Biological Anthropology Exam #1

EVOLUTION

change in allele frequencies over time

ANAXIMANDER

• humans are descendants of fish

• natural causes for biological/earthly phenomena

PLATO

fixity of species (no change)

ARISTOTLE

great chain of being - hierarchy with humans closest to god

AL-JAHIZ

• Iraqi polymath

• evolutionary theory similar to natural selection

• environment influences traits

LI SHIH-CHEN

• chinese naturalist and chemist

• organisms are influenced by environment

• binomial and hierarchy system similar to modern

• used empirical evidence

JOHN RAY

• defined species - organisms that can reproduce together

• defined genus - similarities between species

COMTE DE BUFFON

• migration is due to changing environments

• external environment is important to biological change

JEAN LAMARCK

theory of inheritance of acquired characteristics - organisms can pass on traits acquired during their lifetime to their offspring (i.e., giraffes’ long neck)

GEORGES CUVIER

• fossils and layers of the earth to show change

• catastrophism - environmental catastrophes cause extinctions which explains fossil variation

CHARLES LYELL

• father of modern geology

• mentor of darwin

• uniformitarianism - geological forces of change persist today

HMS BEAGLE

brought darwin to south america, indian ocean, and south africa

MALTHUS

• predicted exponential human population growth in relation to available food supply

• struggle for existence and competition

• inspired by darwin

FITNESS

reproductive success

HUXLEY

• supporter of Darwin

• humans have a common ancestor with apes

HOMOZYGOUS

2 copies of the same genetic factor

HETEROZYGOUS

2 different genetic factors

PARTICULATE INHERITANCE

genes are passed down instead of offspring being a blend

CHROMOSOME

tightly wound nuclear DNA strands (chromatin) that condenses during cell division

LOCUS

gene’s location on the chromosome

KARYOTYPE

collection of one’s chromosomes (23 pairs; 46 total)

CHROMATID

½ of a chromosome

AUTOSOMES

pairs 1-22 of chromosomes

SEX CHROMOSOMES

the 23rd pair of chromosomes, XX or XY

SOMATIC CELLS

body tissue components (46 chromosomes)

GAMETES

sex cells (ova and sperm; 23 chromosomes each)

ZYGOTE

union between sperm and ovum

DIPLOID

two sets of chromosomes (46)

HAPLOID

single set of chromosomes (23)

NUCLEOTIDES

building blocks of DNA

TRANSFER RNA (tRNA)

matches mRNA to complimentary bases to create an exact copy; also brings amino acids to start making proteins

GENETIC CODE

64 codon sequences using 20 amino acids.

EXONS

contains codons that code for proteins; is transcribed and translated

INTRONS

no coding; gets cut out when mature mRNA is created.

MATURE mRNA

final blueprint for protein synthesis after splicing.

SYNONYMOUS MUTATION

mutation that results in no change to the final amino acid

CODOMINANCE

both alleles in heterozygous condition are fully expressed; one is not dominant over the other (i.e., AB blood type)

STRUCTURAL GENES

code for polypeptide change

REGULATORY GENES

growth of an organism’s body

POPULATION GENETICS

changes in frequencies of alleles, genotypes, and phenotypes across generations

MUTATION

creation of new alleles

ASSORTATIVE NON-RANDOM MATING

individuals with the same phenotypes mate more frequently than expected under random mating

DISASSORTATIVE NON-RANDOM MATING

individuals with different phenotypes mate more frequently than expected under random mating

POPULATION

group of organisms potentially capable of successful reproduction

GENE POOL

sum of all alleles carried by members of a population

GENETIC EQUILIBRIUM

no change in allele frequencies

HARDY WEINBURG EQUILIBRIUM

conditions where genetic equilibrium is met; no evolution; random mating required

STABILIZING SELECTION

maintains phenotype by selecting against deviations (one = best)

DIRECTIONAL SELECTION

one extreme trait is favored (skewed towards the best)

DISRUPTIVE SELECTION

maintains the extremes of the population (two extremes = bests)

