Download Relationships between populations

REL ATIONSHIPS
BET WEEN
POPUL ATIONS
7 TH G R A D E S C I E N C E
3 MAIN RELATIONSHIPS
• Symbiosis
• Predation (Predator/Prey)
• Competition
OUR GOAL FOR SYMBIOSIS IS TO
ANSWER THESE QUESTIONS:
• What is symbiosis?
• What are the different kinds of symbiosis?
• What are some examples of symbiosis?
SYMBIOSIS
What it means:
•Two organisms that live together
•Temporarily or for a longer time
•At least one of the organisms
benefits from the relationship
W H AT A R E T H E
DIFFERENT KINDS
OF SYMBIOSIS?
Mutualism
Commensalism
PA R A S I T I S M
both organisms
benefit
one organism
benefits
one organism
is unaffected
one organism
benefits
one organism
is harmed
Mutualism
Organism One
Organism Two
Commensalism
Organism One
Organism Two
Parasitism
Organism One
Organism Two
Acacia Plant & Ants
The ants lay eggs on
acacia tree so they get
a nice safe place for
their eggs. The acacia
covers the infected
area with brown flesh
(called a gall.) The
plant has to use
valuable resources to
create the gall.
What symbiotic
relationship is this?
parasitism
Loa Loa Worm & Human
This worm infects
human the blood
stream and gets a
nice warm safe
home there. The
human may go
blind or have other
complications as a
result.
What symbiotic
relationship is this?
parasitism
PREDATOR-PREY
RELATIONSHIPS
Predation - (Predator/Prey)
Learning Objectives
Be able to describe the relationship between predators and
their prey.
Animals that eat other animals
Populations of animals are often limited by the amount of food.
What are animals that eat other animals called?
predators
What are the animals that predators eat called?
prey
To do: Define the words Predator and Prey and give an
example of each.
Prey Adaptations – General
Prey have adaptations to detect and prevent being eaten by
predators.
venomous coral snake
mimicry
speed &
keen senses
camouflage
warning
colors &
patterns
scarlet kingsnake
Predator Adaptations – General
Predators have adaptations to catch and consume their prey.
birds of prey have
keen eyesight and
sharp beaks and
talons
camouflage
allows predators
to blend in with
their
surroundings
treefrogs have
special pads on
their feet so
they can cling to
vertical surfaces
venomous snakes have
poisonous venom to
subdue their prey
kingsnakes
are
immune to
the venom
of
venomous
snakes
Can you find the camouflaged
predators?
1
3
2
4
8
6
7
5
WHAT IS COMPETITION?
All living things need natural resources, but the problem is
that there is not enough for everyone. This means that
individuals have to fight for them in order to survive.
This struggle for resources is called competition.
WHO COMPETES?
Competition for
resources between
members of
different species is
called interspecific
competition.
Competition for
resources between
members of the same
species is called
intraspecific competition.
Different species = Interspecific
Same species = Intraspecific
WHAT DO ANIMALS COMPETE FOR?
There are four resources for which animals compete.
What are they?
 food
 water
 mates
 land (territory)
Which resource is
not relevant for
interspecific
competition?
Members of different species will not compete for
mates.
WHAT DO PLANTS COMPETE FOR?
Competition between plants may be less noticeable than
competition between animals but it still takes place.
What four things do plants compete for?
 light
 water
 minerals
 space