Transcript Unit 11 – Organization of Life

Unit 11 – Organization of Life
Ecology – study of the interactions
between organisms and their
environment
Ecosystem Structure
• Biosphere – part of the Earth in which life exists
including land, water, air and atmosphere
– Ecosystem – different communities and their nonliving environment
• Community – different populations living in the same area
– Population – many members of 1 species living in the same area
» Species – group of similar organisms that can breed and
produce fertile offspring
» Organism – 1 member of a species
• Which is the biggest or broadest?
• Which is the smallest or most specific?
Species, Population, Community,
Ecosystem, Biosphere?
Species, Population, Community,
Ecosystem, Biosphere?
Species, Population, Community,
Ecosystem, Biosphere?
Species, Population, Community,
Ecosystem, Biosphere?
Factors in Ecosystems
• Ecosystems are influenced by biological and
physical factors.
• Biotic Factors (Biological)
– Living organisms that influence an ecosystem
– Ex Predator and Prey
• Abiotic Factors (Physical)
– Non-living factors that influence an ecosystem
– Ex Soil, Water, Temperature, Sunlight
What is an ecosystem composed of?
Mountain,
clouds, water &
rocks
Non-Living ONLY
Abiotic Factors
Biotic Factors
Living ONLY
Trees, bird, grass,
rabbit, & moose
ECOSYSTEM
Living & Non-Living
Together
Roles in Ecosystems
• Niche – an organisms role in its ecosystem - full
range of physical and biological conditions in
which an organism lives and the way in which the
organism uses those conditions
– If an organism dies, another organism will take over its
niche
– Your niche right now is being a student
• Habitat – the environment in which an organism
lives
– Your habitat is your house
Relationships - SYMBIOSIS
• Symbiosis – organisms that live together
– 3 types
• Mutualism – both organisms benefit
– Ex bee and flower
• Commensalism – one organism benefits and the other
is not hurt
– Ex bird nest in a tree
• Parasitism – one organism benefits and the other is
harmed
– Mistletoe growing on a tree
Parasite Example
Cuckoo Egg!
The cuckoo lays eggs in
other species of bird’s
nests. It hatches first and
pushes out the other bird’s
eggs. Then the mother bird
raises the cuckoo rather
than her own babies!
Land Biomes
Biome = large group of ecosystems
that share the same climate and have
similar types of communities
What determines the different types of
biomes?
• Latitude –
distance of any
point on the
surface of the
Earth north or
south from the
Equator
– Impacts weather
and climate
Climate vs. Weather
• Climate – average weather conditions in an
area including temperature and precipitation
• Weather – condition of the atmosphere at a
specific place and time
– We listen to the weather report everyday on the
news
Why we have different seasons and
different biomes
Different Land Biomes
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Tundra
Boreal Forest
Temperate Foreest
Temperate Woodlands/ Shrubland
Temperate Grasslands
Desert
Tropical Savanna
Tropical Seasonal Forest
Tropical Rain Forest
Tundra
• Just below the polar
ice caps
• No trees
– Soil only thaws a
couple of cm during
the spring/ summer,
so it is impossible for
tree roots to grow
• Permanent layer of
frozen soil
– Called PERMAFROST
Boreal Forest
• South of the tundra
• Evergreen forest
• Also called Coniferous
Forest or Taiga
Temperate Forest
• Directly south of the
Boreal Forest
• Covers most of southern
Canada, the eastern US,
most of Europe, Asia and
Australia
– We live in this biome
• Composed mostly of
DECIDUOUS trees
– Trees that lose their leaves
in the fall
Temperate Woodland/ Shrubland
• Also called the Chaparral
• Open woodlands (trees) and shrubs (small
plants that have woody stems)
Temperate Grassland
• Also called the prairie, pampas, savannah
• Drought, grazing animals and fires keep the
grassland from becoming forests
• Fertile soil
Desert
• Exist on every continent except for Europe
• Any area in which the rate of evaporation is
greater than the rate of precipitation
– Very little precipitation
• Coldest Desert – Polar Ice Caps
Tropical Savanna
• Grasses, scattered trees, get less precipitation
than other tropical areas
• Africa, South America, Australia
Tropical Seasonal Forest
• Has a dry season and a rainy season
• During the dry season, the trees drop all of
their leaves
• Like the jungle
Tropical Rain Forest
• Warm temperatures,
large amounts of rainfall
throughout the year
• Found in Central and
South America, Africa,
Asia, Australia
• Most diverse of all
biomes
Aquatic Biomes
Aquatic Biomes
• Two Types – Marine (Salt) and Freshwater
• Cover more than 75% of the biosphere
– 97% of water on earth is salt water
– 3% of water on earth is fresh water
Freshwater Biomes
• Ponds and lakes
• Rivers and streams
• Wetlands
Ponds and Lakes
• If they don’t have a connecting river, they
were formed by glaciers.
