Download communities

COMMUNITIES
HOW DO COMMUNITIES OF
ORGANISMS INTERACT WITH
EACH OTHER?
Communities
Definition
• groups of different populations of
organisms living together in the same
place at the same time
• Communities interact through competition,
predation, and symbiotic relationships
What must all organisms in a
community have?
• Habitat – Where the organism lives.
– Ex. Bird lives in the nest of a tree.
• Niche - The organism’s role in the
community.
– Ex. Scavenger, Predator, Prey
NOT ENOUGH FOR ALL
• Hey hey hey I see some nice fruits on that
tree but it looks like those finches bird are
also have their eyes on it. I don’t even
think there are enough for our little blue jay
flock let alone them. LET’S GET IT!
1-COMPETITION: FIGHT FOR
RESOURCES
• INTRASPECIFIC- competition
within the SAME species
• INTERSPECIFIC- competition
among different species
HIDE OR I WILL GET YOU
• I AM ALWAYS IN FEAR OF THAT
JAGUAR COMING OUT OF THE BLUE
TO KILL ME FOR FOOD, BUT I HAVE TO
LOOK FOR SOMETHING TO EAT… A
HYENA GETS HUNGRY TOO!!
2-PREDATION
• PREDATOR- PREY RELATIONSHIP
Organisms in a community must interact in
a predator-prey relationship to obtain food
for survival.
Predator/Prey Graph
Predator/prey
relationship can
control
populations
3-SYMBIOTIC RELATIONSHIPS
SYMBIOSIS: CLOSE ECOLOGICAL
RELATIONSHIP BETWEEN TWO OR
MORE ORGANISMS OF A DIFFERENT
SPECIES
YOU ARE MY FRIEND…AREN’T
YOU?
• I FEEL THAT OUR FRIENDSHIP IS AN
EQUAL PARTNERSHIP. YOU HELP ME
WHEN I NEED IT AND LIKEWISE I HELP
YOU. THIS RELATIONSHIP IS
GREAT…WE ARE IN SYMBIOSIS
MUTUALISM RELATIONSHIP
• BOTH ORGANISMS BENEFIT FROM
THE RELATIONSHIP
– BACTERIA IN OUR STOMACH BACTERIA
HELPS US DIGEST FOOD, BACTERIA HAS
A HOME
– ANTS LIVING ON APHIDS(PLANT) ANTS
FEED ON SUGARY APHID, ANTS
PROTECT THE PLANT
SOMETIMES I FEEL USED
• YOU KNOW, WE ARE GOOD FRIENDS,
BUT SOMETIMES I FEEL LIKE YOU ARE
ASKING ME TO HELP YOU OUT ALL
THE TIME…TESTS, HW, PROJECTS. I
AM GETTING QUITE SICK OF IT AND
FEEL HURT BY IT
PARASITISM RELATIONSHIP
• ONE ORGANISM BENEFITS THE
OTHER IS HARMED
– Virus infects a cell
– Fleas on a dog
– Mosquito bites us
I REALLY DON’T CARE, IT
DOESN’T BOTHER ME
• YOU CAN COPY MY WORK ALL YOU
WANT, AS ALONG AS WE BOTH GET
THE SAME GRADE
COMMENSALISM RELATIONSHIP
• ONE ORGANISM BENEFITS THE
OTHER IS NOT HARMED
– BARNACLES ON A WHALE’S BODY
– REMORA FISH ATTACHES ITSELF TO A
SHARK
WRITING RELATIONSHIPS IN
SHORTHAND
• MUTUALISM ( +/+ )
• PARASITISM (+/ -)
• COMMENSALISM ( +/ 0)