Biodiversity, Evolution, Conservation Flashcards
Types of Biodiversity
Species, habitat, genetic
Biodiversity
The variety of life existing in a certain area
Species Diveristy
of species / organisms per unit area found in different habitats of the planet
Simpson’s Index
Indicates how many different species exist
-high values of “D” are more biodiverse, stable
-low values could suggest pollution, colonization, agricultural management
D = nk (nk-1) / N (N-1)
Richness
of species per sample
Relative Abundance
A measure of "eveness" of different species making up the richness of an area # of individual species / total individuals present
Habitat Diversity
Range of different habitats per unit in an ecosystem or biome
Genetic Diversity
Total # of genetic characteristics of a specific species within a population
-larger population = greater genetic diversity
Endemic Species
Species found in only one specific area of the world
Natural Selection
Survival of the fittest
Fitness
Measure of reproductive success
Assumptions of Natural Selection
- all individuals are variable in fitness
- population size remains stable over long periods
- resources are limited (more competition)
- traits are heritable
- individuals best adapted to environment will survive and pass on their genes
Charles Darwin
Studied different Finch species on Galapagos Islands
Theories of natural selection & variation
Natural Selection & Variation
Evolution occurs randomly in an individual (good, bad, neutral) and changes the gene pool.
Unfavorable genes will die out, leaving only “good” genes in pool
EX: peppered moth- as buildings got darker from soot, darker moths survived
Isolation
Seperation of populations Types: -temporal (temperature/season) -behavioral -reproductive -geographical -habitat
Plate Tectonics
Movement of the Earth to create valleys, mountains, new land masses
Mutations
Any change or random error in a DNA sequece (the hereditary material of a cell)
Mutations in sex cells are passed to offspring (if unicellular all are passed)
Traits aquired without change in DNA are not passed
Evolution: FARBM
- fish
- amphibians
- reptiles
- birds
- mammals
Importance of Biodiversity
- nature’s insurance policy against change
- source of all natural capital for human use
- way chemical materials are cycled & purified
- end result of millions of years of evolution & irreplaceable
Anthropocentrism
- diverse ecosystems = more stable / healthy
- more resistant to climate change & spread of diseases
- provides important ecological services
- used for recreation, foods, goods, medicine
Extinction
When there are no more individuals of a species still alive anywhere in the world
-99% of all species that were on the earth no longer exist
Endangered
Species at risk of extinction because there are so few left they might soon be wiped out altogether
End of Ordovician (440 mya)
- 2nd most devastating in earth’s history
- affected marine species
- probably from glaciation
Late Permian (225 mya)
-largest extinction
-95% of all marine species lost
Possible causes:
-Pangea continents merging
-global warming from volcanic eruptions glaciation
Cretaceous / Tertiary Extinction
- all dinosaurs & half other plants / animals extinct
- possible asteroid
- brought rise of mammals
Mass Extinction Causes
- plate tectonics
- super volcanoes
- climate changes
- meteorite impacts
Human Causes of Endangerment (HICOP)
- Habitat destruction / fragmentation
- Introduced species
- Climate change
- Overexploitation
- Pollution
Degradation
Reducing the quality of available habitat
EX: logging, agriculture, sewage
Fragmentation
Splitting a single, large, contiguous system into many disconnected areas
EX: road through wilderness, dam across river
Loss
Disappearing of an entire habitat
EX: paving natural area for building, praires to farmland
Invasive Species
Organisms that are living in an environment outside its normal range or natural environment
-many transported by accident
Biocontrol
Species transported intentionally to control other “problem” species populations
Characteristics:
-fast growth / reproduction
-wide range of environments
-usually harmful to environment
-outcompete native organisms for local food
-lead to extinction of natives
Overexploitation
Harvesting a renewable resource to the point of diminishing returns
EX: wild medicinal plants, grazing pastures, game animals, fish stock, forests, water aquifers
Pollution
Introduction of harmful materials into environment
-damage quality of air, water, land
EX: sulfar leads to excess acid in lakes, streams, and damages trees, soil
Red List
Developed by International Union for the Conservation of Nature (IUCN)
Purpose:
1. identify species of concern
2. identify species in need of conservation
3. catalogue plants / animals facing global extinction
4. raise awareness
Conservation: Status Factors
- population size
- trophic level
- degree of specialization
- geographic range & distribution
- reproductive potential & behavior
Solutions (3 R’s)
1. Replace biotourism, education 2. Regulate policy 3. Restore species survival plans, reserves, research
Convention on International Trade in Endangered Species (CITES)
- international agreement between governments
- ensure international trade does not threaten species in wild
Endangered Species Act (1973)
- protect & recover endangered species
- protects habitats
Earth Summit (Rio, 1992)
193 nations supporting Convention on Biological Diveristy’s goals of biodiversity conservation & sustainable use of natural resources
Kyoto Protocol
Commits state parties to reduce greenhouse gas emissions
Conservation of Nature-scapes
- save areas rich in endemic species
- mostly tropical forests, continetal shelves, coral reefs
- contains 60% of identified terrestrial biodiveristy
- **keystone species imprtant
Criteria for Researves
- size
- shape
- edge effects
- corridors
- proximity to potential human influence
Nature Preserve Example
Gateway National Recreation
Zoos
Educationional facilities that care for, conserve, provide public awareness
- Association of Zoos and Aquariums (AZA)
- special species survival plans
- EX: breeding programs
Zoos Advantages
- education
- increased scientific knowledge
- controlled environment to protect animals
- easy genetic monitoring
- captive breeding = high success
- high chance of offpsring surviving
- species held while habitat conserved
Zoos Disadvantages
- individuals forcibly taken from habitat
- captive populations = small gene pool
- captive animals can’t survive in wild as well
- ethical argument
Non-Governmental Organizations (NGOs)
Not run, funded, or influenced by national governments
EX: Greenpeace, World Wide Fund for Nature (WWF)
Intergovernmental Organizations (IGOs)
Established by international agreements
EX: United Nations Environment Programme (UNEP), United Nations Educational, Scientific, and Cultural Organization (UNESCO), International Union for the Conservation of Nature (IUCN)
Governmental Organizations (GOs)
Restricted by national politics, but brings internatal conventions and laws into force
EX: National Departments of the Environment
