Chapter 55

1. Chapter 55 Conservation Biology and Restoration Ecology

2. Conservation Biology Definition: integrates ecology, physiology, molecular biology, genetics & evolutionary biology to conserve biological diversity at all levels. 1.) Must take into consideration social science, economics, politics, etc.

3. Restoration Ecology Definition: applies ecological principles in an effort to return degraded ecosystems to conditions as similar as possible to their natural, pre-degraded state.

4. Conservation biology & restoration ecology both play a role in trying to solve the… Biodiversity Crisis

5. Biodiversity Crisis A little background… 1.) Biodiversity: the # of different species in a particular ecosystem (or in the entire world). 2.) Scientists have described and named about 1.8 million species to date. 3.) They estimate there could be anywhere from 10 – 200 MILLION more species.

6. Biodiversity Crisis cont’d… 4.) Extinction is natural and has been occurring since the first living organism appeared on Earth. 5.) The current RATE of extinction is what is causing the “biodiversity crisis.” 6.) The primary cause of the current extinction rate is…HUMANS!

8. Biodiversity Crisis cont’d… Biodiversity has 3 main components/levels: 1.) Genetic diversity 2.) Species diversity 3.) Ecosystem diversity

9. Genetic Diversity 1.) Comprises not only the genetic variation within a population but also the genetic variation between populations. a.) Genetic variation b/w populations is associated with adaptations to each other & local conditions. b.) Loss of genetic diversity has human implications: i.) Example: If we lose populations of wild plants that are closely related to crop species, we lose genetic resources that could be used to improve crop quality through selective breeding or genetic engineering.

10. Species Diversity (Species Richness) 1.) Endangered species: those that are in danger of extinction throughout all or a significant portion of their range. a.) Threatened species: those that are likely to become endangered in the near future.

11. Species Diversity (Species Richness) cont’d… 2.) Depressing statistics: a.) 12% of bird species & 24% of mammal species are threatened with extinction. b.) 32% of amphibian species are endangered. c.) 20% of freshwater fish have become extinct (since we began keeping records) or are seriously threatened.

12. Species Diversity (Species Richness) cont’d… 3.) These numbers are just for known species – think about all the species that we haven’t even discovered that have either gone extinct or are endangered!

13. Ecosystem Diversity 1.) The variety of ecosystems – strongly tied to community structure. a.) The extinction of one species may have a dramatic affect on ecosystem (keystone species). b.) Each ecosystem has a characteristic energy flow & nutrient cycling system – some of which affect the entire biosphere! i.) Producers in large ecosystems may moderate temp for the whole biosphere by using carbon dioxide.

14. Why should we care about biodiversity loss?? 1.) Maybe, just maybe we should care about it because we are all citizens of this planet & should feel a sense of connection to nature & other forms of life. a.) This sense of connection is what FAMOUS ecologist E.O. Wilson calls “biophilia.” http://www.pbs.org/wgbh/nova/eowilson/program.html

15. Why should we care about biodiversity loss?? But, if you’re a JERK and need a more selfish & practical reason to care… 2.) Many threatened species are potential sources of crops, fibers & medicines that we can use. a.) 25% of all current prescription medications are derived from plant-produced chemicals. i.) Example: Compounds produced by certain species of periwinkle flower and by the pacific yew tree are used in chemotherapy.

16. Why should we care about biodiversity loss?? 3.) Losing biodiversity means losing genes & genetic diversity. a.) With their unique genetics, many organisms can be put to use by humans in genetic engineering. b.) Numerous prokaryotes are used for or produce products that are used in genetic engineering processes.

17. Time out – Review! Describe a procedure by which a human gene can be inserted into a prokaryote in order to produce a useful protein product.

18. Why should we care about biodiversity loss?? 4.) Loss of ecosystem services: all the processes through which natural ecosystems and the species they contain help sustain human life. a.) We have closely evolved with Earth’s ecosystems & they provide many important “services” such as: i.) purification of air & water ii.) reduction of the severity of droughts & floods iii.) generation/preservation of fertile soils iv.) decomposition of wastes v.) pollination of crops vi.) dispersal of seeds vii.) cycling of nutrients viii.) control of pests ix.) general beauty & recreation

19. Why should we care about biodiversity loss?? b.) If humans had to perform these services artificially and we had to pay for them, it would cost $33 trillion dollars per year! That’s more than all the countries on Earth make combined.

