aBio Evolution

• 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

• 1798 Essay
• Charles lyell 1830 geology (earth is old)

• Essay of 1842
• Not published

• Got a letter from naturalist Alfred Russell Wallace
• July 1st 1858 - joint papers given by wallace and by darwin

• 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

Physical characteristics

Group of organism, interbreeding, in 1 area, in 1 species

at the genes in a population

• biotic factors - Living
• abiotic factors - non living

mutation

• 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

• 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

• "microevolution"
• Natural Selection is a process and results in microevolution

• 1. Stabilizing N.S.
• Example: human birth weight
• Those on ends of curve are at a disadvantage

• 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

• Any function or structure that produces better adjustment of organism to environment.
• Natural selection (process)---> adaptation

• Change in allele frequencies through time
• (NS) process ----> microevolution

2 or more species interacting, and they are selective force on other. (deer and wolves)

• 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