Term | Definition |
what is life/alive | maintains homeostasis
reproduction
using/metabolizing energy
produces waste |
seven characteristics of life | cells
ordered complexity-not chaotic
sensitivity-respond to stimuli
growth,development,reproduction
energy utilization
homeostasis
evolutionary adaptation |
living systems show hierarchal organization | -cellular level
-organismal level
-populational level
-ecosystem level
-biosphere |
emergent properties | more than the sum of its parts, not additive
novel properties arising from the way in which components interact
-life
--result from interaction of components
--cannot be deduced by looking at parts themselves |
3 domains of life | archae
bacteria
eukaryote |
deductive reasoning | uses general principles to make specific predictions |
inductive reasoning | uses specific observations to develop general conclusions |
scientific method | the systematic approach to understand natural world
-observation
-hypothesis formation
-prediction
-experimentation
-conclusion |
hypothesis | possible explanation for observation
-must be tested to determine its validity
-often tested in many different ways
-allows for predictions to be made
-repetitive/iterative
--can be changed and refined with new data |
independent variable | condtion |
dependent variable | measurement |
controlled varaibles | variables that are not changed |
qualitative data | -descriptions
-data observed, but cant be measured
ex) colors, smells, beauty |
quantitative data | -number
-measured
ex) length, height, time |
scientific theory | broad and strong explanation-supported by lab books of scientific research with minimum influence of human bias
ex)cell theory |
genetic variation | the differences in alleles of genes found within individuals of a population |
evolution | descent with modificiation
change over time |
inheritance of acquired characteristics | changes that occur during lifetime are passed down to children
ex)long neck giraffe |
how to monitor how populations change | look at changes in allele frequencies of a gene from one generation to the next |
population genetics | the study of the properties of genes in populations |
how to directly assay genetic variation within populations | electrophoresis
RFLPs--exploits variations in homologous DNA sequences
sequencing entire genomes
SNPs--a variation in a DNA sequence |
hardy Weinberg equilibrium requirements | no mutation
no immigration or emigration
mating is random
the population size is very large
no selection occurs |
allele frequencies | a measure of the occurrence of an allele in a population |
genotype frequencies | a measure of the occurrence of a genotype in a population |
reproductive success | how long an individual survives
how often it mates
how many offspring |
frequency dependent selection | favors either rare or common phenotypes |
oscillating selection | favored phenotypes changes as the environment changes |
hypothesis driven science | makes a tests predictions
find out which general principles are true by systematically testing alternative proposals and rejecting them if untrue from observations |
test experiment | one variable is altered in a known way to test a particular hypothesis |
control experiment | the variable is left unaltered |
reductionism | analyzing simple and basic physical mechanisms to explain complex phenomenons |
theory | a proposed explanation for some natural phenomenon (based on some general principle)
the body of interconnected concepts(supported by scientific inquiry and experimental evidence) |
the cellular level | atoms join together to create molecules whice are assembled into organelles which are within cells |
the organismal level | tissues(groups of similar cells that act as a functional unit)
organs(groups of tissues)(brain)(structural and functional unit)
organ systems(groups of organs)(nervous system) |
the populational level | population(group of organims of the same species living in the same place
species(populations of a specific type of organism)(able to interbreed) |
biological community | all populations of different species living together in one place |
the ecosytemal level | ecosystem(populations interact and with their environment) |
the biosphere | entire planet |
natural selection | mechanism for evolution |
malthus | populations increase by a multiplying factor
how populations grow |
homologous | same evolutionary origin
different structure and function |
analogous | similar functions
different evolutionary origin |
macroevolution | speciation/evolution of new species form old species
evidence: homologous and analogous traits-similar embryonic development |
microevolution | evolutionary change WITHIN species |
mechanisms/modes/forces of evolution | forces that change the genetic structure of a population
mutation
natural selection
gene flow/migration
genetic drift(random)
recombination |
mutation | an allele changes to another allele thereby altering the gene
only source of new alleles
create and maintain new generic variation
rare |
natural selection | differential survival and reproduction of individuals due to differences in phenotype/traits |
gene flow/migration | movement of genes between population |
genetic drift(random) | random changes in allele frequencies
-natural disasters,large fatal diseases
-reduces genetic variation in small populations
-founders effect and population bottleneck |
recombination | combination of genetic material from two different gametes (sexual selection)
-offspring differ from parents(crossing over and independent assortment) |
point mutation | single base in DNA sequence is changes
most common type of mutation evolutionary
not all bad |
selective agent of NS | environment |
artificial selection | occurs fast with many changes and can produce major evolutionary changes
humans as selective agent
ex: faster horses and sweeter apples |
Lamarck's view | keep stretching necks throughout lifetime and then pass this on to babies #false |
Darwin-Wallace view | only giraffes that can reach taller leaves survive so long necked trait is favored and is reproduced |
natural selection operates on the | individual/the phenotype
(already present) variation -which is hereditary |
evolution acts on the | population |
small populations result from | population bottleneck and founders effect |
population bottleneck | sudden decrease in population size |
founders effect | few pioneering individuals colonize new region
ex)amish |
