Chapter 3: Biodiversity Flashcards
Biodiversity
Refers to the variety of life on Earth.
Bio: living parts of an ecosystem
Diversity: # of species in an area and its relative abundance
Species Diversity
- variety of species per unit area
- measured with Simpsons
- in communities= # of species (richness) and relative proportions (evenness)
Comment on relative values of biodiversity. Why is the value of D in one area higher than the other one?
- pollution
- recent colonization
- agricultural management
Habitat Diversity
-Range of different habitats in and ecosystem/biome
-associated with variety of ecosystem niches
ex.
Low D: desert (sand/some vegetation)
High D: woodland (soil/river/trees)
Hotspot
Areas high in biodiversity
Genetic Diversity
Range of genetic material present in a population of a species or gene pool.
Ex.
Low genetic D: cheetahs (more prone to extinction, if env. changes, less likely to have genes to help survive
Gene Pool
Different types of genes in 1 individual.
Large gene pool=high genetic diversity
Conservation
Keeping what we have
Endemic Species
Species not found anywhere else (not widely spread, very specialized)
Increase/Conservation of habitat Diversity means
Increase/conservation in other 2 diversities
Speciation
Formation of a new species, when populations of a species become isolated and evolve differently
Fitness
How well an organism can survive and reproduce in its environment
Evolution
Development of new species over very long periods of geological time
Natural Selection
Nature does the choosing, unlike artificial selection (selective breeding)
Occurs when a population of 1 species has genetic diversity
Reproductive Isolation
Populations must become isolated from one another, so genes can’t be exchanged between them
Geographic Isolation
Physical barrier that cause populations to become separate
Cause of Isolation
-environmental change (Mountain formation) -change in river courses -sea level change -climatic change -plate movements
Plate Tectonics
Movement and forming of plates in surface of Earth.
Movement of Earth’s plates have caused:
- Isolation of populations
- creation of physical barriers
- land bridges
- climatic variations
- changes in food supplies
Types of Boundaries
- Convergent (collide)
Eurasian P.👉🏼Himalayas👈🏼Indian P. - Divergent (divide)
Pacific P.👈🏼Pacific-Antarctic Ridge👉🏼Antartic P. - Transform (neither destroy nor form)
African P.👆🏼Dead Sea Transform👇🏼Arabian P.
Mass Extinction
Period in which at least 75% of the total # of species on Earth are wiped out
Total: 5
Causes of Mass Extinction
All have been abiotic factors
- drop in sea levels (as glaciers formed)
- comets/asteroid impacts
- extreme climate change
How many species on Earth?
Total is unknown, but there are 1.8 million on museums
What are the current rates of species loss?
Between 30,000-60,000 species/year, and human activities increase this rate
Causes of Species loss
Natural:
- volcanos
- ice ages
- meteor impacts
Human
- pollution
- introduction of invasive species
- habitat destruction
- hunting
Conflict between exploitation, sustainable devices and conservation in LEDCs and MEDCs
Most tropical biomes occur in LEDCs, but they can’t sustain them since they don’t have the money. Activities like logging give the country and income, so there’s a debate. MEDCs can preserve, since they don’t rely on the forest’s income
Tropical Biomes contain:
some of the most globally biodiverse areas
The Red List
Shows threatened species in several categories
Factors that determine the conservation status:
- Population size
- Tropic level
- Distribution
- Quality of habitat
- Geographic range
- Probability of extinction
- Degree of fragmentation/specialization
- Reduction in population size
- Reproductive potential behavior
Arguments/Reasons for preserving Biodiversity
- Aesthetic
- Ecological
- Economic
- Ethical
- Social
Conservation Organizations
Non-Governmental Org. (NGO’s)
ex. Greenpeace
Intergovernmental Org. (IGO’s)
ex. UNEP
In Situ vs. Ex Situ
In Situ: conservation of species in their natural habitat
Ex Situ: “ outside their natural habitat
ex. Zoos
Designing Protected Areas
- Area (big)
- Edge Effects (big bc. pops. are bigger)
- Shape (circle)
- Corridors (to migrate)
- Buffer Zones (minimize disturbance from outside)
Successful protected areas should have:
PELHI
Partial/complete gov. funding Educational/management programs Local support High profile animals Involvent of gov. agencies
Species-based conservation strategies
CITES
Zoos
Protected Areas
CITES (Contention in International Trade in Endangered Species)
- international agreement
- aimed in regulating trade in endangered species
Umbrella species
Within the umbrella species, others inside the umbrella are protected
Flagship species
‘Charismatic’ species that appeal to the public
Keystone species
Species that plays a unique/crucial role in the ecosystem
Threats to species
Trade in souvenirs Fashion Habitat loss Medicine Exotic pet trades
Saved Species Description Ecological Role Pressure on Species Methods of Restoring Pop.
Island Fox
Description
-small fox
-Lives in SOMETHING islands on California
-brownish fur coat on its head, reddish on sides and white on belly
-feeds on insects and fruits
Ecological Role
-as deer mice and land birds inc., island fox dec.
Pressure on Species
-since the bald eagle was gone of the island, so people introduced the golden eagle, but they started to feed on the foxes, killing them rapidly.
Methods of Restoring Pop.
-conservation efforts made people reintroduced the bald eagle, and the golden eagle was relocated
-foxes started to breed again until they were no longer on the Endangered classification
Endangered Species Description Ecological Role Pressure on Species Methods of Restoring Pop.
Red Panda
Description
-Lives in South East Asia in countries like Bhutan and China
-they have a unique red/brownish fur coat (camouflage) and pointy ears, as well as a long tale used for balance
-live near water and feed on small seeds and fruits
Ecological Role
-they are the Ambassadors of clean air and water for millions of people
-
Pressure on Species
Methods of Restoring Pop.
