MST WEEK 9

• Biodiversity


  The diversity of genes, species, and ecosystems in a region
• Biodiversity is lost when populations are greatly reduced in size, when a species becomes extinct, or when ecosystems are destroyed or greatly modified
• Levels of biodiversity

  • Genetic
  • Species
  • Ecosystem
• Genetic diversity


  The total number of genetic characteristics of a specific species, subspecies, or group of species
• Population


  A group of individuals of the same species, living in the same area or interbreeding and sharing genetic information
• Species


  All individuals that are capable of interbreeding
• Factors influencing genetic diversity of a population

  1. Mutations

  2. Migration

  3. Sexual reproduction
• Sexual reproduction does not create new genetic information, but it tends to generate new genetic combinations
• Population size


  The smaller the population, the less genetic diversity it can contain and the fewer the variations in the genes for specific characteristics
• Selective breeding can affect the genetic diversity of a species
• Species diversity


  Measurement of the number of different species present in an area, which in turn has three qualities: Species' richness, Species' evenness, and Species' dominance
• Factors influencing species diversity of a location

  • Geologic and evolutionary history of a region
  • Migration introducing new species
  • Size of the area being considered
  • Human activity
• Tropical rainforests


  Have greater species diversity than Polar Regions
• Migration introducing new species


  Can increase species diversity, but some invading species can reduce species diversity by outcompeting original species
• Larger area being considered

  Larger the species diversity
• Human activity


  Has a great effect on the species diversity of a region
• Ecosystem Biodiversity Measurement


  Number of kinds of ecosystems present in an area
• Endemic organisms


  Exclusively native to a place of a biota
• Endangered species are present in such small numbers that they are at risk of extinction
• Philippine Eagle


  • Found in the rainforests of Isabela, Samar, Leyte and Mindanao
  • Similarities with Papua New Guinea's Harpy Eagle (Harpyopsis novaeguinea)
  • Considered as one of the world's largest Eagle
• Estimated population of Philippine Eagle is 100 to 300
• Philippine Eagle is in danger of extinction
• There are 400 exotic bird species in the Philippines, which, if not protected, would disappear from the face of the Earth
• Pygmy water buffalo (Bubalus mindorensis)


  • Endemic to Mindoro
  • Listed as one of the ten most endangered species in the world
  • Population went down from 10,000 heads in the 1900's to as few as 20 heads roaming in the wild today
• Philippine tarsier (Tarsius syrichta)


  • Measures only about twelve centimeters in length
  • Its two big eyes cannot move and do not have a tapetum the upper protective tissue
  • Can turn its head 180 degrees
  • Found in the islands of Samar, Leyte, Bohol and Mindanao
  • Got its name from its elongated Tarsus bone
• There are only about 1,000 tarsiers inhabiting the wilds of Corella town in Bohol province where the biggest concentration of these rare animals was once reported
• Characteristics of Organism Prone to Extinction

  • Small populations of dispersed individuals
  • Organism in small, restricted areas
  • Specialized organisms
  • Carnivores at higher trophic levels in food chains
• Characteristics extinction occurs when all the individuals of a complete eliminated
• Organism in small, restricted areas, such as islands, are also prone to extinction because an environmental change in their locale eliminate the entire species at once. Organisms scattered over large areas are much less likely to be negatively affected by one event
• Specialized organisms are more likely to become extinct then are generalized ones. Since specialized organisms rely on a tow key factors in the environment, anything that negatively affects these factors could result in their extinction, whereas generalists can use altemate resources
• World's largest pearl

  • Discovered by a Filipino diver in a giant Tridacna (mollusk) under the Palawan Sea in 1934
  • Known as the "Pearl of Lao-Tzu
  • Weighs 14 and measures.9 1/2 inches long and 5 1/2 inches
  • Valued at US$42 milion as of May 1984
  • Believed to be 600 years old
• The world's second deepest spot underwater is in the Philippines. This spot, known as the Philippine Deep or the sea level. The Philippine Deep is in the floor of the Mindanao Trench, is about 10,497meters or 34:440 feat below Philippine Sea
• World's Largest and Tiniest Shells

  • Tridacna gigas, one of the world's largest sheds
  • Pisidum, the world's tiniest shell
• Tridacna gigas grows as large as one meter in length and weighs id pounds
• Pisidum is less than 1 millimeter long
• Donsol


  A fishing town in Sorsogon province that serves as a sanctuary to a group of 40 whale sharks
• Whale sharks (Rhincodon typost)


  • Considered the largest fish in the world
  • Measure between 10 to 35 feet in length
  • Weigh about 20 tons
  • Locally known as "butanding"
  • Visit the waters of Donsol from November to May
• Philippine Cockatoo (Cacatua haernaturopygial)


  • One of the most endangered species in the Philippines
  • Belongs to Psittacidae of the Kalangay of the cidae of the fan of parrots
  • Can live up to 50 years
• Dwarf pygmy goby (Pandaka Pygmaea)


  • The world's shortest and lightest freshwater fish
  • Colorless and nearly transparent species
  • Found in the streams and lakes of Luzon
  • Males have an average length of 8.7 mm and weigh 4.5 mg
• Of the 500 known coral species in the world, 488 are found in the Philippines