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PER 9. 1)Hand-in Mining lab M. Choice, Matching, Fill-ins. Tests back Tomorrow HW: Cha. 16 S. Answer. PER 8/9. Today 2/13/07 1)Hand-in Chapter 16 S. Answer 2) Lab: Relationships & Biodiversity. Tests back Today HW: Cha. 16 Critical Thinking. PER 9. Today 2/15/07
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PER 9 1)Hand-in Mining lab M. Choice, Matching, Fill-ins. Tests back Tomorrow HW: Cha. 16 S. Answer
PER 8/9 Today 2/13/07 1)Hand-in Chapter 16 S. Answer 2) Lab: Relationships & Biodiversity. Tests back Today HW: Cha. 16 Critical Thinking.
PER 9 Today 2/15/07 1)Hand-in Chapter 16 work 2)Finish Relationships/Biodiversity Lab
Preserving Earth’s Biological Diversity Chapter 17
Do Now: • Identify and explain the significance of the various components of biological diversity. • Supply one specific example of each type of diversity in your explanation. THINK: biological diversity genetic diversity species richness ecosystem diversity
Do Now: Answer and examples • Variation among organisms is referred to as biological diversity. • The components of biological diversity include genetic diversity, species richness, and ecosystem diversity. • Genetic diversity takes into account the genetic variety within all populations of that species. These differences provide a broad genetic base for each species’ long-term health and survival. *If all members of a species were genetically identical, then they would all be susceptible to the same pests and disease. • However, a corn blight fungus that ruined the corn crop in the U.S. in 1970 was brought under control by crossing the cultivated, highly uniform corn varieties with genetically diverse ancestral varieties from Mexico, making the resulting varieties resistant to the fungus. • Species richness refers to the number of species found in an ecosystem. • Species richness within an ecosystem provides the ecosystem with resilience, the ability to recover from environmental disasters. The removal of one species from a community makes an ecosystem run less smoothly. • Ecosystem diversity is the variety of interactions among organisms in natural communities, including forests, prairies, deserts, coral reefs, lakes, coastal estuaries and other ecosystems. A forest community with trees, shrubs, vines, insects, worms, animals, fungi and bacteria has greater ecosystem diversity than a cornfield.
Biological Diversity • Why We Need Organisms • Ecosystem Services and Species Richness • Genetic Reserves • Scientific Importance of Genetic Diversity • Medicinal, Agricultural, and Industrial Importance of Organisms • Aesthetic, Ethical, and Spiritual Value of Organisms
Species Richness Genetic Diversity Biological Diversity • Biodiversity
Species Richness Genetic Diversity Ecosystem Diversity Biological Diversity • Biodiversity
Why we need organisms • Biological diversity: the number and variety of organisms. • Genetic diversity: variation within a species. • Species richness: the number of species • Ecosystem diversity: variation within an ecosystem.
Why we need organisms • 270,000 plant species • 45,000 vertebrate species • 950,000 insect species! • 10,000 new species identified each year.
Where is declining Biological Diversity the Greatest problem? • Drastic loss biological diversity is occurring worldwide. • Tropical areas are more susceptible to species loss.
Maintains smaller fish populations by eating gar Nests eventually become small islands of trees Digs underwater holes used by other aquatic organisms Gator trails clear out aquatic vegetation Ecosystem Services and Species Richness • Why We Need Organisms • Ecosystem Services and Species Richness
Ecosystem Services & Organisms • Organisms provide essential ecosystem services. • Ex: Florida Alligators • Bacteria and Fungi are decomposers that cleanse and recycle nutrients within an ecosystem. • Forests recharge groundwater, hold soil, act as a C sink.
I. How many Species are there? • 99.95 % of species that have existed are now extinct. • ~1.8 million species identified at present. • # may range from 5-100 million species, we don’t know.
Genetic ReservesScientific Importance of Genetic Diversity • How to avoid a Corn Blight? • Increased genetic variety increases the chance that Zea mays will survive changing conditions in nature.
Scientific Importance of Genetic Diversity • Genetic Engineering • Bacterial derived Human Insulin • Bacterial derived Human Growth Hormones • Microevolution
Medicinal, Agricultural, & Industrial Importance of Organisms • Penicillium fungus: Penicillin based drugs • Rosy Periwinkle: increased child leukemia survivorship 5%95% • Sponge derived compound used in AZT (aids drug) • Beetles: Steroids • Centipedes: fungicide for crops
II. Why we need organisms Medicinal, Agricultural, & Industrial Importance of Organisms Salix babylonica • Aspirin • The discovery of aspirin dates back to the 5th century B.C., when Hippocrates used a powder from the bark of a willow tree to ease minor pains, reduce fevers and to help with childbirth. The willow tree contains salicylic acid which is similar to acetylsalicylic acid (aspirin).
