Transcript 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?
(write these down!!!!)
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 also have their eyes on it. I
don’t even think there is 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
Which type of competition will help to control
populations?
Which type of competition will decrease a population?
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 WITH
APHIDS(PLANT) ANTS
FEED ON SUGARY HONEY
PRODUCED BY APHID,
ANTS PROTECT THE
APHIDS FROM PREDATORS
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)