aBio Evolution

  1. Charles Darwin
    • 1809-1882 British
    • 1831- Done w theology school
    • Naturalist on HMS Beagle 1831-1836 (5 years)
    • Galapagos islands (off pacific s america) 6 weeks
    • -Saw: toroises, mocking birds, finches, cacti, etc...
    • Came home- thought/writing/reading/communication
  2. Thomas malthus
    • 1798 Essay
    • Charles lyell 1830 geology (earth is old)
  3. 1842
    • Essay of 1842
    • Not published
  4. 1858
    • Got a letter from naturalist Alfred Russell Wallace
    • July 1st 1858 - joint papers given by wallace and by darwin
  5. 1859
    • Published "origin of species"
    • Ideas- world is not static, it is changing
    • Change could be spoken as "evolving"
    • Evolution is "Gradual"
    • Natural selection is a process / results in evolution
  6. Phenotype / Genotype:
    Physical characteristics
  7. Population:
    Group of organism, interbreeding, in 1 area, in 1 species
  8. Gene pool
    at the genes in a population
  9. Environment:
    • biotic factors - Living
    • abiotic factors - non living
  10. variation:
    mutation
  11. Natural Selection -
    • Differential perpetuation (survivial/reprodcution) of genotypes
    • (some genotypes do better than others)
    • 1. organisms can reproduce sexually
    • 2. there is inheritable variation
    • 3. testing of organisms by environment
  12. EXAMPLE OF NATURAL SELECTION:
    • Gophers: digging abilities
    • F: faster
    • f: slow
    • FF Ff ff
    • Foxes eat ff --> FF Ff
    • Example of natural selection - some genotypes have done better than others.

    • Allele freq: Before: F 3/6 f 3/6
    • After: F 3/4 f 1/4
  13. Change in allele frequencies:
    • "microevolution"
    • Natural Selection is a process and results in microevolution
  14. Types of NS: stabilizing NS
    • 1. Stabilizing N.S.
    • Example: human birth weight
    • Those on ends of curve are at a disadvantage
  15. Directional NS
    • individuals at one end of the curve are at an advantage at other end they are at a disadvantage.
    • Ex: squirrels w longer fur survive through winter
    • Ex: increased resistance to antibiotics in bacteria
    • Ex: Plants around mine tailings
    • Ex: moth coloration: Melanistic moths *industrial melanism)
    • Pre 1850- moths were light, mostly
    • Post 1850- many moths are dark
  16. Disruptive NS:
  17. Adaptation:
    • Any function or structure that produces better adjustment of organism to environment.
    • Natural selection (process)---> adaptation
  18. Microevolution:
    • Change in allele frequencies through time
    • (NS) process ----> microevolution
  19. CoEvolution:
    2 or more species interacting, and they are selective force on other. (deer and wolves)
  20. Variabiltiy 0
    • IT EXISTS-
    • 1. origin - mutation
    • 2. How is it observed / quantified?
    • a) morphological variation (ex flower color)
    • b) enzyme variabilty -
    • allozymes- alternate forms of an enzyme
    • -coded for by same locus
    • -gel electrophoresis may tell them apart
    • H: heterozygosity - % loci heterozygous in an individual (humans 7%)
    • P: polymorphism - % loci polymorphic in an population (humans 38%)

    • c) variation in DNA - more vairabilty in dna than in enzymes.
    • aa - diff codons --- variability

    • d) eq of variabilty - hemoglobin molecule (sickle cell anmenia)
    • Higher in africa - carrier for sickle cell - immune to malaria
  21. Arguments for variability:
Author
Anonymous
ID
147585
Card Set
aBio Evolution
Description
EVOLUTION
Updated