studying human society in a cross-cultural perspective
study of the form, function, and social context of language
deals with adaptions, variations, and evolution of human beings
pioneers in primatology, helped support study of common ancestor of humans and chimps
Subfields of biological anthropology
paleoanthropology, human biology, primatology, molecular anthropology-which living primate species share common ancestry; divergence times of different primate groups
What is science?
empirical and self-correcting, experimentation or observation, can be interpreted in different ways, explanations can change based on new evidence
The scientific method
observation+deduction, construct hypothesis, experimentation or analysis, hypothesis supported or refuted.
research design and variables
Independent Variable: impact on another variable. Dependent Variable: may change from independent variable. Control Variable: held constant to test the influence of independent variable on the control variable.
a scientific hypothesis that has been supported by scientific research and evidence. Withstood repeated attempts at rejection
fixity of species
every species was created in the past exactly as it appears today. No new species can be created or become extinct. Species diversity is just 'noise' in the system around an 'ideal type'. Part of religious doctrine from the Middle Ages
great chain of being
all organisms exist in a hierarchical ladder with humans on the top rung.
short geographical timescale
Archbishop Ussher. During Renaissance it was determined through geology, paleontology and astronomy that the universe is ever changing, not fixed.
Natural theologian, determined world began in 4004 BC based on descendants of Adam and Eve.
1627-1705. Distinguished groups of plants and animals by their ability to reproduce with one another.
1707-1778. Systema Naturae, 1735. Binomial nomenclature to classify plant and animals that is still used today.
Comte de Buffon
A.k.a George-Louis Leclerc 1707-1788. "Natural History" in 1749. Emphasized changing universe and changing nature of species.
1731-1802. Darwin's grandfather. Early supporter of evolution.
1744-1829. Species change due to environment. Inheritance of acquired characteristics. First to try to explain HOW
Inheritance of Acquired Characteristics
theory that characteristics developed or adaptions made over an individuals life time could be past on to next generation.
1769-1832. Proposed idea of EXTINCTION to explain the disappearance from the earth of animals represented only by fossils. Theory of catastrophism.
Theory of Catastrophism
theory that geographical changes happen all at once in catastrophic events and not gradually.
1766-1834. "Essay on the Principle of Population" in 1798. Modeling human population growth. Pop. growth is controlled by resource availability, which leads to a struggle for existence.
1797-1875. "Principles of Geology" early 1830's. Theory of Uniformitarianism
Theory of Uniformitarianism
"the present is the key to the past". Assumption that natural processes operating in the past are the same as those that can be observed operating in the present.
Darwin's postulates and evidence for Natural Selection
Work with diversity in finches on the galapagos islands. Natural selection is based on the concept of 'selective breeding', in this case nature does the selecting of what genes are to be passed on.
Alfred Russel Wallace
similar idea to Darwin, there was pop. change overtime. Decided to publish his book On the Origin of Species.
Thomas Henry Huxley
came up with idea to try and explain mode of inheritance, was not logical. Idea that contribution are halved at each successive generation.
Components of the cell
nucleus, mitochondria, ribosomes, DNA
Types of cells
Prokaryotes (all singled-cell organisms) and Eukaryotes (have a nucleus)
Deoxyribonucleic Acid. Double helix structure composed of two complementary strands. Each strand is composed of a sequence of nucleotides with a sugar phosphate backbone. Two strands are connected by hydrogen bonds formed between complementary bases.
For growing and healing. Separated by enzyme called helicase. Unattached nucleotides are attached to the free ends of each strand. Two new strands are formed and replication is completed.
Gene is transcribed into mRNA which is translated into protein.
discrete structures composed of DNA and protein. How DNA is organized in the cell. Chromosomes occur in pairs. Inherit one member of each pair from mother and father.
Total chromosomal compliments of an individual, humans have 46.
Simple cell division: creates 2 identical daughter cells.
cell division in specialized cells in ovaries and testes. Involves two divisions and results in 4 daughter cells. Develop into gametes. Recombination (crossing-over).
The entire genetic make-up of an individual or species. About 3 billion nucleotide bases.
unit of heredity in a living organism.
non-coding regions (edited out after transcription).
passed on from mother to both sexes. No introns or repetitive DNA. Does not recombine. Preserves a lot of information about ancestry because it preserves better than DNA.
DNA can be extracted from hair, tissues, blood, feces, saliva, bone
Pea plants. Dichotomous variation
Mendel's postulates for inheritance
1. Hereditary characteristics are controlled by particulate unit factors that exist in pairs in individual organisms.
2. When an individual has two different unit factors responsible for a characteristic, only one is expressed and said to be dominant to the other, which is said to be recessive.
3. During the formation of gametes, the paired unit factors separate, or segregate, randomly so that each sex cell receives one or the other with equal likelihood.
4. During gamete formation, segregating pairs of unit factors assort independently of each other.
genes on the same chromosome should segregate together and find themselves in the same sex cells.
makes possible the independent assortment of linked genes.
the modern synthesis
controlled by alleles at only one genetic locus. In contrast to polygenic traits.
