Unit 1BIntro to
Ecology
The Biosphere:
• all life on Earth and all the parts of
the Earth where life exists
• Ecology is the study of the
interactions of all of the organisms
and their environments in the
biosphere
Levels of Organization in
the Biosphere
1. Organism- one individual of a certain
species
2. Population- group of individuals of the
same species living in the same area
3. Community- different populations living
together in the same area
4. Ecosystem- all the organisms in a certain
place together with their physical
environment
5. Biome- a group of ecosystems with similar
climates and typical organisms
6. The Biosphere- all living things from all
biomes on the planet
• Where is the biosphere located and what does it
include?
o The biosphere is everywhere on our planet where there is
life. This can be far above the land where birds fly, deep
into the oceans where sea creatures live, or even deep
underground where extreme bacteria can inhabit vents
and volcanoes. It includes all the living things and the
abiotic features of the planet that they interact with and
rely upon.
o Because there is life nearly everywhere on Earth, the word
biosphere is a very broad term and the Earth itself is
essentially our biosphere.
Fill in each box with the correct level of organization in the biosphere (the size of the box indicates the broadness of each category).
Include a word or two to help you remember what each grouping means.
__________________-
________________-
________________-
________________-
__________________Population-
Levels of
Organization in
the Biosphere
_____________________-
Environments:
• The conditions or
factors surrounding
an organism
• Consist of biotic
and abiotic factors
Biotic Factors
• Any living part of the environment
• Includes animals, plants, fungi,
bacteria, etc.
Abiotic Factors
• Any nonliving (physical) part of the
environment
• Examples: sunlight, heat, precipitation,
humidity, wind, water, soil, etc.
What are the Biotic and Abiotic
Factors in this Environment?
Biotic and Abiotic Factors are
Closely Linked
The mucky
shoreline,
biotic, abiotic
or both?
Both!
Abiotic- soil, water,
sand, etc.
Biotic- bacteria,
fungi, small
animals like worms,
etc.
Energy,
Producers,
and
Consumers
Energy
• Organisms must get energy in order to
function
• Different organisms get their energy in
different ways
• Almost all energy on Earth starts from
the sun!
1. Autotrophs
• Organisms that capture energy from
sunlight or chemicals and turn it into
food
• Also called primary producers
Primary Producers
• Most commonly use energy from the sun to
create sugars and starches (photosynthesis)
• Important examples: plants, algae,
photosynthetic bacteria
Chemosynthesis
• When primary producers turn the
energy in chemicals (like hydrogen
sulfide) into carbohydrates.
o Mostly bacteria
o Found in extreme environments (deep ocean, hot springs,
volcanoes)
2. Heterotrophs
• Eat other organisms for food.
• Also called consumers
Types of Consumers
* Put these
definitions in the
correct bubbles on
pg. 6 in the notes.
Classified by the way they acquire energy
• Carnivores- kill and eat other animals
• Herbivores- eat plant materials
• Omnivores- eat both plant and animal
materials
• Scavengers- consume carcasses of
organisms that have died or that were killed
by predators
• Decomposers- feed by chemically breaking
down organic matter into detritus, debris
from decomposing plants and animals (Ex:
fungi and bacteria)
• Detritivores- feed on detritus particles (Ex:
earthworms)
Types of
Consumers
Food
Chains
and Food
Webs
Energy Flows One Way
• Almost all energy on Earth starts from the
sun!
• Energy flows through an ecosystem in a one
way direction from producers to consumers
• Food Chain- a series of steps in
which organisms transfer chemical
energy by eating and being
eaten.
(food molecules are chemicals)
Phytoplankton =
algae that is floating
and not attached to
something
**Read an arrow as “is eaten by”
Food Webs
• Food web- a
network of complex
interactions formed
by the feeding
relationships among
the organisms of an
ecosystem
Algae
Plants
Decomposers and Detritivores
are Important in Food Webs
• Dead plant and animal material must be
broken down so the molecules can be reused
for new life
• Decomposers (bacteria and fungi) are
heterotrophs that break down this dead plant
and animal material into detritus
o This releases nutrients into the soil for new
primary producers to grow (“recycles
nutrients”)
• Detritus is eaten by detritivores (like crayfish,
grass shrimp, and worms), further releasing
nutrients into the soil
Food Web Disturbances
• Environmental
changes can cause
changes in a food
web
Krill
Food Web Disturbances
• How would a decrease in the krill population affect
the Antarctic food web?
• What do ecologists mean when they say that killer
whales indirectly depend on krill for survival?
Trophic Levels
• Each step of a food
chain or food web is
called a trophic level
• First trophic levelalways primary
producers
• All other trophic levels
are occupied by
different types of
consumers
Ecological Pyramids
• Illustrations used to
show the amounts
of energy or matter
in each trophic
level of a food web
• Three types of
pyramids: energy,
biomass, and
numbers
Pyramids of Energy
• Show the amount of
energy available at
each trophic level
• Only 10% of the energy
in one trophic level is
passed to the next level
up.
• The rest of the energy is
either used by the
organisms to do life
processes (like growth,
reproduction,
respiration, etc.), or
released as heat
How much of the energy available to
the producers is available to the
third-level consumers?
Pyramids of Biomass
• Biomass is the total amount of living tissue in a
trophic level
• Primary Producers will have the greatest
biomass
o There must be enough producers to provide energy
for all of the consumers
Pyramids of Numbers
• Show the number of
individuals at each trophic
level
• If the main producer is a
large organism, the base
of the numbers pyramid
will be small
Pyramid of Numbers
Grass
Pyramid of Numbers
Niches and
Community
Interactions
Tolerance:
The ability to survive and reproduce under a variety of
environmental circumstances.
Outside the optimum range causes stress (struggling
to maintain homeostasis).
For any environmental factor, going beyond the upper
or lower limit can lead to death.
Habitat
• The general place where an organism
lives
• Organisms will live where they can
tolerate (or handle) the conditions
Niche
• What an organism does in its
habitat, how it interacts with its
environment, and how it
contributes to an ecosystem
• Example:
“The red fox's habitat might include forest edges, meadows and the
bank of a river. The niche of the red fox is that of a predator which
feeds on the small mammals, amphibians, insects, and fruit found in
this habitat. Red foxes are active at night. They provide blood for
blackflies and mosquitoes, and are host to numerous diseases. The
scraps left behind after a fox's meal provide food for many small
scavengers and decomposers.”
• Make a list of things in your niche
Competition
• When organisms
attempt to use the
same resource,
competition
occurs
o Example: the roots of
different plants compete
for water, nutrients, and
space in the soil
Types of Competition
• Intraspecific- competition
between members of the same
species
• Interspecific- competition
between members of different
species.
The Competitive Exclusion Principle:
• The idea that no two species can
occupy exactly the same niche, in the
same habitat, at the same time
• If two species try to do this, one of
three things can happen:
o 1 species will compete better for the niche and the other
species will die out
o 1 species will compete better for the niche and the other
species will move away
o The two species will split or share the niche. Ex: rainforest
lizards that eat the same bugs can occupy different parts
of the forest
What Is a Biome?
• Large regions of land that are characterized
by a specific type of climate and certain
types of plant and animal communities.
• Made up of many individual ecosystems
• Vary according to their location from the
equator (latitude)
Biomes of the World
In which biome is Livingston, NJ located?
“Temperate forest”, also called “temperate deciduous forest”
Phytoplankton =
algae that is floating
and not attached to
something
**Read an arrow as “is eaten by”
Algae
Plants