STS Chap 8

• Biodiversity


  Variety of life, and refers collectively to variation at all levels of biological organization. Refers to the full abundance or variety of life – plant, animal and microbial. This variety of life occurs at all levels of ecological organization, but biodiversity generally refers to genetic, species and ecosystem diversity. This is the diversity of life upon which the health of the environment depends.
• Biodiversity is the foundation of human health
• Biodiversity


  • Securing the life-sustaining goods and services which biodiversity provides to us, the conservation and sustainable use of biodiversity can provide significant benefits for human health
  • The continuing loss of biodiversity on a global scale represents a direct threat to our health and well-being
  • Without a global environment that is healthy and capable of supporting a diversity of life, no human population can exist
• How biodiversity supports human health


  • Supports food security, dietary health, livelihood sustainability
  • Provides important resources for medical research
  • Provides important resources for traditional and modern medicine
  • Plays a role in the regulation and control of infectious diseases
  • Has social, cultural and spiritual importance within communities
• Genetic diversity in food systems


  Provides the foundation of crop development and food security, and promotes resistance and resilience to environmental stresses including pests and diseases of crops and livestock
• Diets based on a diversity of food species

  Promote health, and can help to protect against disease by addressing the problem of micronutrient and vitamin deficiencies
• Species of interest to medical science

  • Bears (for insights into osteoporosis, cardiovascular disorders, renal disease and diabetes)
  • Sharks (osmoregulation and immunology)
  • Cetaceans (respiration and treatments for divers suffering from decompression sickness)
  • Horseshoe crabs (optometry/ophthalmology and molecular biology)
• Biodiversity loss can impact on community traditions and livelihoods centered on traditional medicinal practices that utilize wild animals and plants, particularly for indigenous and local communities
• Millions of people depend upon traditional medicines for their primary health care
• Biodiversity loss and ecosystem change


  Can increase the risk of emergence or spread of infectious diseases in animals, plants and humans, including economically important livestock diseases, zoonotic outbreaks and global pandemics
• In recent years outbreaks of SARS, Ebola, Marburg, Hantavirus pulmonary syndrome, avian influenza and malaria have been attributed to human impacts on biodiversity, the wildlife trade or unsustainable land use change
• Without a greater understanding of disease ecology, there is also a risk that programmes to tackle infectious diseases which may impact negatively on biodiversity, through use of biocides and other chemicals and wildlife culls
• Ecosystem change


  Can result in disconnection of populations from open spaces or the wider countryside, with negative implications for physical and mental well-being and loss of "sense of place"
• Ecosystem change


  Has been linked to an increased prevalence of 'disease of affluence' (diabetes, obesity, cardio-pulmonary illness) and psychological disorders in many communities
• Access to 'greenspace' (natural and artificial)


  Are associated with better health outcomes, shorter hospital visits and reduced convalescence time for patients than purely urban environments
• An awareness of environmental values and respect for other species has been associated with reduced propensity towards anti-social behavior in children and young adults
• Threats to biodiversity


  • Habitat loss
  • Overharvesting
  • Invasive species
  • Climate change
• Habitat loss


  Humans rely on technology to modify their environment and make it habitable. Other species cannot do this. Elimination of their habitat—whether it is a forest, coral reef, grassland, or flowing river—will kill the individuals in the species.
• Overharvesting


  Overhunting, overfishing and overharvesting contribute greatly to the loss of biodiversity, killing off numerous species over the past several hundred years. Poaching and other forms of hunting for profit increase the risk of extinction; the extinction of an apex predator — or, a predator at the top of a food chain — can result in catastrophic consequences for ecosystems.
• Invasive species


  Exotic species are species that have been intentionally or unintentionally introduced by humans into an ecosystem in which they did not evolve. Most exotic species introductions probably fail because of the low number of individuals introduced or poor adaptation to the ecosystem they enter. Some species, however, have characteristics that can make them especially successful in a new ecosystem. These exotic species often undergo dramatic population increases in their new habitat and reset the ecological conditions in the new environment, threatening the species that exist there.
• Climate change


