Conservation and Biodiversity 4.1 Biodiversity in ecosystems

Assessment Statements 4.1.1 Define the terms biodiversity, genetic diversity, species diversity, and habitat diversity 4.1.2 Outline the mechanism of natural selection as a possible driving force for speciation. 4.1.3 State that isolation can lead to different species being produced that are unable to interbreed to yield fertile offspring. 4.1.4 Explain how plate activity has influenced evolution and biodiversity. 4.1.5 Explain the relationships among ecosystem stability, diversity, succession and habitat.

Genetic Diversity: Different genetic characteristics of a species. 4.1.1 Define the terms biodiversity, genetic diversity, species diversity, and habitat diversity Biodiversity: amount of biological or living diversity per unit area. Consists of species, habitat, and genetic diversity Genetic Diversity: Different genetic characteristics of a species. Cheetah populations have very low diversity, due to inbreeding

4.1.1 Define the terms biodiversity, genetic diversity, species diversity, and habitat diversity Species diversity – the variety of species per unit area; includes the number of species present and their relative abundance.

4.1.1 Define the terms biodiversity, genetic diversity, species diversity, and habitat diversity Habitat Diversity: The amount of habitats or niches in a given area Variety of forests, deserts, grasslands, lakes, oceans, coral reefs, wet lands, and other biological communities. Chaparral Coniferous forest dessert grasslands deciduous forest

Biodiversity: Why should we care? Diverse ecosystems are more stable and more healthy More resistant to damage from factors like climate change and spread of disease Provides important ecological services to humans Biodiversity is useful to us as humans Recreation Food Goods Medicine

Ecological Services of Biodiversity Flow of material, energy in the biosphere Photosynthesis Pollination Soil formation and maintenance Nutrient cycling Moderation of weather extremes Purification of air and water

Important “stuff” From biodiversity Food, fuel, ecosystems, species, fiber, lumber, paper…. 90% of all food crops 40% of all medicines and 85% of all antibiotics Willow Tree - Aspirin Pacific Yew – Taxol (cancer drug)

Biodiversity of Species

Each Species and Process… Is key to the overall function of earth In general Diversity = Stability Biodiversity is Nature’s insurance policy against change The source of all natural capital for human use The way chemical materials are cycled and purified The end result of millions of years of evolution and irreplaceable

The 19 Most Biodiverse countries in the world. China Myanmar India Mexico Venezuela Costa Rica Philippines Colombia Cameroon Ethiopia Ecuador Malaysia Zaire Brazil Peru Indonesia Madagascar Australia South Africa The 19 Most Biodiverse countries in the world. What is the Problem with this?

Biodiversity Hotspots need special consideration Polynesia and Micronesia island complex Caucasus Mountains of south central China Mediterranean basin California Floristic Province Indo- Burma Meso-american forests Philippines Caribbean Eastern Arc Mountains and coastal forests of Kenya and Tanzania Brazillian Cerrado Choco/Darien/ western Ecuador Guinean forests of West Africa Western Ghats and Sri Lanka Wallacea Sundaland Tropical Andes Succulent Karoo Brazil's Atlantic forests Madagascar/ Indian Ocean islands New Caledonia Polynesia and Micronesia island complex Central Chile Cape Floristic region of South Africa Southwest Australia New Zealand Biodiversity Hotspots need special consideration

Hotspots These areas need emergency conservation attention Especially rich in endemic plant and animal species (found nowhere else in the world) They cover on 1.4% of world land area Mostly tropical forests Contain 60% of identified terrestrial biodiversity 55% of all primates, 22% of all carnivores 1.1 billion people living in poverty near these sites $500 million annually would go far to ensure their preservation

Diversity includes Richness: The number of species per sample is a measure of richness.  The more species present in a sample, the “richer” the sample. Evenness: A measure of the relative abundance of the different species making up the richness of an area.

Which sample is more diverse? Flower Species Sample 1 Sample 2 Daisy 300 20 Dandelion 335 49 Buttercup 365 931 Total 1000 Which has a higher richness? Evenness?

Quantifiying this Diversity – Simpson’s Index D = N (N – 1) ∑ n (n – 1) Where D = diversity index N = total # of organisms of all species n = # of individuals of particular species

Now practice the simpson’s index Species Number (n) n (n – 1) Woodrush 2 Holly seedlings 8 Bramble 1 Yorkshire Fog Sedge 3 Total (N)

Now practice the simpson’s index Species Number (n) n (n – 1) Woodrush 2 Holly seedlings 8 Bramble 1 Yorkshire Fog Sedge 3 Total (N) 15

Now practice the simpson’s index Species Number (n) n (n – 1) Woodrush 2 Holly seedlings 8 56 Bramble 1 Yorkshire Fog Sedge 3 6 Total (N) 15 64 15(14) / 64 =3.28

High values of “D” suggests a stable and ancient site A low value of “D” could suggest pollution, recent colonization, or agricultural management Index normally used in studies of vegetation but can be applied to comparisons of diversity of any species

How does diversity exist? Natural Selection = survival of the fittest Fitness = a measure of reproductive success If all individuals are variable And populations produce large numbers of offspring without increase in population size And resources are limited And traits are heritable

How does diversity exist? Those individuals who are best adapted to the environment will survive and pass on their genes Gradually the gene frequency in the population will represent more of these “fit” individuals