• Life: Plankton, Algae, Insects, Fish,
Crustaceans (crawfish), floating aquatic plants
• Climate can vary depending on Geographic
location
Rivers and Streams
• Bodies of flowing water, moving in one
direction
Wetlands
• Areas of standing water that support aquatic
plants
• Also called Marshes, Swamps, Bogs
Marine Biomes
• Coral Reefs
• Oceans
• Estuaries
Coral Reefs
• Warm, shallow waters
• Usually barriers around continents or islands
• Very many different species of plants and
animals
Oceans
• Largest biome of the world
Estuaries
• Where freshwater streams or rivers meet the
ocean
– Higher salt concentration than freshwater, but less
than marine biomes
Population Ecology
Population Characteristics
1) Population Density
2) Spatial Distribution
3) Population Range
Population Characteristics • Population Density is
the number of
organisms per unit of
area
Population Characteristics
• Spatial Distribution – also called Dispersion –
pattern of spacing of a population within an
area
– Uniform – black bears are spaced out pretty
evenly
– Clumped – animals found in herds - cattle
– Random – deer – found clumped and uniform –
no predictable pattern
Population Characteristics
• Population Ranges – can be affected by
temperature, humidity, rainfall, or sunlight.
Also can be affected by predators,
competition, parasites, threats to survival
– Abiotic Factors
– Biotic Factors
Things that Effect a Population
1. Predation
- Predators: as the number of prey increase, the number of predators will too
2. Disease
-
Outbreaks occurs when population density is high
Disease is transmitted easier
3. Parasites
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Similar to disease, when population density
is high, parasites are
transmitted easier
4. Competition
- Individuals compete for:
Food, water, shelter, & space
Population Limiting Factors
•Two Types
•Density-Independent
•Abiotic Factors
•Density-Dependent
•Biotic Factors
Density-Independent Factors
• Any factor in the environment that does not
depend on the number of members in a
population.
– Usually abiotic – weather events
Before
After
Density-Dependent Factors
• Any factor in the environment that depends
on the number of members in a population
– Usually biotic factors – predation, disease,
parasites, competition
Predation – what happened to the moose
population as the wolf population
increased?
Disease – when the density of a
population is too high, diseases are
transmitted more easily than a lowdensity population
Competition – Competition increases
when density increases
Parasites – populations can be limited
by parasites
Population Growth Rate
Growth Rate, Emigration, Immigration,
Exponential Growth, Logistic Growth,
Carrying Capacity
Population Growth Rate
• Definition – explains how a population grows
• Formula to calculate growth rate
Births – Deaths = Growth Rate
Time
Factors Effecting Growth Rate of a
Population
• Natality – number of births
• Mortality – number of deaths
•Emigration – leaving or exiting a
population
•Immigration – moving into a population
Types of Growth in a Population
• Logistic – population level balances out
– Births < deaths and/ or…
– Emigration > immigration
Types of Growth in a Population
• Exponential
– Births > Deaths and/
or…
– Emigration <
Immigration
Carrying Capacity
• Definition – Maximum number of individuals in a
species that an environment can support for the
long term.
Carrying Capacity
What type of growth is this?
Human Population Growth Rate