ABO blood type
aggulation: what happens when you don't get the right blood type. Different blood types has to do with different anti-bodies in the blood.
point mutation: when a single base in a gene is changed (sickle cell)
insertion mutation: addition of one or more base pairs in the DNA
deletion mutation: x-linked disorders-hemophilia -color blindness
sickle cell anemia
point mutation. helps fight malaria
recessive alleles, passed on and carried by women, only men express them.
result from the combined action of more than one gene with multiple alleles.
one gene has mult. phenotypic effects. Ex: achondroplasia, shortened limbs, larger head.
measures the proportion of the phenotype that can be attributed to the genetic factors. variability caused by genes divided by (variability caused by genes + variability caused by environment).
definition of evolution
change over time.
a measure of the relative frequency of an allele at a particular genetic locus in a population.
AA Aa aa
when the trait is expressed.
Hardy-Weinberg equilibrium (and its assumptions)
Null hypothesis: evolutionary forces are not at work on a population. p squared + 2pq+q squared
Microevolution vs. macroevolution
micro: small changes occurring within a species, such as a change in allele freq.
macro: changes produced only after many generations
exchange of genes between populations. migrating and then mating
changes in allele frequencies (evolution), produced by chance. Small populations drift more rapidly than large populations, as chance events have more of an effect.
Bottleneck. reduction in variation. Rare alleles can become more common.
maintain a genetic polymorphism with in a population.
selecting for greater or lesser frequency of a given trait in a population
maintains a phenotype by selecting against deviations from it.
the number of offspring an individual produces and rears to reproductive age
an individual's total genetic contribution to the next generation, through one's own offspring and those of relatives.
Sexual selection (and its two components)
1. Struggle between males to gain access to mates.
2. Struggle by a female to choose the right mate.
phenotypic and genotypic variability in living populations of modern Homo sapiens.
an interbreeding group of organisms that is identifiable with in a particular species.
measurement of different aspects of the body
used to define and explain racial variability
Racial grouping: caucasian, mongolian, ethiopian, american, malayan.
Scientific racism helped to justify many bad things.
Transformed race from biological into sociological concept. !Physical variation did not necessarily coincide with racial categories.
max width divided by max length
not a good indicator of race
present in Asian and American populations.
Study by Richard Lewontin and colleagues (1972)
study of genetic variation. Findings: 85% of total variation in world was present with in local groups. No natural subdivision of humans into groups, as variation is continuous.
geographical distribution of a trait or allele
2 or more alleles in a population. role of genetic drift on frequency of O allele in Americas.
Genetic drift and polymorphisms
When Asian populations migrated to the Americas they brought a higher percentage of O blood type so O is more common in those populations.
Gene flow and polymorphisms
There is gene flow between groups in America. gene flow from European and Af. Am. pops. was sex-biased. Can trace traits back to common ancestor to understand migration patterns and modern human origins.
Duffy blood group
Present in Af. Am. pops. (4%-26%). Largely absent in African populations.
Phylogey of modern human populations
Natural selection and polymorphisms
some traits advantages some not. But both are still present in a population.
lactose tolerance is advantages in some pops. and not others. Ex. people who have cattle.
Maternal-fetal incompatibility complex
functional modification of structure, physiology, or behavior of an organism that increases fitness in a particular environment.
Types of non-genetic adaptations
adjustments to the environment cultural, behavioral, acclimatization, adaptability
Difference between genetic and non-genetic adaptation
genetic is over many generations and non-genetic is a single individual
physiological responses to change in environment that occurs during an individual's lifetime
types of environmental stressors
solar radiation, thermal stress, altitudinal stress, heat and UV stress,
high altitude adaptations
cultural: oxygen mask
behavioral: walk slower
acc: hyperventilation, increased blood flow, increased Hb
adapt.: barrel chests, larger hearts, 20-30% larger lungs
hypoxic ventilatory response
HVR high in lowlanders, low in Andeans, like acclimatized lowlanders. HVR is high in Tibetans, similar to lowlanders and 2 times that of Andeans
hemoglobin concentration of number of red blood cells.
body mass greater in pops that live in colder climates as mass increases relative surface area decreases, meaning heat los is reduced. Lost heat=lost energy, so being big is advantageous in cold environments.
colder climates= shorter appendages
warmer climates=longer appendages
in warmer climates surface area can be increased while keeping mass constant by assuming a more linear form
Skin color and solar radiation
dermis: thick inner layer of collagen, hair follicles
epidermis: thinner outer layer, 95% epithelial cells 5% pigment cells
pops. with darker skin in tropical regions, lighter skin color as you move away from the equator
higher risk with lighter skin because more UV rays get past skin.
Breakdown of folate
UV radiation breaks down folate. Folate is involved in DNA synthesis, sperm production, red blood cell formation, neural development. Can cause developmental problems during pregnancy
Vitamin D and rickets
Lack of vitamin D can lead to rickets which can cause bow legged bones, deformation of pelvis with childbirth problems, major problems in early 20th century with urban children and darker skinned children in America.