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Number of Species on Earth. 1,400,000 animal sp. 320,000 plant sp. Estimated # of tropical species (based on birds) = 2-3 x temperate = 2.8-4.2 million So total = 4.2-5.6 million. The Creator, if He exists, has "an inordinate fondness for beetles". – J.B.S. Haldane.
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Number of Species on Earth 1,400,000 animal sp. 320,000 plant sp. Estimated # of tropical species (based on birds) = 2-3 x temperate =2.8-4.2 million So total = 4.2-5.6 million The Creator, if He exists, has "an inordinate fondness for beetles". – J.B.S. Haldane 3/4 of all animals (>1 million species) are insects! Number of species in different animal groups
GEOGRAPHICAL DISTRIBUTION OF SPECIES: Terrestrial ecoregions Olson, D. M., et al (2001). Terrestrial ecoregions of the world: A new map of life on Earth.BioScience 51(11): 933-938. Ecoregion: a large area of land or water that contains a geographically distinct assemblage of natural communities that (a) share a large majority of their species and ecological dynamics; (b) share similar environmental conditions, and; (c) interact ecologically in ways that are critical for their long-term persistence.
52 Ecoregions in U.S. 261: California Coastal Chaparral Forest Shrub Province.
261: California Coastal Chaparral / Forest Shrub Province. • Climate. -- Hot, dry summers; rainy, mild winters. • Annual temperatures average 50º to 65 º F (10 º to 18 º C). • Annual precipitation 10-50 in. with a pronounced summer drought. • Some moisture from fog in summer. • Fire is common, usually set by lightning during the summer dry season. • Vegetation. • Riparian forest with many broadleaf species grows along streams. Willow, Mulefat • Sclerophyll forest on the hills and lower mountains. Live oak, white oak • Chaparral on steep hill and mountain slopes too dry to support oak woodland or oak forest. Chamise and various manzanitas. • Coastal Sage Scrub on exposed coastal areas. Buckwheat, Deerweed, Coyote bush, Black Sage, White Sage, California sagebrush, and bush lupine.
25 Biodiversity Hotspots 1.44% of the Earth's land surface, supporting ~70% of all plant species. Account for 44% of all plant diversity, 35% of all terrestrial vertebrate species, and 75% of all terrestrial animal species listed as threatened by the IUCN-World Conservation Union. California Floristic Province
CALIFORNIA • Biologically, most diverse state in the Union • 40,000 species • More federally listed (i.e. Endangered and Threatened) species than any other mainland state • Human population expected to grow from 32 million to 49 million by 2025
Endangered Species in the U.S. Southern California: a "hot spot" of threatened biodiversity Plants Birds Fish Molluscs (Dobson et al., Science 275, 550 (1997)
Threatened, Endangered and Candidate Species in California(terrestrial vertebrates)
Where have they gone? Forests - logged Native grasslands - converted to agriculture, overgrazed, invaded by exotics Wetlands - drained Streams - channelized and dammed Coastal sage scrub - converted to subdivisions, shopping malls, highways California's natural communities
Sclerophylls: leaves are small , hard, stiff, waxy, evergreen
Mediterranean ecosystems http://conserveonline.org/workspaces/global.med.assessment CA • Five distinct regions • Hot, dry summers and cool, wet winters. • 2.2% of the Earth's surface, but support 20% of the world's plant species. • >50% of the plant species are endemic: found nowhere else • All threatened by urbanization, land conversion, invasive species, altered fire regimes, excess grazing, tourism and climate change.
California Ecosystems Coastal Sage Scrub • 0-1500 feet elevation • California sagebrush (Artemesia californica), black sage, white sage, buckwheat and other drought-deciduous shrubs • ~90% lost to development • California Quail, Callipepla californica
Chaparral • 500-4,500 feet elevation. • Evergreen dense canopy 5-15 feet high containing chamise, manzanita, ceanothus, lemonade berry, scrub oak, toyon, mountain mahogany, yucca • Leaves contain flammable resins, but the plants are fire-adapted
Oak Woodland • 1,500-4,500 feet elevation. • Evergreen oaks and sycamores • Poison oak, elderberry, coffeeberry, manzanita.
Mixed Conifer Forest • > 4,500 feet elevation. • Coulter pine, jeffrey pine, white fir, Incense cedar, black oak, canyon live oak. Also shrubs and grasses • Huge losses to timber harvesting
Desert • East of the Peninsular Mountains • Low rainfall, high evaporation • Many plants are succulent: they store water in their stems and/or leaves • Creosote bush, desert willow, agave, indigo bush, chuparosa, beavertail cactus, cholla cacti, barrel cactus, smoke tree, saltbush, ocotillo, palo verde tree, desert fan palm, lupine, primrose, and verbena.
Riparian • Alongside streams and lakes • Willow, sycamore, cottonwood, mule fat. • Huge losses due to channelization and damming http://www.prbo.org/calpif/plans.html
Wetlands • Inundated or saturated by water at least part of the time. • Five major types: marine, estuarine, lakes (including vernal pools), rivers, and marshes, swamps and bogs. • Most lost to draining, filling, harbor development http://www.beachcalifornia.com/wetlands-california-birds-photos.html
Vernal Pools • Seasonally flooded depressions on an impermeable layer • Specially adapted plants that flower in succession as the pool dries, giving concentric rings of color