Transcript Ecology - sciencephs

Ecology
The study of the
interactions that take
place among
organisms and their
environment
Aspects of
Ecological Study
Biosphere
 The part of Earth that supports
life
 Top portion of Earth's crust
 All the waters that cover Earth's
surface
 Atmosphere that surrounds Earth.
Abiotic Factors
 Are nonliving factors of an
environment.
 Abiotoic Factors include amount of water
and oxygen, temperature, light, and soil.
Biotic Factors
 Are the living factors of an
environment.
Levels of
Organization in
Ecology
Ecosystem
 All the organisms living in an
area and the nonliving features
of their environment
 Types:
1. Terrestrial = land (forest,
meadow, desert)
2. Aquatic = water (pond, lake,
stream, ocean)
However……..
 An ecosystem can be as large as
the Sahara Desert, or as small as a
puddle, or one tree in the
rainforest!!!
Ex. Pond Ecosystem
Population
 All the organisms in an
ecosystem that belong to the
same species
Community
 All the interacting populations in
an ecosystem
Habitat
 The place in which an
organism lives
 provides the kinds of food and
shelter, the temperature, and the
amount of moisture the organism
needs to survive
Niche
 Is the role and position a species has in
its environment (how it meets its needs
for survival)
 Example: see the soil ecosystem on
pages 44-45 in text…note each
organisms role and how it uses the
resources in its own way to survive
Living Relationships
Photo from: Dr. Todd Huspeni – Animal Parasitology UW-Stevens Point
Symbiosis
 Relationship in which there is a close and
permanent association among organisms
of different species
 Examples: Commensalism, Mutualism,
Parasitism
Photo from: Dr. Todd Huspeni – Animal Parasitology UW-Stevens Point
Commensalism
 Symbiotic Relationship in which one
species benefits and the other species is
neither harmed nor benefited
Ex. Clownfish protected by
anemone…anemone not harmed or
helped
Photo from: Dr. Todd Huspeni – Animal Parasitology UW-Stevens Point
Ex. Spider Crab hitches a
ride from jellyfish
Photo from: Dr. Todd Huspeni – Animal Parasitology UW-Stevens Point
Mutualism
 A symbiotic relationship in which both
species benefit
Ex. Ants
protect acacia
tree by
attacking any
animal that
tries to feed on
it…tree
provides nectar
and home for
ants
Photo from: Dr. Todd Huspeni – Animal Parasitology UW-Stevens Point
Parasitism:
A type of interspecific
interaction where one
species (the host) is harmed
at least in some way by the
other (the parasite).
Tapeworm
Photo from: Dr. Todd Huspeni – Animal Parasitology UW-Stevens Point
Dog hookworm
Photo from: Dr. Todd Huspeni – Animal Parasitology UW-Stevens Point
Filariasis (Elephantiasis)
caused by parasitic worm
Photo from: Dr. Todd Huspeni – Animal Parasitology UW-Stevens Point
Fleas
Photo from: Dr. Todd Huspeni – Animal Parasitology UW-Stevens Point
Lice
Photo from: Dr. Todd Huspeni – Animal Parasitology UW-Stevens Point
Ticks
Photo from: Dr. Todd Huspeni – Animal Parasitology UW-Stevens Point
Learning Targets
 Students will be able to demonstrate how
energy transfers through food webs
 Students will be able to define and give
examples of producers and consumers
Box Jellyfish
 Live off of Northern Australia – in
Great Barrier Reef and in IndoPacific
 Very powerful venom – among most
deadly in world
 Can be fatal to humans – and
survivors will have pain for months
and permanent scars from tentacles
 Up to 15 tentacles grow from each
corner, and tentacles can be up to 3
meters in length!
 Stinging not activated by touch, but
by chemical contained on prey
 Have eye clusters, but lack a central
nervous system, so scientists don’t
yet understand how they see
 Sea turtles are unaffected by the
sting of the jellyfish and regularly eat
them
 Average lifespan less than 1 year
How Organisms
Obtain Energy
The Producers: Autotrophs
 Organisms that use energy from the sun
or chemical compounds to make their
own nutrients (photosynthesis)
Water +
6H2O +
carbon dioxide 
6CO2

