Presentation on theme: "Copyright Notice! This PowerPoint slide set is copyrighted by Ross Koning and is thereby preserved for all to use from plantphys.info for as long as that."— Presentation transcript:
1 Copyright Notice!This PowerPoint slide set is copyrighted by Ross Koning and is thereby preserved for all to use from plantphys.info for as long as that website is available. Images lacking photo credits are mine and, as long as you are engaged in non-profit educational missions, you have my permission to use my images and slides in your teaching. However, please notice that some of the images in these slides have an associated URL photo credit to provide you with the location of their original source within internet cyberspace. Those images may have separate copyright protection. If you are seeking permission for use of those images, you need to consult the original sources for such permission; they are NOT mine to give you permission.
2 How did we get from Linnaean Taxonomy… 23568BacteriaArchaeaArchezoansEuglenoidsChrysophytesGreen AlgaeBrown AlgaeRed algaeSlime MoldsTrue FungiBryophytesTracheophytesProtozoansMyxozoansMulticellular Animals
3 To a tree-like concept of organisms? ExtantMulticellular AnimalsMyxozoansProtozoansTracheophytesBryophytesTrue FungiSlime MoldsRed algaeBrown AlgaeGreen AlgaeChrysophytesEuglenoidsArchezoansArchaeaBacteria0.5Land!Animals1Multicellular2First EukaryotesExtinct3Cyanobacterial OxygenLong Time withProkaryotes only4 BYBPOrigin of LifeOriginal Cell
4 Emil Hans (Willi) Hennig German entomologist Hennig developed a mechanism (cladistics) to find the pathways of evolution among related organisms.It is based not only on what one sees, but on many kinds of evidence, including molecular sequences.The pathways are determined by virtue of shared derived characteristics (synapomorphies).Rather than putting organisms into Linnean taxonomic “boxes,” the cladistics process shows the pathway of evolution.Emil Hans (Willi) Hennig German entomologist
5 Evidence Categories History - clearer recently, more obscure anciently Fossils - stratigraphic depth, isotope decay, etc.Chemical - metabolic products such as O2, SsMolecular - DNA sequence alterations, etc.Developmental sequences - onto- phylo- genyBiogeography - Pangea, Gondwana & Laurasia
6 How do we find the Evolution Pathway? Phylogenetic SystematicsInferences from comparison of extant organismsCharacters-Attributes of the organismAnatomyMorphologyDevelopmentPhysiologyMacromolecule SequencesPolarizing Character StatesPlesiomorphies-Ancient, shared by descendantsApomorphies-More-recent derivativesSynapomorphy-Shared among related organismsAutapomorphy-Found only in one organismUse of outgroup to compare to ingroup
7 Typical Cladogram Present Extant A Extant B A’ A” A’” This branching of evolution is called cladogenesis (aka: macroevolution).ExtinctTransitionalFormsA’ is the common ancestor of extant A and extant BTimeThis straight line of evolution is called anagenesis (aka: microevolution).CommonAncestorAncient
8 5 species of frogs found locally What could have made them speciate? https://www.denix.osd.mil/denix/Public/Library/NCR/PhotoGallery/NR-Bull-frog.jpgRana sylvaticaWood FrogRana sphenocephalaLeopard FrogRana catesbeianaBull FrogWhat could have made them speciate?Rana palustrisPickerel FrogRana clamitansGreen Frog
9 Mating Activity Leopard frog Pickerel frog Wood frog Green frog Could the size of the pond, availability of tadpole food, etc. be pivotal?Which frog was mating in mid-March?Which frog was mating in early May?When were three species of frog mating?Why do you think Green and Bull frogs mated so much later?Leopard frogPickerel frogWood frogGreen frogBull frogMating ActivityMarch April May June JulyFigure 1. Hypothetical phenology of frog mating behavior in a pond in the north temperate zone.
11 Model of geographic speciation: interbreeding between populations decreasesKaibab SquirrelNorth Rimone species with unrestricted interbreedingerosionbeginsGrand Canyonprevents interbreedingAbert SquirrelSouth RimTime (10,000 years)
12 Typical Cladogram Present Extant A Extant C Extant B A’ A’ A B constitute a cladeA” C are a grade (is paraphyletic)A”TimeA” C A’ A B are a clade (is monophyletic)A’”A’ A B is the sister group of CCommonAncestorAncient
13 Typical Cladogram Present Extant A Extant C Extant B Extant D Extant E D A””’ E are a ?cladeA””Extinct!Common ancestor +A””’ D E are a ?gradeA”TimeA’”The ABC clade may be, say, a genus.The DE clade may be another genus…in the same familyCommonAncestorAncientThe ABCDE clade would be the family
14 Typical Cladogram Present Extant A Extant B Extant C Extant D Extant E On the otherhand…A””’Extinct!AB are a genusC is a monotypicgenusDE are a genusA”TimeA””A’”ABC might be one familyDE are in another familyCommonAncestorAncientABCDE might constitute an order
15 Protists are polyphyletic (unnatural taxon) Extant Multicellular AnimalsMyxozoansProtozoansTracheophytesBryophytesTrue FungiSlime MoldsRed algaeBrown AlgaeGreen AlgaeChrysophytesEuglenoidsArchezoansArchaeaBacteriaAnimals andFungi are a clade!Plants are a clade (monophyletic)ExtinctEukaryotic organisms are a cladeProkaryotic organisms are a grade (paraphyletic)Living organisms are part of one clade (monophyletic)Original Cell
16 This is the tree-of-life cladogram used by your textbook Fig Pg 601It varies in some minor ways, mostly additions.It shows “uncertainty” as a multifurcation.
17 Bacterial Phyla Extant Extinct Gram negative Gram positive RhodopseudomonadsPurple nonsulfurExtantMycoplasmasActinomycetesProchlorophytesClostridsSpirochetesGreen SulfurCyanobacteriaPurple SulfurDesulfovibriosMyxobacteriaRikettsias+Para-site+Chl B-Cell Wall+ParasiteH2S+µtubuleH2OH2S+Chl A+gliding motilityH2O+NAD+bacteriochlorophyllGram negative+NADPExtinctEach simple line on our tree of life is, in fact, branches with twigs!Each blue hatch mark shows an evolutionary step…mostly biochem!GrampositiveOriginal Cell
18 This is the textbook’s version of the Prokaryotic Cladogram Fig Pg 577It differs mostly by addition of the Archaea.
23 Notice how the marsupials of Australia are a clade (monophyletic). This is an area cladogram in which the cladogram is stretched over geographic domains.Notice how the marsupials of Australia are a clade (monophyletic).It is thought that this represents a single colonization followed by adaptive radiation (rapid speciation).