Introduction to Biogeography PDF

Introduction to Biogeography **BIOGEOGRAPHY** - The study of geographical distribution of organisms in the past and today - Attempts to understand and describe the spatial patterns of diverse living organisms - Attempts to understand and describe the variations of those patterns *...

Introduction to Biogeography **BIOGEOGRAPHY** - The study of geographical distribution of organisms in the past and today - Attempts to understand and describe the spatial patterns of diverse living organisms - Attempts to understand and describe the variations of those patterns **TYPES OF BIOGEOGRAPHY** - Historical Approach. Explain such patterns by focusing on the ancestors of organisms and the changes that happens in the environment - Ecological Approach- focuses on adaptation that are observed in organisms and their interaction to the environment Since Abundance and Distribution of Biodiversity is also highly affected by human activities, biogeography has also become an important role in conservation. **BIOGEOGRAPHY AND ECOLOGY** - **Ernst Haeckel-** German biologist who coined the term ecology - Defined Ecology as total relations of the animal both to its organic and inorganic environment **Ecology** - Study of abundance of organisms in space and time - Processes in biological communities - **In 20^th^ century ecology emerged from natural history and wildlife management** **Biogeography And Ecology** - Ecologist and Biogeographers are **both interested in the patterns of distribution of organisms in space and time** and the **process that determine those patterns, ecology and biogeography** obviously have a close link. - **Ecology** - Interactions between organisms and their environment, patterns and process in ecosystem, as well as with the distribution and abundance. - **Biogeography** - Distribution of organisms and the factors and processes causing those contributions - Studying distribution could be part of a study of abundance - Factors affecting distribution also affects abundance - Theories- sets of ideas that try to explain something - Models- theories that are tested and used to predict the effects of impacts in natural world - **Biogeography, Conservation And Climate Change** - because human population densities are increasing and resources are diminishing, biogeography has a crucial application in sustainability and conservation of biodiversity. - Wildlife conservations are done through just partly by establishing protected areas - **Climate Change** affect the distribution of organisms - Change in biogeography happens due to the **poleward shift** in species distribution that is triggered by climate change - Fishes which are highly affected by changes in temperature - **Environmental Impact Assessment** should be done first before constructing a dam or a flood control system. **Five ways Climate Change Affect Fishes** - Warming of Waters - Decreased water quality - Ocean Acidification - Species Invasions - Droughts **Persistent themes in Biogeography** 1. Classifying geographic regions based on their biotas 2. Reconstructing historical development of their biotas including their origins, spread and diversification 3. Explaining geographic variation in the characteristic of indiv and population **Early Biogeography** 1. **Carolus Linnaeus (1707-1778)** - Binomial nomenclature - Life originated or survived the great flood 2. **Georges-louis Leclerc, Comte de buffon** - Buffon's Law- Environmentally similar but isolated regions have distinct assemblages of mammals and birds 3. **Sir Joseph Banks** - Exceptions in Buffon's Law - Cosmopolitan Species 4. **Johann reinhold Forster** - Phytogeography - Buffon's law is also true for plants - Tendency of plant diversity to decline towards poles 5. **Karl Willdenow** - German Botanist - Multiple site of origination 6. **Alexaner von Humboldt** - Generalized Buffon's Law 7. **Augustin P. de Candolle** - Swiss Botanist - Organisms compete for resources - Contributed to insular floras **Three important advances of the 19^th^ century** 1. **A better estimate to age of earth** 2. **A better understanding of the dynamic nature of continents** 3. **A better understanding of the mechanisms involved in the spread** 8. **Aldolphe Brongniart and Charles Lyell** - Fathers of Paleobotany and geology - Lyell did not belived that species were mutabke and new species and new species did not arrive from earlier species **Four British Scientist** 1. **Charles Darwin** - Origin of Species - HMS beagle 2. **Joseph Dalton Hooker** - Studied plants on southern hemisphere 3. **Philip Lutley Sclater** - Ornithologist - Identified six biogeographic regions 4. **Alfred Russel Wallace** - Father of zoogeography - Wallace line - **Palearctic region** - **Ethiopian** - **Oriental** - **Australian** - **Nearctic** - **Neotropical** **Merriam's Life zones** - C. hart Merriam **Morpho geographic Rules** 1. **Gloger's Rule-** indiv. within humid habitat are darker 2. **Bergmann's-** larger body sizes in cooler climates 3. **Allen's Rule --** Limbs and other extremities are shorter in indiv in colder climates 4. **Cope's Rule-** evolution shows a trend towards increased body size **Four major development in 1950s** 1. **Acceptance of tectonic plates** 2. **Development of new phylogenetic methods** 3. **New ways of conducting research** 4. **Investigations of the mechanisms that limit distribution** **Antonio Snider-Pelligrini** - Introduced the theory of plate tectonic and continental drift **Aldred Wegener** - Reproposed the theory of plate tectonic **Robert H. MacArthur and Edward O. Wilson** - Equilibrium theory on island biogeography - **Cartography-** used in studying, creating and designing maps - **Disciplines:** - Geography - Earth Science - Topology - Politics - **Global Patterns** - A trend experienced or observed throughout the world - **Global winds, ocean and climate** **Remote Sensing** - Science and art