Intro to Ecology
Study of how organisms INTERACT
with each other and their environment
TEKS 8.6 (C)
Describe interactions within
ecosystems.
Life Levels and Organization
Biosphere
The biosphere is the
outermost part of the
planet’s shell —
including air, land,
suface rocks, and water
— within which life
occurs, and which
biotic processes in turn
alter or transform.
Biome
a biome is a major regional group of
distinctive plant and animal communities
best adapted to the region's physical natural
environment, latitude, elevation, and
terrain.
Examples of biomes include the desert, rain
forest, artic tundra, grassland, coniferous
forest, decidious forest, and oceans.
Ecosystems
All the biotic (living) and abiotic
(nonliving) factors that will INTERACT
with each other in some subset of the
biosphere.
Abiotic factors: soil, water, temperature,
elevation, and location on the earth.
Coral Reef Ecosystems
Yellowstone National Park
Ecosystem
Community
Groups of many different species of
organisms interacting in a particular area
(predator prey relationships)
Only the biotic factors that interact
between different species of organisms
Population
A group of organisms of ONE species that
interbreed and live in the same place at the
same time. A population of aliens
A Population of Aliens
Producer (autotroph)
Producers (autotrophs)
are always at the base
of the chain. Producers
are organisms that
make their own food.
Plants are producers.
Herbivore
Herbivores are
animals that
only eat plants.
A cow and a
deer are
herbivores.
Omnivore
An omnivore
eats both plants
and animals.
Humans and
bears are
omnivores.
Carnivore
Animals that eat
meat are
carnivores. A lion
and a wolf are
carnivores.
Decomposer
A decomposer eats dead or dying
organisms.
Producers and Consumers
So…producers make their own
food (e.g., photosynthesis) and
consumers don’t.
Is a dog a producer or a
consumer?
Is a termite a producer or a
consumer?
Food Chain
The simplest
feeding
arrangement in
an ecosystem.
Food Chain
A food chain is the flow of energy
from one organism to the next.
Describe the Food Chain
Describe the Food Chain
Describe the Food Chain
Energy Flow
Sun major supplier of the earth’s
energy.
Most of the energy released is
lost in the form of heat.
The Flow of Energy
Producers - Plants capture the sun’s energy and
store it in food
Primary Consumers (herbivores) - Animals that
receive their energy directly from plants
Secondary Consumers (carnivores) - Consumers
that feed on primary consumers
Energy flows from the sun to the producer, then to
the primary consumer, then to the secondary
consumer, third level consumers, forth level
consumers, etc...
Pyramid of Numbers
Carnivore populations are
smaller in comparison to
the rest of the ecosystem.
They require more food to
sustain their lives than the
lower organisms.
The amount of useable
energy that is transferred
from trophic level to
trophic level only 10%.
Let’s Practice
How many trophic levels
are present?
5
Determine the amount of
useable energy for the
different trophic levels.
Level 2: 35 J
Level 3: 3.5 J
Level 4: 0.35 J
Level 5: 0.035 J
Food Webs
Many food chains
interacting with each
other.
The arrow always points
away from the organism
being eaten to the
organism doing the eating.
Shows the movement of
energy and matter in an
ecosystem.