BIOL 1200 2025 8 Evol History, EvidenceStdnts
Page 1: Introduction to Evolution
Title: EVOLUTION
Subtitle: Only here, it seems.
Theme: The puzzle of biodiversity
Page 2: Public Perception of Evolution
Evolution tends to face skepticism, with some views considered outrageous.
Emphasis on evidence in science rather than belief.
Importance of evolution in understanding life.
Page 3: The Significance of Evolution
Quote from Theodosius Dobzansky: "Nothing makes sense in biology except in the light of evolution."
Page 4: Definitions of Evolution
Evolution defined as:
Descent with modification
Changes in allele frequencies across generations.
Fundamental property of populations and species.
Page 5: Historical Context
Charles Darwin:
Born in 1809 to a wealthy British family.
Briefly studied medicine at Edinburgh.
Attended Cambridge for ministry studies.
Developed an interest in beetle collection.
Served as the ship's naturalist on HMS Beagle starting in 1831, which established his scientific reputation.
Page 6: Darwin in 1840
Reference to Darwin's status in 1840 as depicted in Price 1996's publication.
Page 7: Darwin's Observations and Insights
After returning from the voyage, Darwin was unwell but wealthy.
Noticed geographic variations and organism similarities within regions.
Struggled to comprehend adaptation until reading Malthus in 1838, which inspired the natural selection concept.
Wrote a secret essay in 1844 detailing his thoughts.
Page 8: Alfred Russel Wallace
Recognized as a prominent figure parallel to Darwin in discussing natural selection.
Wallace worked in regions such as Indonesia and Malaysia.
Page 9: The Presentation of Natural Selection
In June 1858, Wallace shared his manuscript outlining natural selection with Darwin.
Both presented their findings to a major scientific society in London.
In 1859, Darwin published "Origin of Species":
Documented evidence for evolution.
Explained natural selection as the primary mechanism for adaptation.
Page 10: Acceptance of Evolution
Evolution quickly gained acceptance among scientists.
Natural selection faced skepticism until Mendel's genetics were integrated into evolutionary theory.
Page 11: Evidence of Evolution vs. Special Creation
Evidence for evolution in contrast to the belief of "special creation" (supernatural origins).
Homologous similarities:
Traits shared among organisms due to common ancestry, inherited through descent.
Different from convergent functional similarities.
Page 12: Examples of Homologous Structures
Similar limb structures in tetrapod vertebrates (e.g., humerus, radius, ulna) exist despite different functions.
Molecular characteristics also show sets of homologies.
Page 13: Vestigial Organs
Vestigial organs are features that have reduced function but are shared with ancestors.
Examples include the pelvic girdles in snakes and whales.
Also noted are molecular vestiges.
Page 14: Fossil Evidence of Evolution
Transitional fossils demonstrate the hind limb loss in ancient marine mammals:
Indohyus, Pakicetus, Ambulocetus, Basilosaurus, Bowhead whale.
Key structures include tibia, femur, pelvis.
Page 15: Biogeographic Patterns
Importance emphasized by Darwin and Wallace:
Related species often found in close geographical proximity, such as Galapagos birds.
Strata fossils show progression and similarity with adjacent layers, supporting descent with modification.
Page 16: Niche Adaptations
Observance of niche similarities in placental mammals versus Australian marsupials (e.g., different burrowers and climbers).
Highlight of convergent evolution reflected in ecosystem adaptations.
Page 17: Direct Observations of Evolution
Real-time observations of evolution:
Examples include Peppered moths, Darwin’s finches, and sticklebacks.
Phenotype variations observed in Gasterosteus aculeatus, changes correlating with environmental factors noted.
Page 18: Evolution in Action
Rapid evolution of armor in specific populations of sticklebacks observed over time.
Frequency data showing the shift in morph types during the observation period.
Page 19: Resistance Develops in Nature
Increases in antibiotic resistance correlated with the frequency of antibiotic use in Finland.
Highlighted by the rise in infections among middle ear bacteria with increased beta-lactam usage.
Page 20: Experimental Evolution
Artificial selection examples presented by Darwin:
Breeders influencing traits in dogs, cabbages, and pigeons.
Insights into speciation observed experimentally in controlled conditions.