Ecology - Some Basic Ideas PDF

Ecology - some basic ideas BIOL2050 Ecology Instructor: Dr. Birgit Schwarz [email protected] NOT FOR SALE OR DI...

Ecology - some basic ideas BIOL2050 Ecology Instructor: Dr. Birgit Schwarz [email protected] NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY Extinction Fossil record shows that 99% of all species that ever lived are extinct The rate of extinction varies background (normal) vs mass extinction – when a large proportion of the earth’s species are wiped out in a short span of time NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY  65 million years ago: The last mass extinction NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY  Most recent fossils at top of rock profile Older fossils at bottom Niagara Gorge NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY  65 mya: no more large reptiles 66 million yrs ago: fossils of dinosaurs, pteranodons, plesiosaurs, etc. Credit: Kirk Johnson, Denver Museum of Nature & https://www.astrobio.net/meteoritescomets-and- Science asteroids/it-had-to-be-an-asteroid/ NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY  Today: the Biodiversity Crisis No. of years that it normally would have taken for the observed vertebrate species extinctions in the last 114 years to occur under a background rate Gerardo Ceballos et al. Sci Adv 2015;1:e1400253 Copyright © 2015, The Authors → Current bird & mammal extinction rate 100-1000X higher than background rate → Comparable to the dinosaur extinction NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY  Interconnectivity & complex relationships NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY  Definition: Ecology is… …the scientific study of interactions between organisms and their environment*. More detailed: …the scientific study of the distribution and abundance of organisms, and the interactions that determine distribution and abundance. In other words: Where organisms are found, how many occur there & why living (biotic) * environment & non- living (abiotic) NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY  Events in nature are interconnected Organisms interact with one another & their physical environment. → A change in one part of an ecological system can alter other parts of that system. “You can never do just one thing” NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY A nested hierarchy: Ecology operates and is studied at many levels NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY Copyright © 2014 Pearson Canada, Inc.  Individual A nested hierarchy: Ecology operates at many levels NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY Copyright © 2014 Pearson Canada, Inc.  Individual A nested hierarchy: Population Ecology operates at many levels Population = group of individuals of the same species within a particular area NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY Copyright © 2014 Pearson Canada, Inc.  Individual A nested hierarchy: Population Ecology operates at many levels Community Community=group of (interacting) populations of different species within an area NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY Copyright © 2014 Pearson Canada, Inc.  Individual A nested hierarchy: Population Ecology operates at many levels Community Ecosystem= community & its abiotic environment Ecosystem NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY Copyright © 2014 Pearson Canada, Inc.  Individual A nested hierarchy: Population Ecology operates at many levels Community Landscape=broader area, (usually) Ecosystem composed of different ecosystems Landscape NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY Copyright © 2014 Pearson Canada, Inc.  Individual A nested hierarchy: Population Ecology operates at many levels Community Biosphere=All living organisms on earth, plus their environments Ecosystem Landscape Biosphere NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY Copyright © 2014 Pearson Canada, Inc. A nested Individual Behavioural hierarchy: Ecology, Ecology operates Physiological Population Ecology & is studied at Population Ecology many levels Community Ecosystem Landscape Biosphere NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY Copyright © 2014 Pearson Canada, Inc. A nested Individual Behavioural hierarchy: Ecology, Ecology operates Physiological Population Ecology & is studied at Population Ecology many levels Community Community Ecology Ecosystem Ecosystem Ecology Landscape Landscape Ecology Relatively recent area (e.g. use of satellite data to map & study Biosphere ecosystems) NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY Copyright © 2014 Pearson Canada, Inc. Other new areas in Ecology Conservation Ecology/Biology Interdisciplinary Goal: maintenance of biological diversity Restoration Ecology: “repairing” disturbed communities Global Ecology: earth as a single ecosystem Urban Ecology: interaction of living organisms with each other and their surroundings in the context of an urban environment NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY  Ecology vs. Environmental Science Ecology refers to a scientific endeavor, not environmental activism. Environmental science Book photo created by jcomp - www.freepik.com incorporates concepts from the natural sciences (including ecology) and the social sciences and focuses on how people affect the environment and how to address environmental problems. created by rawpixel.com - www.freepik.com NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY  Image Credit: NASA's Earth Observatory “The human brain now holds the key to our future. We have to recall the image of the planet from outer space: a single entity in which air, water, and continents are interconnected. That is our home.” -David Suzuki NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY  Course Content (subject to modification) We will consider: community structure and the link between ecology dynamics and evolution factors that influence species approaches to the study of richness and biodiversity ecology and experimental design energy flux and nutrient cycling in ecosystems biomes and climate sustainability adaptations of animals and plants the biodiversity crisis properties of populations and the impact of climate change on biodiversity population growth competition, predation and mutualism NOT FOR SALE OR DISTRIBUTION PROPERTY OF YORK UNIVERSITY