The Biogeography of Life Earth and Life Evolve Together Nothing in evolution makes sense except in the light of molecular systematics Yes in part But it is a two way interaction Ecology Ecology Genetics Biogeography Phylogeny Morphology Development Future of Molecular Systematics 1 Biogeography 2 Ecology 3 Genomics Genomics Phylogeny Morphology Development Cytology Genetics Morphology Phylogeny Development Taxonomy Cytology Future of Molecular Systematics 1 Biogeography Ecology Biogeography Taxonomy Biogeography 2 Ecology 3 Genomics Taxonomy Cytology Science Magazine 13 Oct 2006 1 Future of Molecular Systematics Future of Molecular Systematics 1 Biogeography 1 Biogeography 2 Ecology 2 Ecology 3 Genomics Ecology Biogeography 3 Genomics Svante Paabo MaxPlanck Institute Genomics Phylogeny Morphology Development Taxonomy Cytology Draft Neandertal Genome Science Magazine 7 May 2010 The Biogeography of Life The Biogeography of Life that grand subject that almost keystone of the laws of creation Geographical Distribution that grand subject that almost keystone of the laws of creation Geographical Distribution Charles Darwin 1845 in a letter to Joseph Dalton Hooker later Director of the Royal Botanic Garden Kew Darwin needed two chapters in the Origin of Species to cover his ideas on geographical distributions of organisms I am prepared to go to the stake if requisite in support of the chapters on the geological and geographical distribution of life Thomas Huxley after reading the Origin of Species 2 The Biogeography of Life What is Biogeography Alexander von Humboldt 1769 1859 First naturalist to make explicit distinction of vegetation and flora and connection between climate and plant distributions 1 How are organisms and their attributes distributed over the surface of the earth and over the history of the earth 2 Why do organisms and their attributes show these patterns of distribution Argyroxiphium sandwicense Haleakala silversword Approaches to Biogeography Approaches to Biogeography Biogeography is a broad field requires information from Biogeography is a broad field requires information from ecology systematics evolutionary biology population biology genetics cytology morphology and anatomy physiology paleobiology the geosciences and natural history ecology systematics evolutionary biology population biology genetics cytology morphology and anatomy physiology paleobiology the geosciences and natural history 3 main flavors of biogeography Argyroxiphium sandwicense Haleakala silversword Argyroxiphium sandwicense Haleakala silversword 3 Floristic or Faunistic Biogeography Floristic or Faunistic Biogeography Where various taxa are distributed Where various taxa are distributed Where are members of the Cactaceae cactus family found Where are members of the Bromeliaceae pineapple family found Provides the backbone of data for historical biogeography Ecological Biogeography Distributions of attributes of organisms without concern to their classification Koompassia Fabaceae Ecological Biogeography Distributions of attributes of organisms without concern to their classification Why do rainforests occur where they do Why do deserts occur where they do The plants that dominate the rain forests of southeast Asia are taxonomically distinct from those of South America but forests are physiognomically similar e g giant buttress rooted emergent trees The plants that dominate the deserts of North America are taxonomically distinct from those of Africa but succulent plants are physiognomically similar Vegetation looks the same but the floras are different Humboldt Vegetation looks the same but the floras are different 4 Ecological Biogeography Ecological Biogeography Vegetation vs Flora provides numerous examples of unrelated organisms showing convergent analogous features as responses to similar environmental pressures Vegetation vs Flora provides numerous examples of related organisms in one area showing divergent homologous features as responses to different environmental pressures Similar body shapes and structures have evolved in the North South American desert cacti and separately in the euphorbias in southern African deserts Related cacti have diverged tremendously in shape and habit in response to desert subtropical forest and tropical forest epiphytic conditions in the New World Historical Biogeography Historical Biogeography Combines organismal history with geological events to explain past and present distributions Combines organismal history with geological events to explain past and present distributions Requires information from previous two branches of biogeography plus phylogenetics and earth history The interplay of geological and biological evolution is critical in understanding why the Haleakala silversword is found in Maui when and where it or its ancestors came from and why it is has specific features of morphology chromosome number and physiology 5 Biogeography includes island biogeography Biogeography includes dispersal biogeography Biogeography includes paleobiogeography Biogeography includes glacial history Jurassic Period 208 146 mya The final shaping of North American and Great Lakes flora and vegetation occurs during the Recent Epoch Holocene following the glaciation of the Pleistocene Modern genera are first seen for Ginkgo Pleistocene Holocene 6 Biogeography includes plate tectonics Biogeography includes plate tectonics Alfred Wegener 1920 described both plant and animal fossil examples supporting his theory he believed that this biogeographic data was the strongest evidence for his theory geological strata continuous between continents fossil disjunct distributions between continents Glossopteris Permian fern Cretaceous Present Mesosaurus Permian freshwater reptile Cynognathus Triassic land reptile Lystrosaurus Triassic land reptile Biogeography Phylogenetics If philosophy is the devil s whore as Martin Luther once quipped then biogeography and biological systematics are fast becoming Old Nick s bordello Craw 1988b Phylogenetics and historical biogeography are now intimately intertwined Disjunctions how are these distribution patterns explained Two main ideas geological events separate once continuous biota vicariance dispersal events over geological barriers dispersalism 7 Disjunctions how are these distribution patterns explained Disjunctions how are these distribution patterns explained Dispersalist paradigm Vicariance paradigm fragmentation of once continuous