Download Biodiversity

Biodiversity
Learning Target
BIODIVERSITY
 What is biodiversity?
 The variety of life on earth
 Focus of Biodiversity
1. Different species of plants & animals
2. Diversity of genes (genetics)
3. Different ecosystems on the planet
BIODIVERSITY
 Why is biodiversity important?
1. Ecosystem survival
2. Human society
3. Continue evolution
1. Ecosystem Survival
 Which is more diverse?
 Which is more stable?
1. Ecosystem Survival
 Why is biodiversity important to
ecosystems?
 Strengthens the food web!!
 Resist disturbances
 Rebound from natural disasters & human
interactions
2. Human Society
 We are the smartest species on Earth
 But we are the most dependent!
 How does biodiversity help human society?






Food – ex: bacteria help our food grow
Economy - $$
Medicines – plants & bacteria
Wood products
Pollution break down
Research
3. Continued Evolution
 Why do things evolve?
So they can survive & adapt!
The rate of evolution has slowed dramatically
The amount of biodiversity has decreased
Without biodiversity, many more animals will go
extinct
 Diversity helps organisms evolve to fight disease &
survive in their surroundings




SPECIES EXTINCTION
Threatened = Species that are still abundant in their
natural range, but are declining in numbers and are
likely to become endangered
Examples in Pennsylvania: Osprey, Sedge Wren, Yellowbellied Flycatcher
SPECIES EXTINCTION
Endangered = Species that have few individual
survivors and therefore could soon become extinct
over most or all of the species’ natural range
Examples from Pennsylvania: Bald Eagle, Short-eared
Owl
SPECIES EXTINCTION
Extinct = Species that have completely disappeared
from the Earth.
Example from Pennsylvania: Passenger Pigeon
Species
Extinction
Extinct – Giant Short
Face Bear
Endgangered Orangutan
Threatened – King
Cobra
SPECIES EXTINCTION and
DESTRUCTION OF BIODIVERSITY
1. Human Population Growth
A. 1000 B.C. = 50 million people
B. 2012 = 7 BILLION people
C. The more our population grows
1) Need more resources
2) Produce more pollution
2. Resource Use
A. Natural resources = anything in the environment used by
people
B. Renewable (trees, sunlight) & nonrenewable (coal, oil)
SPECIES EXTINCTION and
DESTRUCTION OF BIODIVERSITY
3. Pollution
A. Soil < Water < Air
1)
2)
3)
4)
5)
Chemicals
Waste
Noise
Heat
Light
SPECIES EXTINCTION and
DESTRUCTION OF BIODIVERSITY
4. Habitat Destruction
A. Deforestation – cutting down the forest
B. Habitat fragmentation – ex: building a highway or
road through a forest
C. Plowing Grasslands
5. Poaching – illegal hunting or removal of wildlife
6. Overfishing
SPECIES EXTINCTION and
DESTRUCTION OF BIODIVERSITY
7. Native vs. Exotic/Invasive Species
A. Species that is introduced by
humans and is not native to that
habitat
B. Introduction by accident or on
purpose
C. Throws off ecosystem & food web
1) How does this happen?
2) Take over habitat, food sources, no
natural predators
D. Ex: Kudzu vine
LIMITING FACTORS
 Limiting factors = environmental
factor that causes a population to
decrease
1. Food & water
Example: A giraffe needs 10
kilograms of leaves a day. The
trees can only produce 100
kilograms of leaves
What is the carrying capacity?
LIMITING FACTORS
2. Space
A. Nesting space
B. Territory
C. Trees need enough room to get light, nutrients, etc
3. Weather
A. Temperature
B. Rainfall
How can we protect
biodiversity?
1. Captive breeding
A. Mating animals in zoos, etc.
B. Release into the wild
2. Laws & treaties
A. Endangered Species Act – protects endangered species
from hunting & trade
B. CITES – international treaty - not mandatory!
3. Habitat preservation
A. 1872 – Yellowstone National Park
B. 7,000 preservation parks today
Symbiosis
 Mutualism – both species benefit (+/+)
 Parasitism – parasite feeds off the host (+/-)
 Commensalism – one species benefits and the
other is neither helped nor harmed (+/o)
 Predation – one species eats another (+/-)
 Competition – one species is the better
competitor (+/-)
Species Interactions from
Nature – PBS