Mus musculus 85% homology with human DNA Genome of appx. 3 million base pairs
Xenoturburelli No brain, spine, gut or sex organs ~50% homology with humans
Musa acuminata 50% Homology With Humans
Drosophila melanogaster 44% Homology With Humans Shares many similar disorders with humans including insomnia
Saccharomyces cerevisiae 26% Homology With Humans Share the same genes responsible for breast cancer
Escherichia coli 7% Homology With Humans Harmful strains have 1300 genes; harmless have only 530 genes
Phylogeny Def: The Evolutionary History of A Species
Evidence For Evolution Fossil Evidence Homologous Structures –Analogous structures show convergence Embryological Similarities Biochemical Similarities DNA Homology
Cytochrome C Homology cowtuna
Tuna cow
How Did Modern Humans Evolve?
General Primate Characteristics Mammals Large cerebral volume Binocular vision Rotatating forearms & shoulder sockets Opposable digits
Why have primates diverged over the last 65 million years?
Prosimians First group of mammals with primate characteristics Adapted for habitat & niche in trees
Tectonic Shifts 65mya to present
New v. Old World Monkeys Due to continental drift and competition, primates diverge into two smaller factions –Old World (African) –New World (South American) –Despite name, old world monkeys include apes, chimps and orangutans
Miocene Changes & Old World Monkeys Cool weather appx 23.7 mya causes drastic reduction in size of rainforest biome Increased competition among Old World monkeys Those with variations to stand upright are favored for survival on savannah
“Monkeys” v. “Apes”? True monkeys diverge from apes 8 million years ago Apes diverge into two subgroups –Chimp/Gorilla –Southern Apes
Which Model Is Supported? “Lumpers” The chimps, apes and hominoids all diverged at the same time “Splitters” Chimps and apes diverged first Hominoids diverged from chimps later
Lab: Proving Primate Phylogeny via DNA Hybridization of the RH1
Using the RH Factor As Evolutionary Evidence Among primates, there is variance between the DNA sequences in the introns that are part of the Rh1 blood factor By hybridizing DNA from the Rh1 intron with cDNA from a related species, we can determine which species have diverged most recently.
Protocol 1) On your table, you should have five models of DNA and cDNA sequences –Human DNA Template of Rh1 Intron –Human cDNA for Rh1 Intron –Chimpanzee cDNA for Rh1 Intron –Gorilla cDNA for Rh1 Intron –Paranthopus DNA Template for Rh1 Intron 2) In each model the following colors represent various nucleotides –Adenine = Black –Cytosine = Red –Guanine = Yellow –Thymine = Blue
Protocol 3) Make the following comparisons and record how many nucleotides are incorrectly paired (i.e. A-G, C-T, etc.) PairingSequences# of Differences Human Template-Chimp cDNA1 v. 3 Human Template-Gorilla cDNA1 v. 4 Paranthopus Template-Human cDNA5 v. 2 Paranthopus Template-Chimp cDNA5 v. 3 Paranthopus Template-Gorilla cDNA5 v. 4