GettingTheMeasureOfB iodiversity

GETTING THE MEASURE OF BIODIVERSITY: 

GETTING THE MEASURE OF BIODIVERSITY RACHAEL BECKSTRAND PHILIP COSTASCHUK

Main Ideas : 

Main Ideas How to define ‘biodiversity’? Ways to measure biodiversity Biodiversity and the relationship to the way ecosystems function Taxonomic methods used in relation to quantifying and studying biodiversity Problems in general Conclusion Questions?

How do we define ‘biodiversity’?: 

How do we define ‘biodiversity’? The sum of all biotic variation from the level of genes to ecosystems. The number, variety, and variability of living organisms in a quantified area.

Methods to Measure Biodiversity: 

Methods to Measure Biodiversity Species Richness Species Evenness Disparity Species Rarity Genetic Variability.

Measuring Biodiversity…: 

Measuring Biodiversity… Species Richness; the total number of given species in a quantified area. Species Evenness; the degree to which the number of individual organisms are evenly divided between different species of the community. www.nature.com/cgi-taf

Measuring Biodiversity…: 

Measuring Biodiversity… Disparity; measures the phenotypic differences among species resulting from the differences genes within a population. Species Rarity; the rarity of individual organisms within a quantified area. http://www.rit.edu/~rhrsbi/GalapagosPages/DarwinFinch.html

Biodiversity & Genetics: 

Biodiversity & Genetics Genetic Variability: each population of a species contributes to additional biodiversity due to variations between genes. http://magma.nationalgeographic.com/ngm/bestwildlife/wallpaper13.html

Biodiversity and the Relationship to Ecosystem Functions: 

Biodiversity and the Relationship to Ecosystem Functions Diverse communities are typically more stable and function more efficiently. Loss of a umbrella species leads to a unoccupied niche, in turn potentially affecting ecosystem processes. Extinction events are commonly followed by high rates of diversification. Ex) Species turnover

Productivity: 

Productivity Increase of productivity in an area corresponds with an increase in biodiversity. Ex) tropical rain forest compared to semi-desert or tundra http://www.rainforest.org/projects/balamna/balamna.html

Biodiversity & Exotic Species;: 

Biodiversity & Exotic Species; Ecosystems with high measures of biodiversity are more resistant to invader species. Ex) Cheatgrass & Tamarisk http://tncweeds.ucdavis.edu/ http://tncweeds.ucdavis.edu/photos

Keystone & Umbrella Species: 

Keystone & Umbrella Species Species whose presence or resource requirements affect ecosystem functions. Health of an umbrella species is a way to monitor the health of an ecosystem. Ex) Northern Spotted Owl & Grizzly Bears

Taxonomy : 

Taxonomy New Discoveries Grouping together Splitting apart Phylogenies; showing past relationships between organisms using evolutionary lineages.

Increasing Species Worldwide: 

Increasing Species Worldwide Phylogenic Species Concept Computer databases Increased human exploration Technology; electron microscope and evidence using mDNA.

Species Richness: 

Species Richness www.nature.com/cgi-taf

Taxonomic methods used in relation to quantifying biodiversity: 

Taxonomic methods used in relation to quantifying biodiversity Phylogenic Species Concept Biological Species Concept Evolutionary Species Concept

Phylogenic Species Concept: 

Phylogenic Species Concept taxa are separate species if they can be diagnosed as distinct either by phenotypic or genotypic information. Leads to an increase in the number of species. Does not allow for natural variations within populations to be listed as separate species.

Biological Species Concept: 

Biological Species Concept Groups of organisms that can interbreed freely under natural conditions. Most commonly used of the three

Evolutionary Species Concept: 

Evolutionary Species Concept Groups organisms together using an ancestral/descendant relationship that is traceable in the fossil record Focuses on studying the morphological features of closely related organisms.

Problems in General: 

Problems in General Measuring biodiversity is ultimately a complex process involving many facets. Various applications of species concepts either divide and/or group organisms together. Biodiversity can’t be reduced to a single number. Studying biodiversity using all ecosystem processes at all scales. In attempting to preserve biodiversity we often are ‘speciesists’ ;favoring the cute and popular species.

Conclusions : 

Conclusions Generally, areas of higher productivity correlate with increases in biodiversity. Biodiversity is also measured using the genetic variability of different populations of a single species. Biodiversity can’t be reduced to a single number, thus creating complications when comparing biodiversity in different ecosystems. The importance of biodiversity is accepted by some and disregarded by many others.

QUESTIONS…: 

QUESTIONS… How do different taxonomic methods create potential problems in measuring biodiversity? How do difficulties in measuring biodiversity create complications for policy makers and administrative regulations? Can we study all processes at all scales? Why should anyone care about‘biodiversity’ ?

REFERENCES;: 

REFERENCES; Purvis, Andy. Hector, Andy. May 2000. Getting the Measure of Biodiversity. Nature Magazine. Vol.405 pgs 212-219. Berkshire, United Kingdom.www.nature.com/cgi-taf Wildland Invasive Species Team. July 2002.Vernal, UT. Retrieved on 10-26-02 http://tncweeds.ucdavis.edu/photos Macdonald, Glen. 2003. Biogeography; Introduction to Space, Time, and Life. New York. John Wiley & Sons Inc. Sartore, Joel. 2002. National Geographic Society. Retreived 10-20-02 http://magma.nationalgeographic.com/ngm/bestwildlife/ wallpaper13.html Dr. Robert Rothman: Darwin’s Finches. Retrieved on 10-18-02. http://www.rit.edu/~rhrsbi/GalapagosPages/DarwinFinch Paul Walker. Balam Na Project. Rainforest Preserve. 8-28-02 http://www.rainforest.org/projects/balamna/balamna.html      Paul Williams, 2002 ”Biodiversity: Measuring the variety of nature and selecting the priority areas for conservation.” London, 10/23/02, http://www.nhm.ac.uk/science/projects/worldmap/     Bryant, Peter J., 2001, “Biodiversity and Conservation: A Hypertext book”. Irvine, 10/23/02, http://darwin.bio.uci.edu/~sustain/bio65/Titlpage.htm#Table%20of%20contents Dooley, Laura Lee S., 1982-2002, “Biodiversity and Protected Areas”, Washington D.C., 10/23/03, http://www.wri.org/biodiv/

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