Download Organisms Can Interact in Different Ways

ORGANISMS CAN INTERACT IN
DIFFERENT WAYS
You will learn:
About different types of interactions in an ecosystem.
How some species benefit from interactions.
How some species are harmed by interactions.
ORGANISMS INTERACT IN DIFFERENT WAYS
• The human community competes and cooperates.
• Other biological communities do the same.
• They share a habitat and resources in the habitat.
• How different organisms interact depends on their relationship to each other.
ORGANISMS INTERACT IN DIFFERENT WAYS
• A robin in a meadow picks at soil, pulls out worm and swallows it.
• This is an interaction: one eats, the other gets eaten.
• Organisms compete.
• The robin had to compete with a chickadee to get the worm.
• Organisms cooperate.
• Ants work together to build a nest, collect food, defend their colony.
QUESTION…
• Name three ways organisms may interact with each other in an
ecosystem.
• Sharing food
• A water source
• Living in the same place
PREDATOR AND PREY
• Predator: the animal that eats another
• Can affect how members of prey populations are distributed
• Wildebeests travel in herds for protection
• Sick and old members are usually eaten
• Prey: the animal that is eaten by a predator
• Affect the location and number of predator populations
• Ex. Some birds are predators feeding on insects. One factor that may affect the
movement of birds is the availability of insects .
COMPETITION
• Competition: the struggle between individuals or different
populations for a limited resource
• May occur within the same species in an ecosystem
• Ex. Plants compete with each other for space, light, and nutrients
• Creosote bushes produce a toxin from their roots that prevent other
Creosote bushes from growing
COMPETITION
• Also occurs between members of different species.
• Ex. In Indonesia, vines called strangler figs compete with trees for light,
water, and nutrients. Attaches to host tree, surrounds and eventually kills
the tree.
• Infer: Do you think the strangler fig could survive on its own?
STRANGLER FIG
• What is it like on the floor of
the rain forest?
• Deep shade, damp, moist
• What is at the top of the
rainforest?
• Lots of sunlight, leafy
• What does the tree give to the
fig vine?
• Support so it can grow up
towards the light
COMPETITION
• More Examples:
• Hyenas and vultures compete for carcass’
• Wolves compete with each other over territory
• What sort of resources do plants and animals compete for?
• Space, light, water, and nutrients
COMPETITION
• Does NOT occur in all populations that share resources.
• Many species live together without causing harm
• Ex. Maple trees, Oak trees, and Birch trees all live together in the forest
• Ex. Deer and rabbits live together
SO….
• In what ways do organisms of the same or different species
compete?
• For food, space, water, other resources
• What groups of organisms compete for mates?
• Males or females of the same species
COOPERATION
• Cooperation: an interaction in which organisms work in a way
that benefits them all
• Some animals cooperate when hunting. Name some.
• Killer whales, lions, wolves
• Ants, bees and termites cooperate.
• Live in colonies
• Have different jobs/responsibilities
FORMATIVE ASSESSMENT
• When animals mark their territory, how are they relating to other
members of their species?
• They are competing.
• How are they relating when they hunt in packs?
• They are cooperating within their species, and they are preying on
another species.
SURVIVAL
• The Survival of one species might depend on another species.
• One species depends on the action or presence of another.
• One species gets something it needs to survive
• Food, reproductive help, protection
• Symbiosis: the relationship between individuals of two different
species
• Symbiosis means “living together”
SYMBIOSIS
• May affect the partners in different ways:
• Both species benefit from the relationship.
• One species benefits while the other is not affected.
• One species benefits while the other is harmed.
SYMBIOSIS- BOTH SPECIES BENEFIT
• Mutualism: an interaction between two species that benefits
both
• Ex. Bees and flowers
• The bee gets food, flower gets pollen from other flowers to produce seeds
• Termites and protozoans
• Termites are able to eat wood because of the protozoans that live in the
termites gut and digest the wood.
• The protozoans get a place to live and the termites get a food source that
no other animal can eat.
ASSESSMENT
•
Which structures and behaviors of the hummingbird
enable it to get nectar from the flower?
• It has a long thin beak and can hover
•
How is the structure of the flower suited to its
interaction with the hummingbird?
• Its blooms are deep; it’s colorful; produces sweet
food; pollen is spread to help reproduction
•
Why is this a good example of mutualism?
• 2 different species interact. They each get a
different need met.
SYMBIOSIS- ONE SPECIES BENEFITS
• Commensalism: a relationship between two species in which
one species benefits while the other is not affected
• Ex. Orchids and mosses
• Grow on tree trunks or branches
• Get light and nutrients that run down the tree
• The tree is not affected
• Remoras hitch a ride on sharks and eat the sharks leftovers
• The shark is not affected
SYMBIOSIS- ONE SPECIES IS HARMED
• Parasitism: a relationship between two species in which one
species benefits while the host is harmed
• Parasites are often tiny and feed off and weaken the host
• Ex. Ticks, lice, mites are external parasites
• Ex. Tapeworms and fungus
IN YOUR NOTEBOOK ANSWER THESE
QUESTIONS:
• 1. Name two ways in which members of the same species
interact.
• 2. In what ways do members of different species interact?
• 3. Give an example of each type of symbiotic relationship:
mutualism, commensalism, and parasitism
• 4. Think of a biological community near you, and give an
example of how one population has affected another.