex chromosomes ○ Sex Chromosomes- in mammals, chromosomes X and Y, with XX producing females, and XY producing males ○ Nondisjunction Errors- the failure of homologous chromosomes (chromatids) to separate properly during cell division. When it occurs during meiosis, it may lead to the formation of gametes that are missing a chromosome or have an extra copy of a chromosome Molecular Tools for Bio Anthropological Research ● Genome- the sum total of all the genes carried by an individual ● Polymerase Chain Reaction (PCR)- method for amplifying DNA sequences using the Taq polymerase enzyme. Can potentially produce millions or billions of copies of a DNA segment starting from a very small number of target DNA

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Mitochondrial DNA (mtDNA)- small loop of DNA found in the mitochondria. It is clonally and maternally inherited

Madi Hawkins Biological Anthropology Class Notes 1/18 Introduction to Human Genetics ● The Cell- generally referred to as “the building block of life” ○ Prokaryotes- generally unicellular, do not have a well formed nucleus and their organelles are not enclosed in any type of membrane ■ Bacteria- no nucleus ■ Archaea- tend to find them in extreme conditions ○ Eukaryotes- have a true nucleus, generally multicellular, carry genetic material in the nucleus and some of the mitochondria ○ Somatic and Germ cells ■ Somatic cells- most are diploid but N ranges from 0N-64N ■ 0N= red blood cells; 64N= megakaryocytes of bone marrow ■ One-cell fertilized egg is totipotent (has the potential to turn into different types of cells) ○ 210 types of cells in humans with some being organ specific and some able to differentiate a little bit ● Chromosomes ○ DNA is packed into chromosomes ○ Chromosomes are packed into the nucleus ○ Diploid number (2N=23 pairs) in most somatic cells ■ Types of chromosomes: autosomes and sex chromosomes ○ Half from the mother the other half from the father ■ Homologous chromosomes ○ Sex chromosomes: X and Y ■ Females: XX ■ Males: XY ○ Two copies of every gene ○ Maternal and paternal genes may differ ● Numbers of Chromosomes ○ Humans have 46 ○ Dogs and chickens have 78 ○ Fruit flies have 8 ○ Onions have 16 ○ Tobacco has 40 ● Chromosomal Structure ○ Telomeres ○ Centromeres ○ Origins of replication ○ Genes ● The Genetic Code- Nuclear DNA

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○ Only 1.5% codes for protein or RNA product ○ Tandemly repeated noncoding DNA is a huge portion of the genome The Genetic Code- Mitochondrial DNA ○ Extra-nuclear DNA ○ Contains 37 genes ○ High mutation rate ○ Exclusively maternally inherited DNA Structure ○ Large polymer defined by linear sequence with repeating units ○ Linear backbone of alternating sugar bases ○ Adenine and Guanine are purines which means they have two rings ○ Cytosine and Thymine are pyrimidines which means they only have one ring DNA Functions ○ Replicate itself ○ Make proteins (transcription/translation) Cell Division: Mitosis ○ DNA replicates then cell divides ○ ...