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1 Web-based Course วิชา ความหลากหลายทางชีวภาพ ในประเทศไทย (Biodiversity in Thailand)
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2 สถาบันบัณฑิตวิทยาศาสตร์และ เทคโนโลยีไทย ( สบวท.) Thailand Graduate Institute of Science and Technology (TGIST) www.learn.in.th LearnOnline@learn.in.th
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3 สำนักงานพัฒนาวิทยาศาสตร์และ เทคโนโลยีแห่งชาติ National Science and Technology Development Agency
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4 Prof. Dr. Warren Y. Brockelman Mahidol University Bangkok, Thailand
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5 Biodiversity Genetics Evolution Ecology Taxonomy Environmental Sciences Molecular biology Biotechnology
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6 Causes of Extinction of Species Habitat destruction Pollution Over Hunting Current Rate of over Extinction ~ 1000 times the Natural Rate The majority of species will become extinct before we will able to study or use them (Natural Rate ~1 per 1-10 million species /year)
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7 “Biodiversity” = all the systems of living things (DNA, genes, individuals, species, communities, and ecosystems) Saving as many species as possible The improvement of our lives and our very survival (biotechnology, genetic engineering, ecosystem function, beauty,...)
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8 Food diversity
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9 Hidden products
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10 Speicies diversity
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11 Genes to ecosystems
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12 Within species diversity Genetic variation Races Subspecies (geographic variation)
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13 Genetic Variation: Each individual is genetically distinct Measured by detecting variation in enzymes or proteins (direct products of genes) Measured by analyzing for differences in nucleotide sequences
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14 Ecosystem Variability: = the differences in structure, productivity and nutrient cycles in communities in different types of environment and climatic zones of the Earth
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15 Ecosystem function is vital to all living things Nitrogen cycle Carbon cycle
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16 History of Life 3.7 billion years The first living things 3.6 billion years aquatic cyanobacteria 2.5 billion yearsplanktonic plants (O 2 ) 400 Myafishes 300 Mya land plants, insects amphibians, reptiles 150 Myafirst birds, mammals 65 Myamammal radiations 2 Myaprimitive humans
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18 History of the Earth (continue) 245 Mya The regign of dinosaurs, until their extinction caused by collision of a large asteroid 65 Mya with Earth But normal rate of extinction approximately 1 species per 1-10 million per year
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19 Evolution over millions of years Changes in populations through time Speciation (branching), due to Species diversity Separation (geographic speciation) Reproductive isolation
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20 Species: distinct types of organisms with reproductively separate populations Each species: has distinct scientific name (Genus and species name) We are: Homo Sapiens Number of species in an areas is the most useful measure of biodiversity
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21 How many species are there on Earth ? 5 to over 15 million species But only 1.5 million species have been described so far insects = 2/3 of all species vertebrates = 40,000 species vascular plants = 270,000 species invertebrates=? fungi and microorganisms =?
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22 Charles Darwin Era (Natural Selection): Individual Variation Inheritance from parents to offspring Population growth and competition Survival of the fittest Evolutionary Change
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23 Important genetic principles Particulate inheritance “Genes” come in pairs Dominance Independent assortment
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24 Quantitative inheritance
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25 By 2000: Genetics, Molecular Biology genes and chromosomes mutation recombination gene frequencies and selection DNA structure and replication transcription (protein formation) nucleotide sequence
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26 DNA codes for protein s
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27 A continuing controversy : Is evolution gradual or sudden?
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29 Genetic analysis reveals phylogeny
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30 99% of all species that ever evolued are now extinct
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32 The study of biodiversity above the species level Population study Ecological communities Interactions (Stability & Diversity of communities) - herbivores and plants - predators and prey - trees and seed dispersers - pollinators and plants - fungi and roots Ecosystem function and diversity
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33 Communities consist of many interactions Nutrients plants herbivores predator diseasesdecomposer dispersal migration genetic change
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34 The flow of energy through a community
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35 Species diversity in a community Local extinction Colonization of immigrants Number of species on islands affected by:
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36 Causes of Extinction Fragmented forest Small species population sizes Species at most risk of extinction Low rate of population increase Poor dispersal ability Low natural density Hunted for their valuable parts In vanishing habitats
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37 Causes of Species loss Tropical forest destruction Forest fragmentation Hunting Pollution Damming and Canalization of rivers Half the species on Earth (by next few centuries)
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38 Why save species?: Because Direct use to humans Maintain ecosystems for survival of humans If we lose species cannot be recreated loss of potential values or uses: food chemicals genes natural beauty ecosystem stability
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39 How to slow down the extinction of species Reduction of human population increase Conservation of natural ecosystems as “ protected areas” Reduction of rural poverty Special breeding programs for critical species Reduction of pollution and disturbance of rivers Diversification of forestry and agriculture to reduce monocultures
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40 Why save biodiversity? The answer is: you tell us! Why do you want to save it? Some general reasons
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41 Because it pays. Many people make a living harvesting plants and animals, and using wildlife also. While this may not apply to you, it is wrong to destroy animals and plants that others need to make their living from. Because we are part of an ecosystem that sustains us, by providing services such as clean water and air, rainfall, fertile soil, and pest control. Destroying animals and plants will ultimately harm us. We do not have a natural right to destroy anything in nature, any more than we have a right to kill other people.
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