Unit 9 Exam Review

1. Unit 9 Exam Review

2. Conservation Biology – • Conservation may be defined as the management and sustainable use of the natural environment and natural resources for ethical reasons and the benefit of humanity. • Human history & habitat destruction – • Unsustainable land use practices have been around for thousands of years.

4. Preservationists – • Conservationists –

5. Three Guiding Principles of Conservation Biology: • Evolutionary Change – • Consequently the goal of this principle is to allow populations to change in response to environmental changes through adaptations. • Dynamic Ecology – • The ecological world is seen as dynamic; largely functioning through non-equilibrium principles. • Human Change – • Humans are participants within both na-tural and perturbed ecosystems and their presence within ecosystems needs to be recognized and accounted for.

6. Conservation Biology & Economics – • Three objectives of the World Conservation Strategy – • The maintenance of the ecological processes that life depends on; • The sustainable use of ecosystems and their component species; • The conservation of genetic diversity.

7. Conservation Biology, Standards of Living, and Human population – • Human expectations of a decent standard of living include food, shelter, water, space, education and a freedom of choice. • The problem of human pressure on natural resources is further complicated by the global problem of population growth.

8. Conservation & Self-Sufficiency – • Many countries that, a few years ago, were self-sufficient in food, now have to import food. • They tend to make extensive rather than intensive use of the land. • Landless people migrate to unoccupied public lands (i.e. natural vegetation). • Government indifference (as shown by their priorities) is one of the main causes of hunger.

9. Unnecessary Wastefulness & its Consequences – • Wastefulness is not the confined to the poor. Wealthy societies are even more wasteful. • In many developing countries, large tracts of land are wastefully cleared to provide exports to these wealthy countries. • The fishing industries of the wealthy nations have collapsed. The fishing industries of de-veloping countries have also collapsed due to local exploitation for export to the wealthy nations or their inability to police fishing rights leased to wealthy countries. • Overexploitation can become habitat destruction and cause species extinction. • The loss of tropical rainforests is serious. Other ecosystems under threat are wetlands, coastal areas, arid and semi-arid rangelands.

10. Genetic Diversity – • Diversity in traits/genetic code within a group of the same species • Species Diversity – • Many different species within the same community

11. Ecosystem Diversity – • Approximate number of known species on the planet – • Reasons for the above-mentioned uncertainty:

12. Adaptive radiation – • Latitudinal Gradient – • Extinction vs. Extirpation –

13. Background Extinction – • 1 species extinction per 500 to 1,000 years • Number of Mass Extinctions – • There have been 5 mass extinction events so far in earth’s history • We are currently in the 6th mass extinction • A mass extinction is defined as an event causing the death of more than half of the species on the planet • Habitat Alteration – • The intentional or accidental destruction or change in a habitat/niche • This is the leading cause of species extinction

14. Invasive Species – • Pollution – • Population Growth –

15. Overexploitation – • Biophilia – • Umbrella species –

16. Endangered Species Act (1973) • Captive Breeding – (zoos) • A strategy used to build up a declining population & potentially reintroduce a threatened species into the wild. • Very expensive & so far has only shown limited success (California condor)

17. Biodiversity Hotspot – • IUCN – • Extinct – • Extinct in the Wild –

18. Critically endangered – • Endangered – • Vulnerable –

19. Conservation Dependent – • Near Threatened – • Least Concerned –

20. Four Factors creating the Basis for the Concern over Extinction – • The unprecedented level of threats to biodiversity; • The escalation of the threats to biodiversity; • The observation that the threats to biodiversity are synergistic; • The realization that what harms biodiversity will harm humanity.

21. Population & Size & Survival – • Births and immigrations add to the population size while deaths and emigrations reduce the population size. • Population size and survival depend on: • The availability of resources • The amount of suitable habitat • Predation/parasitism • Disease • Social interactions

22. Mechanisms of Extinction in Single Populations – • Demographic uncertainty • Environmental uncertainty • ‘Natural’ catastrophes • Loss of genetic diversity • Mechanisms may interact, compounding the effect on the population. • Population size is critical to survival.

23. Minimum Viable Population – • the lowest number of individuals needed to ensure that a population has a selected probability of survival for a set time period without significant loss of evolutionary adaptability. • No MVP is applicable to all species.

24. Vulnerability to Extinction – • Species that only occur in threatened habitat types • Species that are economically valuable to humans • Species that do not have any/much experience of disturbance • Species requiring large home ranges