biological anthropology week 2
evolution - most fundamental of all biological processes
humans evolved from species living 6-8 million ya
humans don’t share common ancestor w other primates
theory - something that has been tested and has evidence to support
theory of evolution supported via lots of genetic evidence
species created and never changed (early idea in middle ages)
opposes theory of biological evolution
ancient greeks
first efforts to understand natural world and humans role in it
aristotle
first known life classification
immutability of species
immutability - that which does not change over time
he taught sun and planets existed in series of concentric spheres revolving around earth
copernicus
challenged idea earth was at center of UNIVERSE
galileo
supported idea universe was place of motion and sun is at center
john ray
concept of species
groups of plants/animals could be deciphered from others by their mating ability
reproductively isolated - organisms of a single category (species)
genus - species that share characteristics
carolus linnaeus
est. basis of taxonomy
taxonomy - basis of classifying plants and animals
est. binomial nomenclature
two terms used to classify species (ex. Homo sapiens)
root of modern science
rediscovering greeks and romans
bettering sense of time and cultural variation (period of realization)
study of human anatomy (ex. cadavers)
global exploration
grab piece of life for study when unfamiliar
navigation via star study improved
mapping (cartography) expanded with better detail
european nationalism
road to darwinian revolution
comte de buffon - accepted notion of biological change
georges cuvier - catastrophism
catastrophism - earth’s geography formed from short lived violent events (ex. volcanic eruptions, earthquakes)
jean-baptiste lamarck - theory of inheritance of acquired characteristics
inheritance of acquired characteristics - traits an organism learns in its lifetime can be passed down to offspring
uniformitarianism - theory that same gradual geological process today operated in the past
james hutton (1726 - 1797)
charles lyell (1797 - 1875)
darwinian revolution
charles darwin
voyage on hms beagle
southern hemisphere 1831-1836
the galapagos
variations of tortoise
finch variation
finch beaks adapted for different skills
opening seeds, nuts, feeding nectar, etc
adaptive radiation
biogeography
natural selection
Darwin’s Finches
different finches on different islands due to natural selection
birds of common ancestry adapted to environment
adaptive radiation - evolutionary diversification of single species into many to best fit their environment
refining theory of evolution via natural selection
obs 1 - all organisms have potential for boom in growth
obs 2 - populations roughly stable
deduction 1 - must be struggle for existence
obs 3 - nature full of variety
deduction 2 - some variations favored over others
natural selection
trait in question must be inherited
trait in question must show variety across life
environment must exert pressure on the trait
Fitness, population, mutation
fitness - ability to survive and pass on genes to next gen
population - amount of a species
mutation - something new in genetic material
Alfred Russel Wallace (1823-1913)
independently “discovered” natural selection
wrote letters/conversed with Darwin
Thomas Malthus
author of essay inspiring darwin & wallace regarding natural selection
argued presence of limits to human population growth
argued tendency of animal populations to go up while resources go down
population size is controlled by resource availability
gregor mendel
founder medelian genetics
experiments with particulate inheritance
discovered dichotomous variation
developed postulates of inheritance
involved plant colors, pea types, etc
selective breeding
practice where specific breeds of plants/animals are crossed to produce specific/desired traits
those WITHOUT desired traits not allowed to breed
mendel’s postulates (Laws of Inheritance)
hereditary traits are determined by units (genes) that come in pairs of alleles, one from each parent
mendel’s law of segregation
REVIEW
mendel’s law of indpendent assortment
REVIEW