Week 5 Ecology September 16 2013 Ecology Population Community Carrying Capacity naturally sustain Limiting factors the study of how organisms interact with each other and their environment individuals of a single species living in a given space and time birth and immigration moving into population death and emigration exiting a population o Increase by o Decrease by o Per Capita each head the presence of all populations living in a given space and time maximum number of individuals that an environment can any factor that limits or caps the population o Food water space or predators etc HUMAN POPULATION Last 180 years 6 billion humans o How many humans are added to the population each day 250 000 Species Interactions harm the other o 1 Commensalism interaction that directly benefits one species but does not Nesting birds barnacles on whales Remoras fish lives on sharks o 2 Mutualism interaction that benefits both species Cleaner fish clean other fishes mouths ants and plants termites and the organisms in their body o 3 Interspecific Competition competition for the same resource neither species benefits both species involved are placed at a disadvantage Seed eating birds mollusks o 4 Predation one species organism uses another species organism as food but does not reside directly in or upon the organism it s using Lions tigers bears o 5 Parasitism one species organism uses the other species organism as a nutrient source and resides directly in or upon the organism it is utilizing Ticks leeches bacteria Brood Parasite brown headed cowbird September 18 2013 Pediculosis head lice are human parasites o Feed on human blood Bed Bugs blood feeding parasites Trophic Stuff o 1 Carnivore feed on meat o 2 Herbivore feed on plants o 3 Omnivore feed on both o 4 Scavenger feed on dead o 5 Saprovore feed on decaying materials o 6 Frugivore feed on fruits Life Expectancy o Length of time an individual is projected to survive in a specific population o Humans in the U S have a life expectancy of 78 years o What is the longest life expectancy on earth and where o What is the shortest life expectancy on earth and where 84 Macau China 38 Angola Africa o Life expectancy of Zebra Mussels 2 3 years Survivorship Curves plotting population vs how long an individual is expected to live in the population o Type 1 Typically large mammals organisms ex Humans Have only a few offspring per reproductive event Provide large amount of parental care Small mammals organisms ex Birds Have many offspring per reproductive event Provide some amount of parental care o Type 2 o Type 3 Small organisms invertebrates Have many millions of offspring per reproductive event Provide minimal to no parental care Exotic Species o Worst Case Scenario o Exotic Species NO natural predators CAN out compete natives o Native Species HAVE natural predators Can NOT out compete exotics o Natives may become rare extirpated no longer occurs where it used to or extinct o About 4 500 species established in the U S o EXOTIC SPECIES o Any species that does not naturally occur in a particular region Introduced by artificial means Also called non indigenous species o NATIVE SPECIES o A species that occurs naturally in a particular region Also called indigenous species Sea Lamprey exotic species o Round mouth filled with sharp teeth o Adapted to lake life and now sticks to fish and kills them Corbicula exotic species o Asiatic Clam from Asia Zebra Quagga Mussels exotic species o Mid 1980 s introduced into Ohio Michigan o Grow on top of native mollusks Goby Fish exotic species o Raised eyes and single fins make these fish different Aedes Japonicas exotic species o Mosquito that carries West Nile and can bite during the day September 20 2013 Emerald Ash Borer exotic species o Dig holes in tree and start to dehydrate and starve the tree Endangered Species o Also called listed species o A species that may become extinct in the near future Threatened Species Special Category o A species that may become an endangered species in the foreseeable future o Any species that may need to be listed as endangered or threatened in the future Regulated by US Fish and Wildlife Service o Power of listing and power of delisting In Ohio o Mollusks 30 species endangered o Fish 25 species endangered o Birds 25 species endangered Most endangered in North America is the Native Bivalves Unionids o North American has about 300 species 55 are endangered or already extinct o Most endangered group of species DNA o Deoxyribonucleic Acid o DNA is the major component of our chromosomes o DNA is found in a double strand double helix configuration o Most of your DNA is found in the nucleus of your cells