Human Evolution & Genetics: Cultural Approaches to Selection & Heredity - Prof. G. Listi, Study notes of Introduction to Cultural Anthropology

Download Human Evolution & Genetics: Cultural Approaches to Selection & Heredity - Prof. G. Listi and more Study notes Introduction to Cultural Anthropology in PDF only on Docsity! Unit 1 Anthropology- study of man. Perspectives of Anthropology: -Biocultural Approach-helps to understand people; relationship between what humans have inherited genetically and what they learn culturally.  Humans are product of both genes and cultural approach.  -Holistic: Concerned with a whole system(includes everything about humans: behavior, how eat, reproduction, body structure)  -Comparative(Cross-culture): make comparisons to draw meaning  if different, why different  -Ethnocentric: view centered on a specific ethnic group(Usually one’s own ethnic group).  Belief in the inherent superiority of one’s own ethnic group or culture.  Ex: Yononami(“the humans”): indigenous people in South America  -Cultural “Relativism”: view that considers human interactions and behavior within their own cultural context. Keeping an open mind about a particular group or culture.  Ex: most common form of marriage in the world today- Polygamy-One man married to multiple women  Ex: Na: an indigenous group in China, men go around having “relations” with women. Child views mother’s brother as father figure.  Ex: Efik: Culture in Africa like the women fat; go to fattening room before marriage.  -Fieldwork(data collection): going out into the “field” and studying a culture, spending time in a museum, excavation at a site , analyzing in a lab.   Four Subfields :  1. Linguistic Anthropology- focuses on language/communication. Study social norms of communication within a culture, origin of language, gender speech variation.  2. Cultural Anthropology(Sociocultural)- Learned behavior, distinct among groups; passed down through generations; changes; 5,000 distinct diff cultural groups. (Culture)  3. Archaeology- Studying past human behavior based on the material remains of what they left behind. Two types: academic (study and learn about archaeology) and contract (jobs in archaeology. Have firms like law firms).  4. Biological Anthropology- (aka physical anthropology) biological aspects of humans (race), study of close relatives (primates), fossil records. Study of human biological evolution and human bio-cultural variation.  American Anthropology  -Fronz Boas: set standard for American anthropology- “Father”  “4-field” approach, Biocultural perspective (Wholism), trained 1st generation. -Ales Hrdlieka: started the American Journal of Physical Anthropology  organized scientific society of- American Association of Physical Anthropologists   History of Evolutionary Thought  Charles Darwin : Biological Sciences; published Origin of Species  Idea of Evolution (species change)  Adaptive Radiation : from a single ancestor (species) you can have multiple descendants (species); one common ancestor.  Gradualism: a gradual (slow) change; evolution  Natural Selection : ”Survival of the fittest”. Impact of the environment on living forms.  Middle Ages:  order – Idea that everything can be arranged heiarchaly. There is a natural arrangement of life.  stasis – idea of consistency (things don’t change)  heavily influenced by religious beliefs – “great chain of being”   Examples of Natural Selection  Medium ground Finches o The birds with the larger and tougher beaks survived because of the food source change during a drought.  Peppered Moth o Black colored moth became more common than white during the industrial revolution – predators could see white moths more easily  Antibiotic Resistance o Ex) multidrug-resistant tuberculosis (MDR TB) Methicillin – resistant staph (MRSA)   Heredity  Homunculus – “little man,” in every sperm cell there was a little person that just got bigger  Blending inheritance – Each parent contributes tiny particles that represent different body parts that blend and develop into a human  Cells o prokaryotic – simple life forms. No nucleus. o eukaryotic – nucleus; organelles.  cell types o somatic cells – body, muscles, bones. Body cells. o gametes – sex cells, reproduction  DNA  2 chains of nucleotides (sugar + phosphate + nitrogenous base)  bases (A, G, C, T)  base – pair specificity – bases bind in very specific pattern with each other  replication (growth, development, maintenance, repair) o DNA’s ability to copy itself  Nuclear DNA (nDNA) o Nucleus of every cell (except rbc), 1000’s of genes, “blueprint” template for protein production, homoplasmic (same in every cell)  Mitochondrial DNA (mtDNA) o found in mitochondria o 37 genes (much smaller section of DNA) o assist with mitochondria functions (ATP) o heteroplasimic- not identical in every cell Heredity  gene – sequence of DNA, responsible for cell function o structural – coding for different kinds of proteins, responsible for body structures o regulatory  regulates the expression of other genes (turns genes on and off)  Homeotic (hox) genes – how the body forms tissues and organs. Guides embryological development.  