DIVERGENCE
Allopatric Speciation
Different Fatherland
Sympatric Speciation
Same Fatherland
ISOLATING MECHANISMS
Geographical Barriers
river
mountains
Biological Barriers
POST-ZYGOTIC MECHANISMS
Hybrid Breakdown
Hybrid Sterility
Hybrid inviability
PRE-ZYGOTIC MECHANISMS
Gametic Isolation
Temporal Isolation
Behavioural Isolation
Habitat Isolation
Mechanical Isolation
Structural
Physical features
Physiological
body processes
Behavioural
Migration
Foraging behaviour
The Fossil Record & Geological Time Scale
Darwin’s Theory
Acanthostega
Archaeopteryx
Biogeography
GEOGRAPHICAL DISTRIBUTION OF SPECIES
organisms evolve in one location
spread out into other regions
Comparative Anatomy & Embryology
Analogous Features
Homologous Structures
Vestigial Structures
Molecular Biology and Genetics
DNA
BIOCHEMISTRY & GENETICS
Scientific Hypothesis
educated guess
Scientific Theory
Why something will happen
Scientific Law
what will happen
Genetic Drift
Changes to allele frequency as a result of chance
The Bottleneck Effect
overhunting
decreased genetic variation in the population.
natural disaster
The Founder Effect
population that has limited input of new genetic material
Nonrandom Mating
leads to a decrease in genetic diversity
NONRANDOM
Inbreeding
Self-fertilization in plants
Assortive Mating
Dog Breeding
Toads selecting mates of similar size
Sexual Selection
Genetic Mutation
new allele
better adaptation
Drives evolution
Seemingly harmful
adaptation to a new or changing environment
Gene Flow
aka Migration
movement of alleles between populations
interbreeding
Natural Selection
Stabilizing Selection
favours the intermediate
Directional Selection
favours the phenotypes at one extreme over the other
Peppered Moths
Disruptive Selection
extremes of a phenotypic range are favoured
formation of new species
Jean-Baptiste Lamarck
The Theory of Inheritance of Acquired Characteristics
The Principle of use or disuse.
perfection
Microscopic organisms arise from non-living sources
1809
The Principle of enquired characteristics
Characteristic enquired over life time are passed
adaption to their environments.
CHARLES DARWIN & ALFRED RUSSEL WALLACE
CHARLES DARWIN
geologist and biologist
Darwin’s Voyage of Discovery(1831-1836)
The Galapagos Islands
The Theory of Natural Selection
1858
ALFRED RUSSEL WALLACE
Father of Biogeography
GEORGES CUVIER
Determined that older the stratum the dissimilar the species are from modern life.
Proposed the idea of catastrophism
Father of peleontology
GREGOR MENDEL
Father of genetics
Studied the Inheritance of traits in peas