Download Slide 1

BIODIVERSITY / CONSERVATION
Biodiversity
Variety of life on planet Earth
• Includes the genetic, species, and ecosystem diversity
• About 1.7 – 2 million organisms currently known
• Estimated that there are 3 – 100 million total on Earth
WHY DO ESTIMATES VARY SO MUCH?
Levels of Biodiversity
• Species Diversity- number of species
in an area
• Ecosystem Diversity- number of
ecosystems or habitats in an area
• Genetic Diversity- Different genes or
Traits available in a population
Benefits for all species
• Species depend on each other for
survival
• Keystone species- critical
species that affects the survival of
other species
• Foundation species- primary
producer within an ecosystem
which if eliminated, it will collapse
the system
Benefits of Biodiversity
• Ecosystem: Loss of biodiversity at
any level could lead to ecosystem
instability (ex: keystone species)
• Agriculture: pest resistance,
commercial uses (ex: babassu palm,
gives more oil than coconut and could
be used for cooking, etc.)
• Medicine: cures for diseases (ex:
rosy periwinkle used to treat
Hodgkin’s lymphoma) – 25% of
prescriptions come from plants
• Ecotourism: source of income for
many countries (ex: Costa Rica)
Loss of Biodiversity
• Organisms naturally go extinct if they cannot survive
• Times when extinction rate is much greater (mass
extinctions)
• Currently we could be in the “Sixth Mass Extinction”
Loss of Biodiversity
• Background extinction- Extinction through
natural process.
– Usually a very small number per year
• Mass extinction- abrupt rise in extinction rates
– Usually global
– 25-70% species loss
– 5 mass extinctions have occurred over 500 million
years
– Adaptive radiations- post mass extinction where
diversity increases
• Adaptive radiations- post mass extinction
where diversity increases
Loss of Biodiversity
• ENDANGERED SPECIES  Serious risk of
extinction
• THREATENED SPECIES  Likely to become
extinct soon
•ENDANGERED SPECIES - A species is likely to
become extinct if not protected
Loss of Biodiversity
• Extirpated- species that have disappeared
from an area where they once lived, but still
exist elsewhere
• Extinct- A species that once occurred but no
longer exists across their original range
PA Endangered Species
BOG TURTLE  Draining or
destruction of its habitat are
causing it to go extinct… (very
rare so worth money and illegally
removed at times)
MASSASAUGA RATTLESNAKE 
Only found in historic sites due to
dam building, highway construction,
urbanization, forest succession,
mining, and agricultural activity
Causes of Biodiversity Loss
1) Habitat Fragmentation: Division of habitat into smaller
patches (ex: clearing forests, building roads, etc.) 75% of
all extinction is caused by habitat loss
2) Invasive Species: Exotic species move in and spread
(ex: Zebra mussel)
• Exotic species- species introduced to an area that
are not native
3) Pollution: Harmful chemicals find their way into
habitats (ex: metals, oils, fertilizers)
Habitat Fragmentation
Causes of Biodiversity Loss
4) Overharvesting: Catching / hunting too much (ex:
Siberian tiger)
-POACHING  Illegal capture or killing of an
organism for $$$
5) Climate Change: Warming temperatures on Earth
Critical Areas of Biodiversity
• HOTSPOTS- areas of the world that are
being destroyed rapidly
– 34 identified spots worldwide
– Endemic Species- species that are native,
and only found in that localized area
Critical Areas of Biodiversity
– Tropical Rain forests- 7% of worlds area,
50% of earth’s species
Critical Areas of Biodiversity
• Coral Reefs- high biodiversity, major damage
is from ecotourism
• worth $375 Billion
Protecting Biodiversity
• Protect biodiversity “hotspots” (lots of organisms)
-ENDEMIC SPECIES: found only in one area
Madagascar Lemurs
Galapagos Tortoise
• Economic approaches (ex: get paid to conserve)
Protecting Biodiversity
• Endangered Species Act  1973 - Law that protects
biodiversity
-Successful with Brown Pelican and Bald Eagle
-Costs can be high (ex: Spotted Owl protection caused many
loggers to lose their jobs)
• Captive Breeding  Process of breeding and raising organisms
in controlled conditions (ex: Zoos)
• Convention on International Trade in Endangered Species of
Wild Fauna and Flora (CITES)  Treaty to save biodiversity
(bans transport of their body parts)
Legal Protection
• Private groups- most successful- Green Peace, WWF,
and Conservation International
• International Union for the Conservation of Nature
and Natural Resources- provides a global list of
endangered and threatened species (Red List). Also
controls and enforces illegal trade of poached animals
or parts.