POPULATION BOTTLENECKS

population's size is reduced by a random event, such as a natural disaster leading to a loss of genetic diversity (genetic drift)

FOUNDER EFFECT

when a group of a population is separated from the larger population (genetic drift)

MICROEVOLUTION

small changes in a species

MACROEVOLUTION

large changes over many generations leading to speciation

SPECIES (BIOLOGICAL)

groups of interbreeding natural population which are relatively isolated from other such groups

SPECIES (ECOLOGICAL)

a group exploiting a single ecological adaptation

SPECIES (EVOLUTIONARY)

evolutionary lineages (common ancestor) with a unique identity

SPECIES (MORPHOLOGICAL)

based on anatomical similarities

PREMATING REPRODUCTION ISOLATION MECHANISMS

• habitat isolation

• behavioral isolation

• mechanical isolation

POSTMATING REPRODUCTION ISOLATION MECHANISMS

• sperm-egg incompatibility

• offspring sterility

CLADOGENESIS

speciation with splitting on the cladogram

ANAGENESIS

speciation without splitting on the cladogram

ALLOPATRIC SPECIATION

speciation due to complete geographic isolation (can lead to founder effect or bottleneck)

PARAPATRIC SPECIATION

speciation due to partial geographic isolation (overlap territory = hybrid zone)

SYMPATRIC SPECIATION

speciation in the absence of geographic isolation (rare)

NICHE

how a species interacts with the environment, other spies, and resources

ADAPTIVE RADIATION

when an organism diversifies to fill many available niches

GRADUALISM

evolution proceeds through accumulated small changes

PUNCTUATED EQUILIBRIUM

evolution proceeds through long periods of stasis and rapid periods of change

SYSTEMATICS

study of the diversity of life and the relationships and all hierarchical levels

ANALOGY/HOMOPLASY

shared trait among species that was NOT present in a common ancestor (i.e. flying)

HOMOLOGY

• shared trait among species that was present in a common ancestor

• derived = synapomorphy

• ancestral = symplesiomorphy 

RACE

• genetically distinct and usually geographically isolated (biology)

• “subspecies” (zoology)

• originally used to described domesticated breeds

LINNAEUS

5 groups/races; glorifies europeans and denigrates POC; binomial system of classification

SAMUEL MORTON

eugenics; used to justify the indian removal act

ANTHROMETRY

pseudoscience used to measure the proportions of the human body

EARNEST HOUSTON AND ALEŠ HRDLIČKA

tried to show that Black people were more similar to apes than white people; stereotypes of Black criminality and athleticism

FRANZ BOAS

• fought racial typologies

• founder of modern academic anthropology

• emphasized environmental adaptations > genes

CARLETON COON

states that Europeans evolved first (empirically false)

WILLIAM COBB AND CAROLINE BOND DAY

Black scholars who fought against eugenics; focused on evolution over classification

RICHARD LEWONTIN

studied genetic variation within/between humans (most found within populations of one race; least found between races)

EPIDERMIS

thin tissue layer @ the surface of the skin

• sweat glands

• protective and non protective

DERMIS

innermost, thickest layer of skin

• thick collagen fibers

• blood vessels

• nerve endings

• hair follicles

• glands

KERATINOCYTES

protects skin against water loss and abrasion

MELANOCYTES

produces melanin; equal number in all humans (only differs in number, spacing, and size of melanosomes aka pigmet organelles)

HEMOGLOBIN

blood protein; pink

KERATIN

hair/skin protein; yellow-ish

MELANIN

main skin color determinant; dark brown

DARK SKIN

more melanin production

LIGHT SKIN

less melanin production

FRECKLES

localized melanin production

POLYGENIC TRAIT

trait impacted by 2 or more genes

ULTRAVIOLET RADIATION (UV)

causes DNA damage in high exposure; most extreme @ the equator

STABLE POLYMORPHISM

2 or more different phenotypes in a population are maintained

BERGMANN’S RULE

larger bodies sizes arise from colder habitats

ALLEN’S RULE

extremities tend to be longer in warm climates to dissipate heat

PLEIOTROPIC TRAIT

2 or more traits impacted by 1 gene