Sustaining Diversity

Question 1

biodiversity loss

Answer 1

natural process of fluctuations thru extinction events and renewals, as species pops decline, species are increasingly under threat (are vulnerable, threatened, endangered, extirpated, and extinct)

Question 2

extirpation

Answer 2

loss of a species from a part of its normal range

Question 3

extinction

Answer 3

irreversible loss of a species, has been accelerating and more species are threatened due to habitat loss and constrictions

Question 4

key catastrophic events

Answer 4

• Permian-Triassic Event (The Great Dying): was the most devastating
• Triassic-Jurassic Event: dinosaurs
• Cretaceous-Paleogene Event

Question 5

Anthropocene Event

Answer 5

we are currently believed to be in the 6th mass extinction event, caused by exponential growth of human pop and ecological footprint which has outgrown Earth’s carrying capacity, rate of extinction is increasing alongside the growth of human pop

Question 6

functional extinction

Answer 6

species that are eventually going extinct due to a lack of genetic variability and viable reproduction

Question 7

factors of vulnerability to extinction

Answer 7

• low reproductive rates and long lifespans
• specialized niches
• narrow distribution
• feeds at high trophic levels (apex predators)
• fixed migratory patterns (disturbances in patterns endangers species)
• rare and specialized (often found on islands with distinct, isolated species that make unique species)
• commercially valuable
• large territories (requires a lot of land and, if encroached, the species is confined to a smaller area and this changes relationships and puts them at risk)

Question 8

factors of habitat degradation

Answer 8

• changes in land/sea use (encroaching natural habitats)
• overexploitation (hunting, poaching, etc.)
• invasive species and disease
• pollution
• c.c.

Question 9

examples of human causes of biodiversity loss

Answer 9

• overharvesting
• resource extraction exceeding rates of renewal
• target a small number of species but activities have a wide range of indirect effects (by decimating one part of the system, the rest suffer consequences)
• ecosystem simplification (gets rid of niches that animals are reliant on)
• habitat fragmentation (breaking down habitats into smaller ones, decreases habitat, movement, and biodiversity due to a lack of genetic material and isolation)
• invasive species (adds competition for resources)
• pollution (alters matter cycles and storage pools, introduces toxins, stressors, and disturbances which impact species mortality and vitality)

Question 10

characteristics of successful invader species

Answer 10

high reproductive rate/short generation time
- pioneer species
- long-lived high dispersal rate
- release growth inhibiting chemicals into soil
- generalists
- high genetic variability

Question 11

characteristics of ecosystems vulnerable to invader species

Answer 11

• similar climate to natural habitat of the invader
• early successional systems
• low diversity of native species
• absence of fires
• disturbed by human activities

Question 12

the value of biodiversity

Answer 12

• intrinsic: all species have an inherent right to exist, should promote non-monetary, ethical perspectives on treating animals and the env
• ecological values: ecosystems have functions and integrity, the stability and resilience of a system depends on biodiversity, provides ecological services like air water, soil, nutrients, energy flows (biodiversity sustains us thry providing provisions, regulation, cultural, and support)
• utilitarian: provides livable conditions, harvestable resources, genetic info, spiritual and aesthetic value, and non-consumptive resource uses (like recreation, education, ecotourism)

Question 13

mitigation

Answer 13

alleviating the effects, involves a hierarchy of approaches (avoiding causing a problem, minimizing losses by limiting the magnitude of impacts, restoring damaged and degraded systems, compensating thru replacement or substitution)

Question 14

2 approaches to mitigation

Answer 14

• species approach
• ecosystem approach

Question 15

species mitigation

Answer 15

goal is to protect species from extinction, identify endangered species and threats, habitat management, propagate endangered species in captivity, reintroduce species in suitable habitats, raise awareness to save endangered species; involves things like zoos, aquariums, gene and seed banks, legal protection, etc.

Question 16

ecosystem mitigation

Answer 16

goal is to protect habitats and diverse ecosystems, preservation habitats in diff biomes and systems, habitat protection areas (protected areas, sustainable management, restoration ecology)