20. Threats to Biodiversity – what is causing the loss of species?? 1.) Habitat Destruction a.) Greatest threat to biodiversity b.) 98% of forests in Central America & Mexico have been cut down. c.) U.S. prairie covers 0.1% of its original range d.) 93% of coral reefs have been damaged – at current rate, 40-50 % of reefs and 1/3 of marine fish species will be lost in 30-40 years.

21. Threats to Biodiversity – what is causing the loss of species??

22. Threats to Biodiversity – what is causing the loss of species?? 2.) Introduced species: those that humans move, either intentionally or by accident from the species native locations to new regions. Also called invasive, nonnative or exotic species. a.) Ease of travel by plane/ship has increased this. b.) If introduced species gain a foothold in new region, they can disrupt native community by preying on or outcompeting native organisms.

23. Threats to Biodiversity – what is causing the loss of species?? Zebra mussels in the Great Lakes have disrupted the ecosystem, threatened native species & clogged city’s water supplies – causes billions in damage!

24. Threats to Biodiversity – what is causing the loss of species?? Kudzu vine - Introduced to control erosion in southern US – took over!

25. Threats to Biodiversity – what is causing the loss of species?? 3.) Overexploitation: the human harvesting of wild plants or animals at rates exceeding the ability of populations of those species to rebound. a.) Usually refers to commercial hunting, fishing, trading & collecting of animals.

26. Threats to Biodiversity – what is causing the loss of species?? Confiscated ivory from endangered elephants Japanese fish market- selling bluefin tuna

27. Threats to Biodiversity – what is causing the loss of species?? 4.) Disruption of interaction networks: ecosystems depend on interspecific community interactions. The extinction of one species can doom another to the same fate. a.) Example: bats called flying foxes are endangered due to hunting. They pollinate about 80% of plant species on the Samoan Islands!

28. Population Conservation Small Population Approach: emphasizes small pop size as ultimate cause of extinction. 1.) Once a population is small, what finally drives it to extinction? 2.) The extinction vortex: + feedback loops of inbreeding & genetic drift draw the population toward extinction.

29. Population Conservation 3.) Minimum Viable Population (MVP): the minimal population size at which a species is able to sustain its numbers and survive. a.) If you want to accurately calculate this, you really need to figure out the effective population size which is based on the breeding potential of the population (since not all members breed every year).

30. Population Conservation Declining Population Approach: emphasizes the environmental factors that caused a population’s decline in the first place. a.) Looks at populations that may be well above MVP but are showing a consistent pop decrease. b.) Seems simple…if deforestation is causing extinction then stop deforestation. If a human produced toxin is killing birds then remove toxin. It’s not always that simple….this is where science & society often intersect.

31. Read Concept 55.3 in your text about the establishment of protected areas & the identification of biodiversity hot spots.

32. Restoration Ecology 1.) Bioremediation: the used of living organisms (usually prokaryotes, fungi or plants) to detoxify polluted ecosystems. a.) Some plants can take up toxins left behind from mining. Plant & harvest them and remove toxins from soil. b.) Some bacteria can metabolize oil and clean up spills.

33. Restoration Ecology 2.) Biological augmentation: uses organisms to add essential materials to a degraded ecosystem. a.) Often uses plants that can grow in poor soil. When they die – enrich soil and help ecosystem to recover. *Take a look at pages 1226-1227 in book on restoration projects.*

34. Sustainable Development Definition: the long term prosperity of human societies AND the ecosystems that support them. Again, not just about science – to sustain ecosystems and retain biodiversity we have to connect to social science, economics & politics.

36. ??? 1.) Is it a moral & ethical responsibility to make individual & societal efforts to preserve biodiversity? 2.) What do you depend on other living organisms for on a daily basis? 3.) E.O. Wilson suggests that biophilia is innate: an evolutionary product of a brainy species whose survival depended on a close connection to the environment & the practical application of plants & animals. What do you think of this?