glucose + oxygen
C6H12O6 + 6O2
The Consumers:
Heterotrophs
 Organisms that cannot make their own
food and must feed on other organisms
Consumers- 5 Types
 Herbivores - primary consumer – eat
plants only
 Carnivores - higher level consumers –
eat other animals
Consumers – 5 Types
 Omnivores - can fit in at any consumer
level – eat both plants and animals
 Decomposers - break down dead
organisms
 Scavengers - eat dead animals
Food Chain
A food chain is
a simple
model of the
feeding
relationship in
an ecosystem.
Food Chain
The mountain lion is
the second
organism of the food
Because shrubs chain. It eats the
make their own food
deer. It is the
through
secondary
The deer is the
first
photosynthesis,
they
consumer.
areorganism
called of the food
chain to eat the
producers.
shrub. It is the
primary consumer.
For example, shrubs are food for deer,
and deer are food for mountain lions.
Shrubs are the
beginning of the
food chain. They
receive their energy
from sunlight.
Food Chain
Algae make their own
food from sunlight.
They are the basis
for the food chain in
this example.
Generalized Food Web of the
Antarctic
Humans
Blue whale
Sperm whale
Killer
whale
Note:
Arrows
Go in direction
Of energy flow…
Elephant
seal
Crabeater seal
Leopard
seal
Emperor
penguin
Adélie
penguins
Petrel
Squid
Fish
Carnivorous plankton
Herbivorous
zooplankton
Krill
Fig. 4.18, p. 77
Phytoplankton
Food Webs
Food Webs are Food Chains that intersect
each other. Food webs are what really
happens in nature.
Now…let’s do an activity!!
Grab a textbook and turn to page 53 (1 book per
table)…a little background music for you while you get
books
http://www.youtube.com/watch?v=sbWyrcY5i3s
Food Web Activity
 Each group gets a deck of food web cards,
whiteboard, and marker
 Lay out the cards on the whiteboard,
arrange them into a potential food web
 Add 5 organisms of your own to the web
 Connect the webs with the arrows
 Label the autotrophs and heterotrophs
 For each heterotroph ID: carnivore,
herbivore, omnivore, decomposer,
scavenger
Where do decomposers fit
in food chains?
Trophic Level
 Each Organism in a food chain
represents a feeding step in the passage
of energy and materials
How does energy transfer
in a food chain?
 10% rule
 Each organism at a trophic level loses
energy from its food through waste and
metabolic processes. Only 10% of the
energy is used for growth and passed on
to the next level of the food chain
Max Number of Trophic
Levels:
 3–4
 Why?
 Only 10% of energy gets passed on, so energy
dwindles away quickly:
 Mouse eats grass – gets 10% energy
 Snake eats mouse – gets 10% of 10% = 1%
 Hawk eats snake – gets 10% of 1% = 0.1%
Energy Pyramid
Energy Pyramid
 The bars are drawn in proportion to the
total energy utilized at each trophic
Pyramid of Numbers
Pyramid of Numbers
 A bar diagram that indicates the relative
numbers of organisms at each trophic
level in a food chain.
 The length of each bar gives a measure
of the relative numbers.
Pyramid of Biomass
Pyramid of Biomass
 As pyramids of number but uses dry mass of
all organisms at each trophic level.
§ http://www.youtube.com/watch?v=TE6wqG4nb
3M
§ Music review

Does anything else transfer
in a food chain?
 Toxins (heavy metals, DDT, PCB’s) =
stored in the fat of organisms
 Bioaccumulation = accumulation of
toxic chemicals in the tissue of an
organism
 Biomagnification = increase in
concentration of a pollutant from the
environment to the first organism and
subsequent organisms in a food chain
 The higher the animal is on the food chain,
the higher the concentration of toxins
DDT Problem
 Background of DDT
 DDT is a pesticide used for mosquito control and
pest control in agricultural crops.
 DDT accumulation in some bird species resulted in
death, nervous system damage, and reproductive
failure.
 As a result DDT was banned in the United States in
1972.
DDT is broken down by organism and
stored in fat = Damage = decrease
population
 Reproductive failure (in birds/eagles- eggshell
thinning)
 Immune system problems
 Nervous system damage
 Death
Bioaccumulation Factor
 The concentration of a chemical/toxin in
tissue divided by its concentration in the
diet