of obtaining information about an object, area, phenomenon - Use to assess ground conditions - Allows us to look at changes in environment - **Planning and Transportation** Road Updates Infrastructure monitoring Growth Monitoring - **Natural Resource Mapping** Tree cover Tree conditions Crop conditions Yield estimation Land use change analysis Habitat and natural communities mapping **Reflected E=incident E-absorbed and transmitted E** **PATTERNS OF DISTRIBUTION** a. **Clumped** b. **Random** c. **Uniform** 1. **Cosmopolitan** - Inhabit the whole world, they occur in numerous localities ain all continents 2. **Micro-endemic** - Species that have an extremely restricted distribution that lives only as a single population in a small area **FOUR RLATIVELY COMMON ZONAL CLIMATIC PATTERNS** 1. **Pantropical** - Throughout the tropics 2. **Amphitropical** - Either side of the tropics 3. **Boreal** - Northern part 4. **Temperate** - Middle latitude 1. **Geologic change** 2. **Climatic change** 3. **Evolution** 4. **Jump dispersal** **RELICT GROUP** - Results when shrinking distributions is produced though environmental change and evolutionary process **Climatic Relics** - Survivors of climatic change **Evolutionary relicts** - Living fossils, survivors of an old species **RANGE** **Rapoport's Rule** **-** range size increases as the latitude increases, in other words, generally organisms in nearer the tropics have smaller range size. **RANGE CHANGE** - Species range change due to dispersal and local extinction. **FACTORS LIMITING SPECIES DISTRIBUTIONS** 1. **Abiotic factors** - Physical barriers - Spatial gradients of climatic variables 2. **Habitat, Individual and Population Characteristics** 3. **Species Interaction** - Predation - Competition - Mutualism - Parasitism - The movement of an individual or group from the population they were born in to another location where they settle and reproduce. - **Crowding** - **Food availability** - **Environmental stochasticity** - **Climate change** - **Avoidance of Inbreeding and inbreeding depression** - **Reduce of competition** - **Jump dispersal** - **Diffusion** - **Secular Migration** **AGENTS OF DISPERSAL** - Anemochore - Thalassochore - Hydrochore - Anemohydrochore - Biochore - Zoochore - Anthropochore - Drifting continents - Bats - Insects - Lizards - Rodents - Large mammals **SUPERTRAMPS** - Move ease with water - Reproduce rapidly - Able to colonize and occupy islands - Able to exploit resources effectively **DISPERSAL ROUTES** - **Level 1 Corridors** - **Level 2, Filter Routes** - **Level 3, Sweepstakes Route** **TYPES OF CONNECTIONS FROM AN ISLAND TO AN ISLAND OR TO TOHER CONTINENTS** - Stable land bridges - Periodically interrupted land bridges - Noah's Arks - Stepping-Stone islands - Oceanic islands **LIMITS TO DISPERSAL** - Environmental variables - Temperature - Resources - Physical barriers - Anthropogenic barriers **SPECIATION** **Speciation** - **Process of how new species rise** **MAJOR SPECIES CONCEPT** - **Allopatric speciation** - A once interbreeding population becomes geographically isolated from each other - **Strict allopatry with bottle neck** - **Strict allopatry without population bottleneck** - **Peripatric Speciation** - Happens in population that occurs on the edge of species range - **Parapatric Speciation** - Outcome of divergent evolution in two populations living geographically next to each other - **Sympatric Speciation** - Geographical area and the new species overlap-no spatial separation of the parent population - **Stasipatric Speciation** - Occurs within chromosomal changes **EXTINCTION** - the doom of the vast majority of a particular species - **Local Extinction** - When a species is lost in an area but still present in other patch or places - **Global Extinction** - Loss of species totally **CAUSES OF EXTINCTION** **ABIOTIC FACTORS** - Asteroid Strikes - Loss of habitat - Invasive species - Lack of food - Climate Change - Lack of genetic diversity - Pollution - Better-Adapted Competition - Diseases - Human Predation **BIOTIC FACTORS** - Body size - Niche size - Population size **Specialist Species- most vulnerable as they are specific to their niche** **MACRO VS MICRO EVOLUTION** - **Micro evolution** - Change in gene frequency - **Macro evolution** - Continuous macroevolution for a long period of time will result into macroevolution - CLADE **To reconstruct history, scientist use:** - **Geology** - **Fossils** - **Living organisms** **PATTERNS IN MACROEVOLUTION** 1. **Stasis** 2. **Character Change** 3. **Lineage Splitting** 4. **Extinction** **SPECIES** **Species** - Fundamental concept in biology - Smallest evolutionary independent unit **Essence of speciation is lack of gene flow** **Two stages of speciation:** - **Genetic isolation** - **Differentiation** **SPECIES CONCEPT** - **Biological Species Concept** - a group of interbreeding individuals, that is reproductively isolated from other groups - Only applicable to sexually reproducing organisms - **Phylogenetic Species Concept** - Species is the smallest monophyletic group - **Monophyletic --** one that includes a group of organisms descended from a single organisms - **Polyphyletic-** composed of unrelated organisms descended from one ancestor - **Paraphyletic-** one that includes the most recent ancestor but not all of its descendants - **Morphological Species concept** - Species is a group of phenotypically similar species - Not evolutionary, arbitrary and idiosyncratic - **Ecological Species Concept** - A species is a group of phonetically similar organisms that occupy a given ecological niche - **Allopatric** - **Sympatric** - **Parapatric** - **Chromosomal** **Isolation by:** **Dispersal** **Vicariance** - **Founder hypothesis** - one gravid female disperse to another island and start new isolated population **MECHANISMS OF DIVERGENCE** - **Founder effect speciation** - **Genetic Drift** - **Natural Selection**