Download Unit 2 Lesson 1 Overview of Ecology

Springfield Central High School
1. Explain what ecology is.
2. In the relationship between the lynx and the hare,
what factors, biotic and abiotic, can cause these two
populations to rise and fall?
3. Explain the levels of organization in ecology using
the example of a zebra.
4. Describe the feeding relationships in ecology.
What do you think
ecology is?
Ecology: n. branch of biology
dealing with the relationships
between organisms and the
environments.
Ecology shows relationships
among living (biotic) and
nonliving (abiotic) parts of
the world.
Concepts to Be Discussed in
Unit 2 Ecology:
Interaction
Interdependence
Evolution
Cycles
What is Ecology?
The word ecology has a Greek origin;
"oikos" in Greek means "house", while
"ology" means "discussion" or "study".
1. What does the term “Eco-Friendly mean?
2. Give me four examples of things you consider “EcoFriendly items or processes.
3. What is Ecology? How does it involve us?
Activity: Make a Food chain involving at least 5
organisms of your choice. Draw it out showing what
eats what.
Central Concept: Ecology is the interaction among organisms and between
organisms and their environment.
6.1 Explain how birth, death, immigration, and emigration influence
population size.
6.2 Analyze changes in population size and biodiversity (speciation and
extinction) that result from the following: natural causes, changes in climate,
human activity, and the introduction of invasive, non-native species.
6.3 Use a food web to identify and distinguish producers, consumers, and
decomposers, and explain the transfer of energy through trophic levels.
Describe how relationships among organisms (predation, parasitism,
competition, commensalism, mutualism) add to the complexity of biological
communities.
6.4 Explain how water, carbon, and nitrogen cycle between abiotic
resources and organic matter in an ecosystem, and how oxygen cycles
through photosynthesis and respiration.
The part of the
natural world that
ecology deals with is
called the
biosphere.
The biosphere is the
portion of Earth that
can support life.
The biosphere extends as high into the sky
that we find life and as deep into the Earth
as we find living things.
Scientists often view the whole biosphere
as if it were one whole organism. This is
known as the Gaia Hypothesis.
What is the Gaia Hypothesis?
The Concept of Scale is applied to the biosphere through the levels
of organization. In ecology we study six of these levels.
• Biosphere is divided into ecosystems.
• Ecosystems are divided into biomes.
• Biomes are divided into communities.
• Communities ( aka. Biocoenosis) are
divided into populations.
• Populations are divided into individual
organisms of particular species.
 Large Importance on Populations!
because evolutionary pressure is
applied to populations rather than the
other levels of organization in biology.
• Individual organism (from a Species that have
evolved from a common ancestry and share common
anatomy and physiology).
Ecologists study the interactions and interdependences between living
things and their stimuli.
Organisms have interactions and interdependence between each other with
their environment.
Interaction means there is a relationship between two or more organisms.
Interdependent means that these organisms interacting are dependent
upon each other.
Living things are affected by the interaction and interdependence with
other living things, and with the physical environment.
As you recall one of the characteristics of living things is that living
organisms respond to stimuli.
Ecologists study the interactions
and interdependences between
living things and their stimuli.
Discuss the key concepts of
this unit.
Light energy from the sun is captured and transformed into chemical
energy (carbohydrates) in the process of photosynthesis. The energy
passes through the environment from one organism to another via the
feeding relationship.
This energy is passed through carbon-based
molecules and other nutrients
Define These terms:
Predator
Consumer
Heterotroph
Abiotic
Prey
Producer
Autotroph
Biotic
What is one amazing predator
alive today? Give me 5
interesting facts about it.
Energy From the Sun Cycles Through the
Environment Via the feeding relationships.
Light energy from the sun is transformed into chemical energy by
photosynthesis. The energy as carbon chemical molecules can
then be passed through the ecosystem from one organism to the
next.
The Feeding Relationships:
1. Autotroph: self-feeders
• Photosynthetic
• Chemosynthetic
2. Heterotroph: feeds on others
• Herbivores eat plants
• Carnivores eat meat
• Omnivores eat plants & meat
• Detritivores (aka decomposers)
eat decaying matter
What are the feeding relationships?
Living Relationships ( aka. Symbiosis)
Predation (aka. Predator/prey relationship, one
organism, the predator, hunts another, the
prey)
Commensalism (a relationship where one
organism benefits and the other isn’t helped or
hurt.
