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EVIDENCE OF EVOLUTION. I. FOSSILS USUALLY FOUND IN SEDIMENTARY ROCK LAYERS. “OLD AT THE BOTTOM & NEW AT THE TOP!”. II. EVIDENCE IN LIVING ORGANISMS. A. DNA, RNA, & ATP ARE SIMILAR BETWEEN ALL SPECIES. B. HOMOLOGOUS STRUCTURES:.
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EVIDENCE OF EVOLUTION I.FOSSILS USUALLY FOUND IN SEDIMENTARY ROCK LAYERS. “OLD AT THE BOTTOM & NEW AT THE TOP!”
II. EVIDENCE IN LIVING ORGANISMS • A. DNA, RNA, & ATP ARE SIMILAR BETWEEN ALL SPECIES.
B. HOMOLOGOUS STRUCTURES: • BODY STRUCTURES THAT ARE SIMILAR IN FUNCTION AND EARLY DEVELOPMENT.
EX. FORELIMBS OF THE BAT, PENGUIN, ALLIGATOR, & HUMAN. • STRUCTURES LOOK DIFFERENT, YET COME FROM THE SAME STRUCTURES OF THE EMBRYO.
D. VESTIGIAL ORGANS: • STRUCTURES/ORGANS THAT SERVE NO USEFUL FUNCTION. • EX. TAILBONE, APPENDIX, EAR MUSCLES, BODY HAIR, NICTITATING MEMBRANE.
III. DARWIN’S SAYS… • LIVING ORGANISMS EVOLVED THROUGH GRADUAL CHANGES OF EARLIER FORMS. • THIS IS “DECENT FROM A COMMON ANCESTOR”.
DARWIN’S POINTS ARE THE MAIN BASIS OF EVOLUTIONARY THOUGHT TODAY.
IV. PATTERNS OF EVOL.TYPE 1. - COEVOLUTION • A CHANGE IN ONE, TRIGGERS A CHANGE IN ANOTHER. • EX. FLOWERING PLANTS AND THE INSECTS THAT POLLINATE THEM.
TYPE 2. - CONVERGENT EVOL. • UNRELATED SPECIES APPEAR SIMILAR. • BASED ON LIVING IN SIMILAIR ENVIRONMENTS. • EX. DOLPHINS, SHARKS, & PENGUINS
ANALOGOUS STRUCTURES- • STRUCTURES SIMILAR IN APPEARANCE & BEHAVIOR, YET ARE FROM DIFFERENT CELL ORIGINS • EX. BUTTERFLY WINGS & BAT WINGS
TYPE 3 - DIVERGENT EVOL. • RELATED SPECIES BECOME LESS ALIKE. • DUE TO MIGRATING TO DIFFERENT ENVIRONMENTS • EX. RED FOX (FORESTS) AND KIT FOX (DESERTS) • BROWN BEARS & POLAR BEARS
A. STABILIZING SELECTION • SELECTION OF THE AVERAGE FORM OF A TRAIT. • NOT THE EXTREME • EX. INFANT BIRTH WEIGHT
B. DIRECTIONAL SELECTION • SELECTION OF ONE OF THE EXTREME VARIATIONS OF A TRAIT. • EX. BEAK SHAPE ON THE GALAPAGOS • EX. ANTIBIOTICS
C. DISRUPTIVE SELECTION • SELECTION OF BOTH EXTREMES OF A VARIATION. • EX. BEAK SIZE AND AVAILABLE SEED SIZE • “BIG BEAK & BIG SEEDS” • “LITTLE BEAK & LITTLE SEEDS”
D. SEXUAL SELECTION • CHOICE OF A MATE BASED ON THE PRESENCE/ ABSENCE OF CERTAIN TRAIT/S. • EX. CHARLES MANSON, MICHAEL JACKSON
**ARTIFICIAL SELECTION • EX. SELECTIVE BREEDING • HUMANS SELECT CERTAIN TRAITS FOR A DESIRED OUTCOME. • EX. DOGS, FRUITS & VEGGIES
VI. SPECIATION - FORMING OF A NEW SPECIES THROUGH THE PROCESS OF EVOLUTION.