Transcript Community - Londonderry NH School District

U11: Community
Species in a Particular Area
• A species is a group of the same organisms that are
able to reproduce naturally produce fertile offspring.
A mule is not a species because it is an offspring from
a male donkey and a female horse. Organisms of a
particular species, living in a given geographic area are
called a population. A community is a collection of
populations of different species, interacting with one
another.
• List three populations in the Londonderry community
________________________________________
Horse, Donkey & Mule
One of these is not like the others!
Populations make up a
Community
• No individual organism lives completely on its
own. It may live with other individuals of the
same species to form a population.
Populations make
up a Community
• If you counted all the daisies in a field they
would make up the daisy population of that
field. You might also find populations of
spiders, earthworms, or field mice. A change
in the size of one population often causes a
change in the size of another population.
• Populations can be counted in many different
ways such as ear tags, leg bands, radio
transmitters, and physical counts. Populations
are not spread out evenly for example the
human population is clumped larger in cities.
A clumped population can be useful as they
can help one another find food or shelter
Elephant seal
• Many species of animals live in groups for
protection. Some groups are called herds,
flocks, or packs. Plants living in clumps can
help each other too, for example trees
clumped together protect each other from
strong winds.
List a population that lives in a group for
protection from predators ______________
(not one in this presentation)
Starlings
The levels of organization
So far we discussed that a particular
species make up a population and
populations make up a community. How
are the other levels organized? An
interacting system that consists of
groups of organisms (biotic) and their
abiotic environment is an ecosystem. List
an ecosystem in NH
________________________
Ecosystems make up biomes. Southern
NH is in the deciduous forest biome,
Arizona is in the desert biome, and Alaska
is in the tundra biome.
NH
Biome- a large geographical area with a similar climate.
Biomes make up Earth’s biosphere.
Biosphere – all
the biomes with
all the living
things on Earth
• List the levels of organization from
smallest to largest. (biome, biosphere,
community, ecosystem, population, species)
_____________--> _____________-->
_____________-->_____________-->
_____________--> ____________
Levels of Organization
Individual = species
Every Organism Has a Job
• Every organism has a role or job in a
community. All of an organism’s activities or
jobs within its ecosystem are called a niche.
• All organisms in a community are related to
each other through their niches.
Niche
• What is your niche at your home? Here are some
questions to consider when you interact with
your environment. What do you eat? What jobs
do you do? When do you wake or go to sleep?
The answers to these questions describe your
own specific niche.
• What is your niche?
_____________________________________
• If your parents left town for 2 weeks how would
your niche change while they were away?
__________________________________________
Producer Niche
• Producers: The niche of green plants is to
produce food from sunlight, water and carbon
dioxide during photosynthesis.
Consumer Niche
• Consumers: The niche of the mouse is to
consume the plants and to be food energy or
prey for predators. A bee’s niche is to
pollinate flowers when they collect nectar to
make honey.
Decomposer Niche
• Decomposers: The niche of the earthworm is
to help decompose the organic matter in the
soil into nutrients. The earthworm brings
these nutrients to different locations and
moves increasing water and air flow so that
plants roots can get water and nutrients.
• The populations of daisies, mice, bees, spiders
and earthworms in the field make up a
community. A community is a collection of
populations of different species, interacting
with one another.
• The different populations in a community
depend on each other. How can this be true?
Depend on Each Other
• The daisies in the field can provide shelter for
the spiders. The mice can eat the seeds of the
daisy. The earthworm feeds on the decaying
matter in the soil.
• How do mice and earthworms help the daisies?
• All organisms in a community are related to each
other through their niches.
List two examples of niches in a community.
1.
2.
Niches Change with Competition
• Why don’t populations increase forever? Any
condition that keeps the size of a population
from increasing is a limiting factor. Lack of
light, space, water, oxygen, nutrients or food
are all examples of limiting factors.
Friends of Nairobi National Park, Kenya -
6x a yr
Niches Change with Competition
• Some organisms may not get enough of these
materials. The lack of needed materials causes
population growth to slow down by
decreasing the number of births and
increasing the number of deaths. Moving in
(immigrate) or out (emigrate) of an area also
increases or decreases the population of an
animal. Competition prevents organisms from
occupying all of their niche.
Niches Change with Competition
• The struggle among organisms to get their
needs for life is called competition. As a
population increases in size the competition
for the same resources (food, sunlight, etc)
increases.
Every Organism Has a Home
The address or home of an organism is their
habitat. The worm and the spider may use a
hollow log and the surrounding area as its
habitat while our skin is the habitat for millions
of bacteria that live there.
• What is your habitat?
_____________________________________
Habitat
• The habitat for some species of bacteria is on the
outside as well as in the inside of our bodies
(skin, eyes, nose, stomach, intestines, mouth…)
• The bacteria cells in or on our body
outnumber human cells 10 to 1,
because they are much smaller
than human cells, they account
for only about 1 to 2 % of our body mass
though they do make up about half of our body’s
waste!
• How many cells does a human have? 100 trillion?
Bacteria on YOU!
Vocabulary
Light (exposure to light can change climate & growth of plants)
Heat (will determine the weather/climate of an ecosystem)
Mechanical Support (any features (i.e waterfalls, valleys, hills) which
can either facilitate or inhibit a species survival
Organic Matter (this will determine soil nutrition and therefore plant
growth)
Nutrients (Oxygen, Nitrogen, Carbon, Phosphorous etc.) are essential
stability of an ecosystem
Water/ Air (Water and Air quality will play a drastic role in the
survivable of a species; streams, rainfall etc.)
Predation (Predators will limit the growth of the population as well as
human pouching)
Competition (Competition within the species and with other species
for food, water, mates will limit further growth)
Geographical Space (If the species can only survive within a given
ecosystem, the size of that ecosystem will prevent further population
increases)
Questions
• 1. The barnacle species Chthamalus can
survive in shallow and deep water. The
barnacle species Balanus can live only in deep
water. When Chthamalus and Balanus live in
the same habitat how would the niche of
Chthamalus change due to competition?
_______________________________________
_______________________________________
• 2. What would happen to Chthamalus if
Balanus moved away from this habitat?
_______________________________________
_______________________________________
• 3. What is the limiting factor for the barnacles
in this habitat? _________________
4. How can limiting factors cause a
population to change?
__________________________________________
__________________________________________
5. Explain why it is easier to count plant
populations rather than animal populations in a
community?
__________________________________________
__________________________________________
6. List abiotic and biotic factors in a forest ecosystem.
____________________________________________
____________________________________________
Ecosystem - An interacting system that consists of groups of
organisms (biotic) and their abiotic environment.