Mutualism (interactions where both organisms
benefit from the relationship)
Parasitism (relationship where one organism
benefits from the interaction and the other
organism is harmed)
Amensalism (relationship where one species
is not effected by surrounding organisms but
negatively effects its neighbors, usually
through chemicals)
What is
symbiosis?
In your own words, please explain these
terms in your own words
Economic
Environmental
Social
Mutualism
Amensalism
Commensalism
Symbiosis
Parasitism
Predation
What is predation?
Predation is a relationship where
one organism is hunted and
consumed by another organism.
The classic and best studied
example of predation is the
relationship between the lynx and
the hare.
A classic example of commensalism is the cattle egret ( Bubulcus ibis) and
cattle or other grazing animals.
As the cattle eat the grass
insects are forced out into
the open where the egrets
eat the insects. The cattle
is not benefited nor
harmed, but the egret is
benefited by getting an
easy meal.
What is
commensalism?
Mutualism is a symbiotic relationship where both organisms benefit from
the relationship.
An example of mutualism would be
bees pollinating flowering plants. The
bees get nectar for making honey and
the plants are pollinated.
Many people use the word symbiosis
as a synonym for mutualism, but you
know that symbiosis is a bigger
concept than just mutualism.
What is mutualism?
Parasitism is a living relationship where one organism benefits by the
relationship at the expense or harm of the other.
An example of parasitism is the
relationship between dogs, (or other
animals) and ticks.
Another example would be the plant
mistletoe. mistletoe is a parasite.
Mistletoe lives by attaching itself to
trees or shrubs and drawing nutrients
from the sap of its host.
What is parasitism?
Amensalism is a symbiotic relationship where the central organism is
neither harmed nor benefited, while other neighboring organisms are
harmed often by a chemical produced by the central organism.
A well known example comes from the
American black walnut tree which
produces an allelopathic chemical that
interferes with the growth of other
plant that are near the black walnut
tree.
What is
amensalism?
There are two basic types of amensalism:
competition, a stronger organism
excludes a smaller or weaker one from living
space or deprives it of food
antibiosis, in which one organism is
unaffected but the other is damaged or killed by a
chemical secretion.
Food Chains are simple models for explaining energy and matter’s movement
via the feeding relationships, while food webs are more complex models of
networks of food chains.
Nutrient cycles (aka. biogeochemical cycles) show how matter (often as one
element) moves through the environment.
The carbon cycle is the
key biogeochemical cycle
in biology because the
molecules that make
living things are
molecules that are held
together with the
element
carbon. Carbon-based
molecules are also
known as organic
molecules.
Notice how photosynthetic
autotrophs and the
feeding relationships are
part of the carbon cycle.
What are biogeochemical cycles? What is the
carbon cycle?
We used the concept of
scale to group organisms
by their similarities with
the taxonomic rankings
In Biology, we also use the
concept of scale to organize the
amount of matter or life being
studied at once. This called the
Levels of Organization.
I like to think of Ecology as the BIG PICTURE of Biology. How organism fit
into nature. Ecology deals with the Big Picture of the levels of organization
in biology by starting in the middle with individual organisms, then
enlarges its view to populations, then expands again to communities then
to biomes and ecosystems, and finally to the largest scale that we talk
about in biology the entire biosphere.
From largest to smallest
Biosphere
Ecosystems
Biomes
Communities
Populations
Individual Organism
Discuss the
levels of
organization in
ecology.
When a property (or trait) at one level of organization becomes a
completely new trait as you change level of scale, the new property is
called an emergent property.
Example: Water
Water, (H2O) is made when 2 hydrogen atoms bond with an oxygen atom.
The molecule H2O has
completely different
properties than either
hydrogen or oxygen . The
properties of water
emerge by changing the
level of scale from atoms
to molecules.
What are emergent
properties?
Note that emergent properties are an important part of
applying and understanding the concept of scale in
science, and therefore understanding science.
1. Individual Organisms
An individual organism possesses all the characteristics of life; a
living thing.
Example: a zebra. There are different types or species of zebras; we
are referring to Equus quagga or the plains zebra.
We can study a single Equus
quagga but to understand the
zebra we must also study the
interactions and
interdependence it has with
other Equus quagga
• Mating
• Herd protection
• Coloration
What is the most obvious
characteristic or physical
property of a zebra?
2. Population
Population: a group of organisms of one species that interbreed and live in
the same place at the same time.
