Presentation on theme: "Evidence for Evolution"— Presentation transcript:
1 Evidence for Evolution Direct Instructionthen synthesis on 24R
2 EVOLUTION = Change over Time =Descent With Modification =Adaptation of a species Takes Place Over Long Periods of Time-usually millions of years
3 Descent With Modification Species Today Look Different From Their AncestorsEach Living Species Has-Descended-With Changes-From Other Species-Over Time
4 Descent With Modification ImpliesAll Living Organisms Are RelatedSingle Tree of LifeDNA, Body Structures, Energy SourcesCommon DescentAll Species, Living (Extanct) & Extinct, Were Derived From Common Ancestors
9 Evidence of Evolution— 2. Comparative Anatomy Anatomy has different functions but constructed of similar bones in similar way.Evo predicts that modifications of ancestral body parts are more likely than formation of entirely new parts2 Kinds:Homologous Structures: same structures/different functionsAnalogous Structures: different structures/same functionsan analogy= a comparison using like or as (this snake tastes like chicken, but is it?)
10 Homologous Structures Structures in different organism that indicate a shared ancestryCheck out these vertebrate forelimbs.
18 Comparative Embryology Shows common ancestry Video:ibrary/04/2/l_042_02.html
19 Evidence of Evolution— 4. Comparative Biochemistry Proteins (Amino Acid)MORE differences in AA sequences of distant related speciesLESS differences = species that are more closely related.Nucleic AcidsMORE differences in DNA sequences of distant related species
20 Similar DNA = Similar AA = Similar Organisms Which is more related to the human,the snake or the tuna?Similar DNA = Similar AA = Similar Organisms
21 Evidence of Evolution— 5. Comparative Biogeography Different Species On Different Continents Have Similar Adaptations due to similarities of the Environments
22 Organisms from different land masses look similar The most recent common ancestor is those of the same geographical region.But, the similar comparative anatomy demonstrates a distant common ancestor before the land masses separated.
23 Elephants Asian African Ex of a species with a common ancestor that became geographically isolated over 5.5 MYA from others in their species and then continued to evolve.And the evolution was convergent –Becoming the African and Asian Elephants we know today.
24 Evidence of EvolutionFossil RecordComparative AnatomyComparative EmbryologyComparative BiochemistryComparative Biogeography