Biology Unit 7: Evolution & Classification
linnaeus' system of classification
(domain - ) kingdom - phylum - class - order - family - genus - species
history of life development
1. earth 2. atmosphere/ocean 3. first bacterial cells 4. oxygen 5. first eukaryotic cells 6. multicellular organism (algae) 7. invertebrate (jellyfish, simple worms) 8. vertebrate (jawless fish) 9. land plants 10. land animals (insects) 11. amphibians 12. reptiles 13. dinosaurs 14. birds 15. mammals 16. flowering plants 17. mass extinction (including dinosaurs) 18. monkeys 19. hominids 20. humans
biochemical evidence process
1. similar dna = similar protein = similar function 2. dna mutations at certain rates 3. mutations -> variations 4. populations begin to incorporate new alleles (due to mutations) into dna 5. when organisms interbreed, their dna continue mutation at same rate 6. dna and proteins become less similar as time pass
4 things that mitochondria and chloroplasts both have (endosymbiont evidence)
2 membranes own DNA ribosome reproduce by binary fission
fitness
ability of an individual to survive and reproduce in environment
embryonic development
all vertebrate embryos follow common developmental path due to common ancestry
hardy-weinberg equilibrium
alleles in population remain constant if: - no mutation - no migration - no selection - random mating - large population impossible in reality -> alleles in population change
urey and miller experiment result
amino acid and carbon compounds spontaneously arose (not cell itself)
half life
amount of time needed for radioactive elements to decay (*practice calculation*)
how to read phylogeny tree
ancestor: base, longest branch most recent: top, shortest branch closely related: separated by few branches
3 domains of living things
bacteria, archaea, eukarya (protista, fungi, plantae, animalia)
how do new species form?
begin with isolation
difference between phylogenetic tree and cladogram
both show evolutionary relationship between species only phylogenetic tree represent evolutionary time and amount of change
natural selection
cause of evolution (survival difference) happen by environment's action organism with favorable genes reproduce more then become more common
co-evolution
change in genetic composition of one species in response to genetic change in another
microevolution
changes in gene frequency in population from one generation to next
4 patterns of evolution
convergent evolution, divergent evolution, adaptive radiation, co-evolution
invertebrates' phylum
coral- cnidaria earthworm- annelida sponge- porifera flatworm- platyhelminthes starfish- echinodermata grasshopper- arthropoda snail- mollusca crab- arthropoda
macroevolution
descent of different species from common ancestor over many generations
relative age
determined by its position in sedimentary rock
geological age
determined by radiometric dating
cladogram
diagram that act as hypothesis that show our best guess at how organisms are related
molecular clock
dna and proteins more time since divergence - more mutation, different dna less time since divergence - less mutation, similar dna
natural selection
environment selects organisms with optimal traits to reproduce
plantae
eukaryote cell walls of cellulose/chloroplast multicellular autotroph ex. moss, fern, flowering plants
fungi
eukaryote cell walls of chitin mostly multicellular (or unicellular) heterotroph ex. mushroom, yeast
protista
eukaryote cell walls with cellulose/chloroplast mostly unicellular (or colonial/multicellular) autotropch/heterotroph ex. amoeba, paramecium, slime mold, giant kelp
animalia
eukaryote no cell walls/chloroplasts multicellular heterotroph ex. sponge, worm, insect, fish, mammal
endosymbiotic theory
eukaryotic cells formed from symbiosis among several different prokaryotic organisms
vertebrates' class
fish- osteichtyes chicken/bird- aves frog- amphibia snake- reptilia shark- chondrichthyes bat- mammalia lamprey- agnatha
competition
for limited resources (not all survive)
index fossil
fossil made of easily recognized species that existed for short time but wide geographical range used to compare relative fossil ages
5 evolution evidence
fossils embryonic development homologous structures vestigial structures biochemistry
binomial nomenclature
handwriting: underline typing: italicize
malthus' theory
human population is capable of growing faster than food supply increase -> false
artificial selection
humans selecting useful variations out of ones that nature provided
biochemical evidence
if 2 organisms have similar dna, then they: - have similar proteins - are related - share common ancestor
what happens to organisms' complexity?
increase over time
common misconceptions of evolution
individual organisms don't evolve (populations do) organisms can't decide to evolve (either have adaptation or don't) evolution doesn't happen in 1 generation (requires many) humans did not evolve from monkeys (share common ancestor)
punctuated equilibrium
long periods of equilibrium followed by short/rapid bursts of change
6 kingdom classification system
monera (eubacteria, archaebacteria) plantae (non-vascular, vascular) fungi protista animalia (invertebrate, vertebrate)
4 factors that cause variation
mutation, environment, recombination, random combination of gametes at fertilization
why are scientific names necessary?
names vary in different locations scientists speak different languages make communication easier avoid ambiguity
do all species change?
no: depends on environment
convergent evolution
not-closely-related organisms evolve similar traits as they both adapt to similar environments
divergent evolution
one species develop into 2+ species over long period of time
speciation
over time favorable adaptations accumulate and new species results
6 requirements of natural selection
overproduction, competition, variation, adaptation, natural selection, speciation (not always)
hardy-weinberg equation
p^2 + 2pq + q^2 = 1 p + q = 1 (p= frequency of dominant allele, q= frequency of recessive allele) (*practice*)
species
population of organisms that can successfully breed and produce fertile offspring
overproduction
produce more offspring than needed to maintain species
monera (eubacteria, archaebacteria)
prokaryote cell walls with/without peptidoglycan unicellular autotroph/heterotroph ex. streptococcus, e.coli / methanogen, halophile
key points to remember in life history
prokaryotic cells -> eukaryotic cells reptiles -> amphibians cells -> oxygen dinosaurs -> birds
adaptive radiation
rapid speciation from common ancestor in nearby but distinct environments very fast only in few generations ex. galapagos finches
fossil dating
relative age, geological age
4 types of isolation
reproductive, geographic, temporal, behavioral
reproductive isolation
results from barriers to successful reproduction
behavioral isolation
results from different mating behavior
geographic isolation
results from physical separation
temporal isolation
results from timing separation
taxonomy
science of naming and classifying organisms
darwin's theory
similar animals live in different environments environmental disturbances give impact on creatures
homologous structures
similar structures with different functions
gradualism
slow gradual changed over time
adaptation
some traits give favorable advantage to obtain limited resources
disapproved theories about life
spontaneous generation: living things arose spontaneously from non-living matter biogenesis: life gave rise to more life
3 types of natural selection
stabilizing selection (ex. human birth weight) directional selection (industrial melanism of moths) disruptive selection (ex. beetle color) (refer to graph)
analagous structures
structures in different species that have same function but have evolved separately
vestigial structures
structures that lose function but remains ex. human's tailbone, salamander's eyes, limb's pelvic bone
phylogeny
study of evolutionary relationships among organisms to scale of evolutionary time
why is rna before dna?
suspected to be first genetic material less complicated can form in water has enzymatic properties
gene pool
total collection of alleles within population
fossil
traces of once living species in sedimentary rocks trapped in amber/lice
lamarck's theory
usage of feature determines if it is strengthened over life time children may inherit parent's acquired traits -> false
variation
within population
