Please enable JavaScript.

Coggle requires JavaScript to display documents.

Evolution (Darwinism Challenges on Tradition (Aristotle (viewed species as…

- - - - Fossils: the remains of organisms form the past that have been molded on a rock
      - strata: new layers of sedimentary rock cover older ones and get compressed together into layers of rock.
  - - - Urged Darwin to publish his findings before someone else beat him
  - - - characteristic all species share
- - - - resembled species lving on South America
      - some species were only found on Galapagos
    - - similar but different species
      - each were suited for their environment
      - adaptations:inherited characteristics that help organisms survive/reproduce in specific environments
      - Natural Selection:organisms that have certain inherited traits tend to be able to survive/reproduce vs those who lack certain traits
        
        New species can arise from adaptations to a changing environment
        
        Individuals do not evolve/populations do
        
        can only amplify/diminish characteristics that differ in environment
        
        3 key points
        
        natural selection is a process of editing not creating
        
        natural section depends in time and place
        
        species capable of producing new generations quickly evolution by natural section can occur rapidly
  - - - organisms are suited for their environment
      - Unity of life
      - descent with modification=diversity of life
    - - Darwin viewed the line of ancestors as a family tree
      - Each branch representing a new species related to the one it branches off of
      - shows extinct species
    - - Artificial Selection:method human use to modify certain species a specific way
      - Observation 2: All species can produce more offspring that can survive/reproduce in their environment
      - Inference 1: Individuals that inherit the better survival traits will give them a higher probability of having more offspring that survive vs the others
      - Observation 1: members of population vary in inherited traits
      - Inference 2: unequal abilities to survive/reproduce will accumulate favorable traits
      - natural selection=patterns of evolution
      - Artificial Selection=human modification
- - - - Bacteria can be resistant to multiple antibiotics, b/c they can exchange genes with members of their own/other species
      - Bacteria became resistant to the new techniques/antibiotics created by researchers
  - - - similar structures grown out of different functions
    - - all species share a genetic code but have very different functions
      - some homologous gene developed a new functions
      - some are still there but have no function
    - - hypothesis that summarizes a pattern of descent
      - help see what species are related and have diverse lineage
      - supported by many other forms of data like DNA sequencing, and anatomical
      - useful for making predictions
    - - independent evolution of similar features in different species
      - analogous:features that share similar function but do not have common ancestry
        
        due to different species adapting to the same environment
      - another form of evolution
  - - - eventually all the masses separated and distributed species all over Earth
- - - - Chromosomal changes that delete/disrupt/rearrange are harmful
      - if Genes stay together during a change in location then its not harmful
      - errors in meiosis
        
        large supilication may be harful/small ones can be okay
        
        non-harmful duplication's can pile up for years and produce an expanded genome with new genes with new functions
    - - mutations are lower in plants/animals because they have slow reproduction rates
      - mutations are at slower rate in prokaryotes/viruses but have much higher rate of reproduction= mutations can reproduce quickly
        
        viruses
        
        contain RNA=higher mutation because host usually lacks RNA repair
        
        drug cocktails help fight viruses from being able to become ressistant to specific drug
    - - mutaions cause new allels to appear
      - not all mutations are harmful
      - piont mutaion: a single change on a nulceotide base
      - neutral variation:differences on DNA that do not cause advantages/disadvantages
    - - generic variations results from the offspring parents
      - sex shuffles allese randomly to produce individula geneotypes
        
        idependent assortment of cromosomes
        
        fertilization
        
        crossing over
- - - - q=recessive allele
      - p=Dominant allele
  - - - No natural selection
      - Super large population size
      - no gene flow
      - random mating-inbreeding
      - No mutations
- - - - human recessive disorders are found in small populations
    - - survivors could favor certain traits which could alter gene pool
      - as population grows variation decreases
      - Prairie Chicken environment got taken up
        
        small genetic variation
        
        increase in harmful alleles
        
        low egg hatching rates
        
        population decresed
    - - transfer of allele in/out of population due to the movement of fertile individuals
      - could combined populations into a sigle gene pool
      - helps improve ability to survive
- - - - affects the phenotype
      - acts directly on phenotype
      - indirectly geneotype
    - - food can be a factor that favors both ranges
    - - environment changes shift the curve
      - migration can also shift the curve
  - - - Sexual Dimorphism:differences in 2nd sexual characteristics between male and females of the same species
  - - - geneotype not phenotype
      - in sickle cell heterozygote individuals are protected against malaria
- - - - Behavioral Isolation:certain rituals that are common in certain species that attack mates of the same species, enables mate recognition
      - Mechanical Isolation: 2 species mating is attempted but their physical differences prevent them to mate
      - Temporal Isolation: species that breed at different times/seasons/years etc
      - Gametic Isolation:sperm of 1 species may not be able to fertilize the egg of a certain species
        
        sperm cant surevive on reproductive track
        
        the sperm and egg do not match biochemically
      - Habitat Isolation: 2 species that have different habitats in the same area that do not have major barrier just never encounter
    - - Reduced Hybrid Fertility:Hybrids are sterile, meiosis fails to produce normal gametes
        
        1st generation of new species
        
        no gene flow
      - Hybrid Breakdown:some 1st generation hybrid are fertile and mate with either parent species and produce sterile offspring
      - Reduced Hybrid Vulnerability:genes of different species may enable the offspring ability to develop/survive
- - - - sexual selection
      - habitat differentiation
      - polyploidy: comes from an accident during cell division that results in extra sets of chromosomes
        
        autopolyploid:individual with more than 2 chromosome sets that come from a single species
        
        allopolyploid:an infertile offspring is able to produce offspring by making itself fertile asexually
        
        can not interbreed with either parent species= new species
        
        cotton/potatoes/tobacco/wheat
- - - - relocate
      - new hybrid zone forms
        
        improve parent species with environmental conditions
        
        common in insects/birds/plants
        
        allele found in only 1 parent species is transfers to 1st hybrid and then to its offspring
  - - - continued production of hybrid
      - hybrids are continuously reproduced
      - hybrids survive batter than parent generation
      - hybrids are still born even if its selected again ts
        
        hybrid zone extremely narrow
        
        little gene flow reaches the middle
    - - weakling reproductive barriers causes 2 speceis to fuse
      - meet at hybrid zone which weakens the reproductive barrier
      - eventually fuse into 1 species
      - gene pools are similar
      - loss of a species
    - - strengthening reproductive barriers make hybrids
      - hybrid is less fit than parents
      - reinforcement: natural; selection strengthens the prezygotic barriers to the production reducing hybrids
      - stronger for sympatric populations
    - - barriers to gene flow made
      - population diverges from others
      - populations connected by gene flow
      - gene flow reestablished at hybrid zone
- - - - others change gradually
      - punctuated: new species change most when they branched from parent and change little for the rest if their existence
      - gradual: species diverge from 1 species to another slowly and steady over time