non-random mating | the probability that two individuals in a population will mate is not teh same for all possible pairs of individuals
ex)having a certain type to date |
dissasortative | the reproductive pairing of individuals that have traits more dissimilar than would likely be the case if mating were random |
assortative | the reproductive pairing of individuals that have more traits in common than would likely be the case if mating were random |
inbreeding | breed closely related people or animals especially over many generations |
inbreeding depression | the reduced biological fitness in a given population as a result of inbreeding |
balancing selection | multiple alleles are actively maintained in the gene pool of a population, natural selection will favor uncommon allele so the two alleles remain balanced in amount-depend on each other |
disruptive selection | extreme values favored over usual population |
intersexual selection | both individuals are involved in choosing a mate |
intrasexual selection | two members of the same sex compete for mate |
directional selection | a single phenotype is favored |
stabilizing selection | mean values are favored |
sexual dismophism | difference in size and appearance
ex)female spiders are bigger than male spiders |
fixed creationism | before darwin
organisms are created as they are and remain in the same form since the beginning
no new organisms |
Linneaus | binomial nomenclature
taxonomy
scientific name |
gradualism | James Hutton-geology
earth is old and ever-changing
the accumulation of small changes
extreme of evolution
standard view for a long time |
lamarke | coined the term "evolution" -process of changes of life over long periods of time
stupid giraffe theory though |
three conditions of natural selection | genetic variation exists in population
leads to differences among individuals in reproductive success
must be genetically transmitted to next generation |
biogeography | how animals and plants are distributed
wallace=founder |
convergent evolution | unrelated lineage, similar traits now
environment selects traits(similar environmental pressures)
ex)birds and bats |
homologous traits | evolutionary descent from common ancestor
ex)bats and human and whale bones |
analogous traits | similar due to common adaptive function
ex) wings |
species concept | ernst mayr
groups reproductively isolated and potentially or actually interbreeding |
ecological species concept | where a species adapted to a niche in the environment |
phylogenetic species concept | the smallest set of organisms that share an ancestor and can be distinguished from other sets |
evolutionary species concept | a species=maintains its identity from other such lineages/species and has its own evolutionary tendencies and historical fate |
galapagos finches | evidence of NS
corrrespondance of beak shape and food gathering shows finches diversified and adapted aka NS |
sympatric speciation | speciation within same area-no geographical seperation |
allopatric speciation | geographic seperation causes speciation |
speciation | creation of new species that can exchange genes/interbreed and create futile offspring
evolutionary process by which new biological species arise
-form from isolation, environmental change |
reproductive isolating mechanisms | prevent genetic exchange between species
random changes/genetic drift + adaptation can lead to
pre zygotic
post-zygotic |
pre-zygotic isolating mechanisms | prevent formation of zygote
temporal, behavioral, ecological, mechanical |
post-zygotic isolating mechanism | prevent normal development into reproducing adults |
reinforcement | natural selection increases reproductive isolation |
homogenization | prevent speciation from ocurring |
adaptive radiation | species + new/changed environment + many resources + few competing species
ex) Darwin's finches |
key innovation | the evolution of a new trait that allows individual to use previously inaccessible parts of the environment |
punctuated equilibrium | long periods of stasis followed by relatively rapid change
an extreme of evolution
stabilizing and oscillating selection is responsible for stasis |
a reverse in environmental conditions = | a reverse in selection pressure |
"evolutionary change occurs in the ___ of beak sizes in the ____ generations" | frequencies
subsequent |
subspecies | within a single species, individuals in populations that occur in different areas may be distinct from one another |
ecological isolation | live or dwell in different areas ex)tree lions
pre |
behavioral isolation | select mates after elaborate courtship display ex)blue footed boobies
need to do ritual well to be selected or at all
pre |
temporal isolation | species of wild lettuce, but one flowers in the spring one in the summer
pre |
mechanical isolation | structure of copulating organs may not be compatible ex)pollen may not reach the right part
pre |
prevention of gamete fusion | eggs and sperm in water not fuse with other species
pre |
hybrid inviability | hybrids dont develop
hybrids will not survive into adulthood they will become weak or sterile or abnormal sex organs
post |
anagenesis | when population of entire species changes on genetic level with out a split
-ancestral population goes extinct |
cladogenesis | species splits into two genetically distinct populations adapted to different ecosystems and/or survival strategies-both species may survive types of speciation |
adaptive radiation causes | pioneering a new habitat containing few competing organisms
mass extinction wiping out competitors
-surviving forms radiate to occupy niches left behind |
hybrid sterility | hybrids may develop, but they are not fertile |
hybridization | the process of combining different varieties of organisms to create a hybrid |
types of qualitative data | ordinal-order, scales 1-5
nominal-lables |
types of quantitative data | interval-numeric scale
ratio-measurement scale |
Darwinian fitness | It measures the reproductive success of an entire population of organisms. You can not relate Darwinian Fitness to a single organism. |
part of Darwin's theory on the origin of species | All organisms are related through descent from a common ancestor.
A population can change over time if individuals that posses certain traits leave more offspring than others.
There are always variations within a given population. |
developmental homology | organism that develop similarly in the womb-evidence of common ancestors |