A hypothetical trace of evolution One original common ancestor Scientists use both morphology and genetics to produce phylogenic trees Morphology share similar physical characteristics Analysis of genetic similarity ID: 688624
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Slide1
Homologous and Analogous StructuresSlide2
A hypothetical trace of evolutionOne original common ancestor
Scientists use both morphology and genetics to produce phylogenic trees
Morphology- share similar physical characteristicsAnalysis of genetic similarity
Phylogenic treesSlide3
They can get very specific and complicated….Slide4
the study of the body structures in different organismsanatomical similarities gives evidence of a common ancestor
Comparative Anatomy
Human
Dog
SealSlide5
Structures that are similar but has different functions
Shows common
ancestry
Homologous structuresSlide6
Acquiring the same biological trait independentlyExample: Flight
Humming bird and moth - last common ancestor did not have wings
They acquired these traits separately Only very few designs for a wing would allow for hovering
Convergent EvolutionSlide7
Similar functions but differ
in
structureEx: wings of a hummingbird and humming moth – both can hover to feed
Analogous StructuresSlide8Slide9
Divergent Evolution
Two or more related populations or species become more and more dissimilar.
Divergence is nearly always a response to differing habitats and can result in new speciesSlide10
Adaption Radiation
Many related species evolve from a single ancestral species ex: Galapagos finchesSlide11
Features that were useful to an ancestor, but they are not useful to the modern organism that has
th
.
tailbone in humans Appendix
Some snakes
have tiny pelvic bones and limb
bones
Vestigial StructuresSlide12
Vestigial StructuresSlide13
Closely related organisms often have similar stages in their embryonic development
All
vertebrate embryos are similar
Vertebrates share a common ancestor
Comparative Embryology-
Karl von Baer
lemur
pig
humanSlide14
Vertebrate EmbryosSlide15
All organisms share related biochemical processes:All cells use DNA as genetic blueprint
All use RNA,
ribosomes, and approximately the same genetic code for translationAll use roughly the same set of 20 amino acids to build proteins
All use ATP to transfer energy
Similarities at the Molecular LevelSlide16
the DNA nucleotide sequence of the human and mouse cytochrome
c gene is very similar, suggesting shared ancestry
Striking genetic similarities between organisms imply evolutionary relatednessSlide17
1 2 3 4 5 6 7 8
Where do you think these would go on a phylogenic tree? What do you think they are?Slide18
6 3 8 1 4 5 7 2Slide19Slide20