  Recognized as a major extinction threat, particularly when combined with other threats such as habitat loss, due to past and continuing emission of greenhouse gases, primarily carbon dioxide and methane, into the atmosphere caused by the burning of fossil fuels and deforestation. The warming trend will shift colder climates toward the north and south poles, forcing species to move (if possible) with their adapted climate norms. Changing climates also throw off the delicate timing adaptations that species have to seasonal food resources and breeding times.
• Biotechnology


  Set of techniques that involves the use of biological processes and living organisms for industry, agricultural or other activities. The purpose is to modify the natural and biological processes of living organisms without necessarily altering the genes or genetic construct of the living organisms. Has four major industrial processes based on biological systems, namely cell and tissue culture, fermentation, enzyme technology, and genetic engineering – also referred to as modern technology.
• Traditional modification methods


  Selective breeding and cross-breeding. Most of the foods today were created through traditional breeding methods which is time consuming and complex (difficult to make very specific changes).
• Genetic engineering


  Provided similar changes in a more specific way and shorter amount of time needed. Involves identifying the genetic information – or "gene" – that gives an organism (plant, animal or microorganism) a desired trait, copying the information from the organism that has the trait, and inserting that information into the DNA of another organism.
• Genetically Modified Organisms (GMOs)


  Common term used by consumers and popular media for genetically engineered organisms or foods that have been created through genetic engineering.
• Some Genetically Modified Organisms developed in the Philippines

  • Bt corn
• Bt corn


  Bacillus thuringiensis (Bt) is a soil bacterium that produces insecticidal toxins. Genes from Bt can be inserted into crop plants to make them capable of producing an insecticidal toxin and therefore resistant to certain pests. Bt corn in the Philippines was engineered to be specifically resistant to the Asian corn borer (ACB), Ostrinia furnacalis (Guenee), the most devastating corn pests in the industry.
• Adoption rate of biotech maize in 2015 is at 63 percent. In the period 2003 to 2015, there were 13 years of consecutive growth in hectarage of Bt corn, except for 2015 due to drought.
• Potential benefits of GM crops


  • Better nutritional qualities
  • Engineering pest or disease resistance in important crops
  • Edible vaccines
  • Antibodies engineered and produced in plants
  • Crops which can extract and detoxify pollutants from the environment
  • Crops which produce less toxic residues
  • Production of alternative polymers which can replace or substitute plastics and other petrochemical products
• Risks related to the use of GMOs


  • Potential impact on biodiversity
  • Potential for development of glyphosate-resistant weeds
  • Potential toxicity to non-target insect species
• Pro-GMO researchers


  Maintain that if crops are genetically modified for pest resistance, farmers can reduce their reliance on insecticides, so that local fauna, such as birds, rodents, and insects, can flourish in the area
• Secondary pests that would have been eliminated through widespread insecticide application


  Are not suppressed by the scaled-back insecticide use permitted GMOs, so other small predators - the birds and rodents that feed on the secondary pests - remain viable
• Development of drought-resistant or flood-resistant crops


  Allows arid or flood-prone land to be used for growing crops, meaning less high-biodiversity terrain needs to be converted for farming
• GMO skeptics have argued that up to 75% of plant genetic diversity has been lost since farmers switched to uniform GM crop varieties
• Less popular, non-GM seed varieties are being neglected
• Widely used GM crop varieties can spread to neighboring fields and eventually mix in with non-GM crops
• A farmer who wishes to continue using a non-GM seed variety, or who desires to maintain the organic status of his crops, must adopt potentially expensive measures to protect his crops from contamination or cross-pollination with his neighbor's GM crops
• Over-popularity of certain GM crops


  May lead to greater susceptibility to pests and disease
• Evolution of glyphosate-resistant weeds


  Has required farmers to make ever greater use of glyphosate, the toxicity of which poses dangers for human health
• It has been hypothesized that GM crops can harm insect species that are not pests