BIOL 1543 1st Edition Outline of Last Lecture I COMMUNITY ECOLOGY Lecture 20 II PREDATION III PREDATION MIMICRY IV PREDATION COMMUNITY DIVERSITY V HERBIVORY VI TROPHIC STRUCTURE VII ECOSYSTEM ECOLOGY VIII CHEMICAL CYCLING CARBON AND WATER Outline of Current Lecture I THE BIODIVERSITY CRISIS OVERVIEW II CURRENT THREATS to biodiversity III PHOTOSYNTHESIS SOLAR RADIATION AND EARTH S ATMOSPHERE IV Global warming could alter the biosphere V Greatest FUTURE threat to biodiversity VI What about the ozone layer VII What can we do VIII What can YOU do IX What SHOULD we do X One planet one experiment E O Wilson Current Lecture I THE BIODIVERSITY CRISIS OVERVIEW We are now presiding over a biodiversity crisis a rapid decrease in Earth s great variety of organism Conservation biology is a goal driven science that seeks to counter A B the biodiversity crisis C There are over 1 5 million species known to science and between 10 200 million total D What is happening and why should we care E Biodiversity includes 1 Genetic diversity within and between populations 2 Species diversity iii Ecosystem diversity A Biodiversity while valuable for its own sake also provides food fiber medicines and ecosystem services B Human activities threaten diversity at all levels II CURRENT THREATS to biodiversity a Habitat destruction introduced species and overexploitation are the major threats to biodiversity b Three primary threats i Habitat destruction is the single greatest current threat to biodiversity ii Introduced species AKA naturalized species AKA exotic species can disrupt communities by competing with or preying on native species 1 an organism not normally occurring in an area that has been accidentally or intentionally introduced to the are iii Overexploitation of wildlife by harvesting has threatened various animal and plant species world wide consumption III PHOTOSYNTHESIS SOLAR RADIATION AND EARTH S ATMOSPHERE a Photosynthesis moderates global warming i Greenhouses used to grow plants trap solar radiation raising the temperature inside b Excess CO2 in the atmosphere is contributing to global warming Photosynthesis which removes CO2 from the atmosphere moderates this warming a The burning of fossil fuels is increasing the amount of CO 2 and other greenhouse gases in the air b The increase of these gases in the atmosphere leads to global warming i solve the problem by either producing less CO2 or increase photosynthesis V Greatest FUTURE threat to biodiversity a Global warming may change climate patterns melt polar ice caps flood coastal regions b More importantly it may increase the rate of species loss VI What about the ozone layer a Solar radiation converts O2 high in the atmosphere to ozone O3 which shields organisms on the Earth s surface from the damaging UV radiation b Industrial chemicals called CFCs chlorofluorocarbons have caused dangerous thinning of the ozone layer but international restrictions on CFC use are allowing recovery i Excessive UV exposure leads to increased incidence of genetic mutation and thus cancer VII What can we do a Protected areas can be established to slow the loss of biodiversity i Biodiversity hot spots areas around the globe that must have at least 15 hundred vascular plant species as endemics and have lost 70 of the original habitiat have large concentrations of endemic species They provide an opportunity to protect many species in very limited areas purple areas b Migratory species both terrestrial and aquatic may require international protection c Sustainable development is an ultimate goal i Sustainable development seeks to improve the human condition while conserving biodiversity development that meets the needs of the present without compromising the ability of future generations to meet their needs ii It depends on increasing and applying ecological knowledge as well as valuing our linkages to the biosphere iii Resources 1 http www wwf org 2 http www nature org 3 http www airnow gov VIII What can YOU do a Be educated b Be active c Conserve energy and water d Contact your representatives e Recycle f Walk bike carpool bus more often g THERE IS HOPE FOR THE FUTURE IX What SHOULD we do a Cloning and other genetic work raises new possibilities for conservation biology b Should we bring them back c New ecosystems new interactions d Lessons from science fiction X One planet one experiment E O Wilson Don t goof it up