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Summer 2010 Workshop in Biology and Multimedia for High School Teachers “Finds tongues in trees, books in the running brooks, sermons in stone, and good in every thing.” William Shakespeare http://upload.wikimedia.org/wikipedia/commons/4/40/Large_leaved_linden.png David Eatough Revere High School Understanding Biodiversity “We need an expedition to planet Earth, where probably fewer than 10 percent of the life forms are known to science, and fewer than 1 percent of those have been studied beyond a simple anatomical description…” E. O. Wilson 2006 “The Creation” Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College How much do we truly know about life on earth? Objectives: • To better understand what humanity knows about life on earth • To understand the value of biodiversity to earth and ourselves • To better understand the methods used by science to explore and measure biodiversity • To understand how humanity has altered biodiversity Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College What is biodiversity? Biodiversity is: • the variety or richness of life at all structural levels (molecular/genetic, species, ecosystem). • an essential renewable resource. • exploited and depleted by human activities The current rate of biodiversity loss is comparable to previous extinction events. Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College http://en.wikipedia.org/wiki/File:Undiscovered_species_chart.png How are known species distributed into groups? Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College Why is maintaining earth’s biodiversity important to survival? Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College Biodiversity provides: • Natural Resources such as: food, water, wood, energy, and medicines • Natural (Ecosystem) Services including: air and water purification, soil fertility, waste disposal, biological pest control • Aesthetic pleasure Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College http://en.wikipedia.org/wiki/File:MEAConservationStrategies.jpg Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College “The only way to save the diversity of life and come to peace with nature is through a widely shared knowledge of biology and what the findings of that science imply for the human condition.” E. O. Wilson 2006 “The Creation” Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College How is biodiversity measured? • Richness is the number of unique taxa (species / organisms) • Abundance or relative abundance is the number of individuals present in each taxonomic group relative to the total number of individuals • Frequency is the percentage of times a species is observed • Community Dominance Index measures the proportion of the two most abundant species in a community. Higher Community Dominance Index values are generally found in ecologically degraded areas. • The Shannon-Wiener Index measures how evenly species (species evenness) within a community are distributed on a logarithmic scale. Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College http://en.wikipedia.org/wiki/File:Siberischer_tiger_de_edit02.jpg What causes changes in biodiversity? Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College “Animal and vegetable life is too complicated a problem for human intelligence to solve, and we can never know how wide a circle of disturbance we produce in the harmonies of nature when we throw the smallest pebble into the ocean of organic life.” George Perkins Marsh Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College Brainstorm: Factors that affect your life Grandfather Mom Art Dad Food Siblings Nature Ocean Skiing ME Colleagues Books Teachers Order factors according to impact each has had on your life and create a graphical representation. Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College Friends “The decline of Earth’s biodiversity is an unintended consequence of multiple factors that have been enhanced by human activity. They can be summarized by the acronym HIPPO, with the order of the letters corresponding to their rank in destructiveness.” E. O. Wilson, The Creation H Habitat loss, including that caused by human-induced climate change. I Invasive species harmful aliens, including predators, diseases, and competitors that displace native species P Pollution Oil spills, human agricultural waste, fertilization, pesticides, acid deposition, greenhouse gases etc P Population, Human overpopulation to be exact, a root cause of the other four factors O Overharvesting, Overuse hunting, fishing, gathering Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College Human Population Increase Land use change (Habitat loss) Increasing Economic Activity Increasing Economic Activity Increased use of technology Increased use of technology Social, political and cultural factors Social, political and cultural factors Indirect (Underlying causes) Direct causes Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College Declining Biological Diversity Habitat loss is the greatest reason for biodiversity loss. http://en.wikipedia.org/wiki/File:Lacanja_burn.JPG Habitat loss is due to: • Conversion of natural areas to farms, houses, etc • Fragmentation of ecosystems by human activities, housing, transportation, agriculture etc. • Simplification of genetic diversity and complex ecosystems by planting/selecting monocultures. Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College What are invasive species? Invasive Species cause major environmental and economical damage Invasive species, non-native species, invasive exotics, are introduced usually by human activities. Invasive species are generally thought to cause economic or environmental harm. http://en.wikipedia.org/wiki/File:Brown_tree_snake_Boiga_irregularis_2_USGS_Photograph.jpg Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College How are invasive species spread? Aquatic species may be transported in the ballast of ships or attach to the ship’s hull. Invasive species travel in the cargo of ships, planes, trains … The pet trade accidentally or intentionally spreads invasive species Many invasive species are released intentionally http://upload.wikimedia.org/wikipedia/commons/3/35/Zebra_mussel_GLERL_1.jpg • • • • Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College What are the characteristics of invasive species? • • • • • • • Grow rapidly Have high reproductive rates Disperse easily Tolerate a wide range of environmental conditions Flexible diet Limited naturally occurring predators Genetic and phenotypic variability http://en.wikipedia.org/wiki/File:LythrumSalicariaBig.jpg Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College What are the environmental costs of invasive species? • Invasive species are primarily responsible for 42% of species on the threatened or endangered species list. • Invasive species prey on native species (brown tree snake eating bird) • Nutrient cycles may be altered by invasive species making habitat less suitable to native species • Invasive species outcompete native species for resources (nutrients and space) • Loss of native species due to invasive species disrupts trophic relationships http://en.wikipedia.org/wiki/File:Birdsinging03182006.JPG Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College What are the economic costs of invasive species? • Estimates for damage and the cost of controlling invasive species in the United States exceeds $138 billion annually • Estimates do not include loss of biodiversity and ecosystem services provided by natural habitats http://en.wikipedia.org/wiki/File:One_US_dollar_1917.jpg Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College Are all invasive/introduced species harmful? • • • • Most introduced species are beneficial to society. Introduced species provide food, shelter, medicine, and aesthetic pleasure. Introduced species provide more than 98% of the United States food system Some organisms are introduced to control the populations of invasive species. http://en.wikipedia.org/wiki/File:Rice_p1160004.jpg Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College Population The expansion of human population (7 billion and counting) and affluence, especially in the developing world harms natural ecosystems. http://en.wikipedia.org/wiki/File:Population_curve.svg Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College Pollution http://en.wikipedia.org/wiki/File:AlfedPalmersmokestacks.jpg Pollution is the release of harmful substances into the environment. Pollution may include chemical substances, noise, heat, or light. Pollutants may be naturally occurring and harmful when they exceed natural levels. Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College Overexploitation / Overharvesting http://en.wikipedia.org/wiki/File:Bluefin-big.jpg Overexploitation refers to unsustainable harvesting of a renewable resource which can lead to the collapse of the population. This can result in extirpation and extinction. Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College http://upload.wikimedia.org/wikipedia/en/thumb/b/bc/Atlantic-Cod-Stocks.jpg/773px-Atlantic-Cod-Stocks.jpg References: Carroll, David M. (1999) Swampwalker’s journal: a wetlands year, Mariner Books, New York Jones, T. and and Laughlin, T. (2009) Learning to measure biodiversity: two agent-based models that simulate sampling methods & provide data for calculating diversity indices, The American Biology Teacher September 2009 vol 71 no 7 Miller Jr. G. Tyler (2007) Living in the environment: principals, connections, and solutions15th edition, Brooks/Cole California Raven, P., Berg, L., Hassenzahl, D. (2008) Environment 6/e, John Wiley & sons, New Jersey Wilson, Edward O. (1992) The diversity of life, W. W. Norton & Company, New York Wilson, Edward O. (1996) In search of nature, Island Press, Washington D.C. Wilson, Edward O. (2006) The creation: an appeal to save life on earth, W. W. Norton & Company, New York Life Sciences - HHMI Outreach. Copyright 2010 President and Fellows of Harvard College