Do Now: • Define extinction and give the possible causes of mass extinction. What single human activity increases the susceptibility of a given species to extinction? Provide the ways?
Do Now: Answer • Extinction is the irreversible elimination of a species from Earth. The causes of past mass extinctions are not well understood, however possible causes include a major climate change or a catastrophic collision of Earth and a large asteroid or comet. • Human activity disrupts or destroys the habitat of many organisms. If an organism’s habitat is altered, this impacts the organism's ability to find a mate, food sources, and territory necessary for survival and shelter. • Some species have an extremely small range and when this is disturbed, the species will perish
Human Causes of Species Endangerment • Most human activities contribute to a reduction in biological diversity • Habitat Destruction is the major cause of the current decline in biological diversity. • This loss of habitat reduces a species biological range & ability to survive!!!!!!!!!!!!!!!!!!!!!!!!!
Endangered & threatened Species • Extinction: the permanent loss of a species, therefore a permanent loss in species diversity. • Background extinction: continual low level extinction • Mass extinction: numerous species disappear during a relative short period of time • Marine organisms being temperature sensitive • Human population growth and consequent habitat destruction of the Dusky sparrow
Continuous, slow rate of extinction over millions of years Numerous species disappear over geologically short time frame. Endangered and threatened Species • Background Extinction vs. Mass Extinction
Endangered & threatened Species • Extinction: the permanent loss of a species, therefore a permanent loss in species diversity. • An endangered speciesnumbers are reduced so that they are in danger of extinction throughout all or a significant part of their range.
Could become extinct soon. Population declining very fast. Endangered and Extinct Species • Endangered and Threatened Species
Endangered & threatened Species • Threatened species: when extinction is less imminent but its population is quite low. • Species likely to become endangered in the foreseeable future, throughout all or a significant portion of its range
Endangered & threatened Species Protected Species Threatened species endangered species Extinct Species
Endangered & threatened Species • What factors are common with most Endangered & threatened species? Gymnogyps californianus
Endangered & threatened Species • Endangered & threatened species often have: • Limited natural ranges • Low population densities. • Low reproductive rates • Very specialized nutritional or reproductive requirements.
Characteristics of Endangered Species Tiburon mariposa lily • Extremely small range • Requiring large territories • Living on islands • Low reproductive success • Specialized breeding areas • Specialized feeding habits California condor Hawaii O-o, Moho nobilis Blue whale Green sea turtle Giant panda
Hawaii O-o, Moho nobilis • Hawai'i 'O'oMoho nobilis was only found in forest on the big island of Hawai'i, USA. It was last collected in 1898 and last seen in 1934, with its decline to extinction presumably caused by both habitat destruction and disease.
Bears http://www.iucn.org/ http://www.iucnredlist.org/search/details.php/13625/all
Do Now: • What does it mean that a species is endemic? Name a species that is endemic to your bioregion.
Do Now: Answers • endemic = native to a limited area and not found naturally outside that area
Endangered & threatened Species • Endemic species: species found only in one spot in the world • 171 extinct bird species • 155 of them lived on islands • Leads to habitat fragmentation
Do Now: • What are some Human Causes of Species Endangerment?
Do Now: • habitat destruction, • fragmentation, degradation, Deforestation • Invasive species (biotic pollution) • competition • Pollution • Water, air, land, Biocide use • Acid rain, ozone depletion, climate change • Overexploitation, • commercial harvesting • Ivory, pet trade, scientific whaling
Endangered & threatened Species • Many island species are Endangered species. • “Island” isolated habitat surrounded by unsuitable territory • Habitat fragmentation: the break up of large areas of habitat into small, isolated patches (islands) is a major threat to the long-term survival of many species.
Habitat fragmentationand how the Cow birds love it • Not a deep woodland bird until loggers come. • North America's most notorious brood parasite • Cowbirds have parasitized over 220 host species 150 reared by host species, with songbirds comprising the majority of hosts. • Examples: • Black-capped Vireo: 90% of nests parasitized in open canyon woodlands on Fort Hood, Texas (Eckrich et al.). • Bell's Vireo and Yellow-breasted Chat: 80-90% of nests parasitized in desert riparian habitat in the lower Colorado River valley (Averill et al.).
Confirmed observation in Arkansas in April 2005 Endangered and Extinct Species
Endangered and Extinct Species Where is Declining Biological Diversity the Greatest Problem? • In US: Hawaii and California • Worldwide: Tropical rain forests • 7% of earth's surface containing almost 50% species
Endangered and Extinct Species • Earth’s Biodiversity Hotspots
#1 cause: Habitat Destruction, Fragmentation, and Degradation Endangered and Extinct Species • Human Causes of Species Endangerment