Ecology
…the study of how organisms interact
with each other and their environments

Ecology- scientific study
of interactions between
organisms and their
environment.
How Everything Fits Together

How are this bee, the flowers,
and the sun interacting?
The study of
how the living
and nonliving
things fit
together in
nature is the
science of
ecology
Like a set of nesting dolls…


We can think about the
interactions and types of living
things by organizing them into
groups, smallest to largest.
A species (individual) includes
only one type of organism.


Example: pigeon
A population includes all
members of one species that
live in the same area.

Example: all the pigeons in
Denton
…bigger and bigger groups!

A community includes all of the
different species that live in the same
area.


Example: all the pigeons, ants, maple
trees, dogs, etc. that live in Denton
An ecosystem includes both the
community and the abiotic factors.

Example: the Denton community plus the
cars, buildings, rocks, air…
Levels of Organization
Levels of Organization

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Individual
Population
Community
Ecosystem
Biome
Biosphere
Make a sentence using the first letters of each level to
remember the order!
The organisms in a habitat can be
organized in the following way…
ecosystem
Species/
organism
population
community
Ecosystem


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Groups of animals live in specific
habitats.
There are two factors included in
every habitat:
Biotic factors


Living things, like…?
Abiotic factors

Nonliving things, like…?
Abiotic Vs. Biotic Factors
Abiotic Factors
 The nonliving
environment
 Ex.: air currents,
temperature, light,
moisture, and soil
 Determine which
species survive in a
particular
environment
Biotic Factors
 The living organisms
that inhabit an
environment
 Ecologists study
how biotic factors
affect different
species
Habitat vs. Niche

Each species occupies a particular position within
the community, both in a spatial sense (where it
lives, referred to as its habitat) and a functional
sense (how it lives, its niche).

A number of species may occupy a particular
habitat but the niches of those species differ to
avoid competition.
Habitats


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A habitat is the place where an
organism lives out its life
Organisms use a variety of different
strategies to live and reproduce in
their habitats
Habitats can change or disappear
from an area through both natural
and human causes
Niches

How an
organism
meets its needs
for food and
shelter, how it
survives, and
how it
reproduces
Niches


What niche does this
lizard occupy?

A species niche includes
all of its interactions
with the biotic and
abiotic parts of its
habitat
It is an advantage to
have a unique niche in
an environment
This reduces
competition
Niches

In the coastal habitat in Florida there are a number of species of
wading birds, each with a unique niche
Niches

These species differ in their
beak depth. Beak depth
corresponds to the size of
seed the bird eats.

On two islands, only one of
these species is found. Note
that there is a difference in
beak depth when the species
is alone compared to when it
is with the other two
species. In the presence of
these other species, beak
depth differences have
evolved that reduce
competition.
Biomes
Biome
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Major communities that occur over
wide areas on land
Scientists have divided the Earth into 79 major biomes
Climate – temperature and
precipitation.
Climate dictates biomes.
Major Biomes of the Earth
Biomes
Terrestrial
Tropical rainforest
Temperate rainforest
Temperate deciduous forest
Tiaga (boreal forest)
Tundra
Desert
Temperate grassland
Savannah
Chaparral/Steppe
Urban
Marine
Open ocean
Antarctic ocean (edge of the ice)
Estuary
Coral Reef
Barrier Island
Shallow ocean/bay
Mangrove forests
Freshwater
River
Lake
Pond
Wetlands (Swamps, marshes, etc.)
Taiga
Tiaga (Boreal Forest)
Animals of the Taiga

Rodents, snowshoe hares, lynx,
caribou, bears, wolves, birds in
summer
Deciduous Forest

A forest biome with many
kinds of trees that lose
their leaves each autumn
Temperate Deciduous Forest
Animals of the Deciduous
Forest

Wolves, deer, bears, and a
wide variety of small
mammals, birds, amphibians,
reptiles, and insects
Tropical Rain Forest

A hot, humid biome near the
equator, with much rainfall
and a wide variety of life
equator
Tropical Rainforest
Animals of the Tropical
Rain Forest

More species of insects, reptiles, and
amphibians than any place else;
monkeys, other small and large
mammals, including in some places
elephants, all sorts of colorful birds
Desert

A sandy or rocky biome, with
little precipitation and little
plant life
Desert
Animals of the Desert

Rodents, snakes, lizards, tortoises,
insects, and some birds. The Sahara
Desert in Africa is home to camels,
gazelles, antelopes, small foxes,
snakes, lizards, and gerbils
Tundra

A cold biome of the far north;
the ground is frozen even in
summer
Animals of the Tundra

Musk oxen, migrating caribou, arctic
foxes, weasels, snowshoe hares, owls,
hawks, various rodents, occasional
polar bear.
Arctic Fox
Grassland

A biome where grasses, not
trees, are the main plant life.
Prairies are one kind of
grassland region.
Grassland animals

American Grasslands: Prairie
dogs, foxes, small mammals,
snakes, insects, various birds
Marine Biomes
Open Ocean
Coral Reefs - Barrier Islands - Shallow Marine…
Temperate Desert
Forest
Name
Tundra
Grasslands
the
Biome
Tropical
Tiaga
Rainforest