Example: a herd of Equus quagga
Members of one population are
diverse due to slight DNA
mutations This diversity means
that some members of the
population are better suited to
win that competition while
other members are less fit for
survival.
We call this diversity variation.
Members of populations
compete with each other when
resources are scarce. So , as
grass becomes scarce these
zebras will struggle against
each other for survival.
Explain a biological population.
Even though there is competition
between members of a population,
members of populations rely on each
other for survival.
2. Population (cont.)
Earlier we discuss the most obvious characteristic of a zebra.
What do the stripes on a zebra
become when you study a
population of zebras?
An individual zebra has stripes a
population of zebras have
camouflage.
Stripes on individual zebras
becoming camouflage in a
population of zebras is an
example of an emergent
property.
3. Community
Community is a collection of interacting populations. We sometimes see the
term biocenosis (biocoensis is an alternative spelling) used to describe a
collection of interacting populations in nature.
Example: a herd of elephants, a pride of lions, a herd of giraffes and a herd
of wildebeest but also the populations of plants, bacteria, fungi and protist
that all live together in the same habitat at the same time.
A change in one population in a community
causes changes in the other populations of
the community.
A change in the zebra population will
effect the other populations in the
Serengeti. Example: the relationship
between zebras and lions.
Give an example of a
biological community.
Let’ see this using predation as an example
3. Community (cont.)
Explain a biological community.
Lions, (Panthera leo) and Zebras, (Equus quagga) have a predator/prey
relationship.
Here is a graph representing
two populations, one predator
the other prey. Notice how a
change in the density of one of
the populations influences the
density of the other population
over time.
4. Ecosystem
What is an ecosystem?
Ecosystems are a consideration of the interactions
among populations in a community and the communities
physical surroundings; or abiotic factors.
Example: the Serengeti Grass Plain of Tanzania Africa.
Here are a few more photos to give you a better idea
of what this ecosystem is like.
Below are two NASA satellite
pictures of the Serengeti taken
at different times of the year.
4. Ecosystem (cont.)
What are biomes? Give examples.
Biomes
• Biomes (another way to look at ecosystems)
• Biomes are the world’s distinctive types of ecosystems.
• Biomes are classified by the plant populations found in them.
• Biomes are known for unique climate and unique organisms that have
evolved to better compete and survive in those climates.
Examples of biomes:
Tundra:
Arctic Tundra
Alpine Tundra
Forest:
Boreal forest (Taiga),
Deciduous temperate forest,
Tropical forest (jungle)
Desert:
hot dry desert,
semiarid desert,
cold desert.
Grassland Savannah
Aquatic Freshwater
Aquatic Marine (Saltwater)
5. Biosphere
The Biosphere is the portion of earth that can
support life or possible ecosystems.
The Earth’s atmosphere is in fact
dependent on the biosphere for
regulation. Water, oxygen, carbon,
phosphorous and nitrogen are all
cycled through the biosphere.
Scientists divide the earth into
atmosphere (air), lithosphere
(earth), hydrosphere (water), and
biosphere (life).
What is the Biosphere?
The atmosphere as we know it is a
product of life. The atmosphere is
made by the biosphere, and life now
depends on the atmosphere. They are
interdependent. Many of the
elements that cycle in the earth’s
systems pass through living things as
part of nature’s cycle.
• Individual
organisms
• Populations
• Communities
• Ecosystems
• Biomes
• Biosphere
Explain this
overview of
the levels of
organization
in ecology.
What is ecology?
Which is bigger: knowledge or science, science or biology, biology or
ecology?
What is the biosphere?
What do biotic and abiotic mean
What are the levels of organization in ecology?
What are interactions and interdependence?
What is a population in ecology?
What is a species?
What are herbavores, carnivores, detritivores, and omnivores?
What are predator and prey?
What is a food chain?
What is a food web?
What is a biogeochemical cycle?
Answer 3 of these
questions.
What are the levels of organization studied in biology?
What are the levels of organization studied in ecology?
What concept in science are we using when we divide biology or ecology into
different levels of organization?
What do biotic and abiotic mean
What are the differences between biology and ecology?
What are the differences between the levels of organization studied
in biology and in ecology?
What are properties?
What are emergent properties?
When do emergent properties emerge?
In biology, what is meant be the term population?
What type of ecosystem is the Serengeti Plain?
Answer 3 of these questions