Chromosome – sequence of genes (46 total) Karyotype= layout of an individuals’ different chromosomes. o 23 homologous pairs – chromosomes that carry the same genetic information, code for the same traits, same size, but not identical to each other o autosomes (22 pairs/44 individuals) – carry info of the body (physical characteristics, except for primary sexual characteristics) o sex chromosomes (1 pair/ 2 individuals) – determine the sex of the individual   Cell Division Comparison  Mitosis : Division of Somatic cells  2 daughter cells  identical to each other and the original  diploid  occurs for growth and development, tissue repair, body maintenance  Meiosis : Cell division that produces Gametes  Recombination (crossing over) occurs – the exchange of genetic material between homologous chromosomes during meiosis; creates variation  4 daughter cells  not identical to each other or the original  haploid (half the compliment of DNA=23)  gamete development   Cell Division Mistakes  -Nondisjunction: failure of chromosomes to separate during meiosis, more serious if it happens in autosomes  Sickle cell anemia.  Tay-Sachs, Cystic Fibrosis- both fatal  “Carriers”- if only have one carrier of the allele, passes it on  heterozygote expression- impacts body, carriers have some impact  II. Polygenic Inheritance -“Polygenic traits”- traits coded for genes at more than one locus  Continuous in expression (show a range of expression)  Ex: sin color, eye color, face shape  Melanin production- darkness of skin color  Multiple loci contribute  Codominant alleles   Environmental Influence: environmental influences polygenic inheritance. Ex. height  Pleiotropy : 1 Gene that can influence many traits   Modern Theory of Evolution  Evolution : The change in the genetic frequencies in a trait in a population over time  Production and distribution of genetic variation  Natural Selection  Microevolution : Small scale adaptive changes in a population  Macroevolution : Large scale changes that have resulted in a specific speciation event  Deme (population) : Group of organisms that interbreed regularly and produce offspring.  Gene Pool : entire genetic information of a population  Hardy-Weinberg Equilibrium : Mathematical equation that predicts allele distribution in a population under ideal conditions.   Influence of Allele Frequency  1. Mutation: Change in the DNA sequence; only way for new combination of alleles/ DNA to occur  2. Gene Flow: Movement of alleles between populations  3. Genetic Drift: random change in allele frequencies  Bottle Neck Effect : start out with large genetically diverse population that is suddenly and drastically reduced; variation is lost for future generations  Founder Effect : start out with small population; small group of individuals set out and colonize an area o Ex: Ellis-Van Creveld Syndrome: affects dwarfism and polydactylism; more frequent in Amish population. Recessive allele affects autosomes  4. Natural Selection: Differential reproductive success under specific environmental circumstances  Influences on allele frequencies  Balanced Polymorphism (Heterozygote advantage): Maintenance of 2 or more alleles in a population due to the selective advantage of the heterozygote o Sickle cell allele- strongest in dark areas, recessive allele, must receive 2 copies (homozygotes), alters the shape of blood cells, usually located around another disease Malaria (spread by parasite)-carriers of sickle cell are better prepared or malaria. o Other (Possible) Balanced Polymorphism: o –Tay-Sachs (Ashkenazim)- need two copies of recessive allele, impacts neurological system, and shows signs by 6 months, death by 2-3 years. May gives an advantage against the bacteria that causes tuberculosis. o –Cystic Fibrosis- causes a lot of problems for your digestive tract, but helps against cholera (causes loss of nutrients and dehydration). Human Variation  Hypertension in African Americans: African Americans have higher blood pressure o Founder effect + Natural Selection, High salt retention  Genetic, weight, salt excretion, stress  Research has shown that best response comes from effecting that salt intake-(medicine, diet)   Human Variation  -“Voyages of Discovery”- 1500s-1700s  Monogenism : all humans descended from a single original pair (Adam & Eve), any variation is due to environmental variation  Polygenism : different populations were descendants of different pairs of ancestors  -Early studies (18th-early 19th centuries)  descriptive/classifying different populations of humans  -Mid 19th century:  Biological Determination : the idea that behavioral attributes are associated with biological attribute (intelligence, behavioral morals) Race Common definitions: -species -cultural/ethnic identity -religious identity -physical characteristics - has come to have a negative connotation. “Ethnicity” , “Ancestry” are substitute words for race (which has had negative meanings toward physical differences between races).