Download RELATIONSHIPS AMONG LIVING THINGS

RELATIONSHIPS
AMONG LIVING
THINGS
Day 3
Interactions Among Living
Things
• Living things depend on one another for
survival
• An organism may have multiple
relationships, depending on the organism
it interacts with
Competition
• Can be between same species
or different species
• Occurs when resources are
limited:
–
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Food
Water
Space
Mate
• Fight occurs in order to gain
resources needed
Predation
• An animal catches
and feeds on the
captured organism
• Predator-hunter
• Prey-hunted
Symbiotic Relationships:
MUTUALISM
• Symbiosis-a close
relationship between
organisms that last
over a period of time
• Mutualism
– Both organisms benefit
from the relationship
– Benefit include food,
shelter, protection
Plover and Crocodile
Symbiotic Relationship:
PARASITISM
• One species benefits but the
other specie gets harmed
from the relationship
• Benefit can be food, shelter
or protection
• Parasite-benefits
– May reside inside
(endoparasite) or outside
(ectoparasite)
Mosquito and Human
• Host-gets harmed
• The parasite has to ensure
that the host does not die.
– What happens if the host dies?
Tapeworm and Human
Symbiotic Relationship:
COMMENSALISM
• A relationship wherein
one benefits while the
other one neither
benefits, nor gets
harmed or dies.
• Commensal- the
organism that benefits
• Host- the organism
that neither benefits
nor gets harmed
http://www.youtube.com/watch?v=TGRuen6BMbw
Ecological Relationships:
EXAMPLES
Video Segments: The Secret World of Sharks and Rays | Nature | PBS
Video Segments: The Secret World of Sharks and Rays |
Nature | PBS
Symbiotic Relationships:
1. Yellow- billed Oxpecker eating ticks off the back of a Hippo.
Mutualism
2. Elf Owl and Roadrunner both trying to eat an insect.
Competition
3. Coral provides home for algae. Algae produces food for coral.
Mutualism
4. Tiger hunting a rabbit.
Predation
5. Wasp lays eggs on Tomato Hornworn caterpillar. Eggs hatch, burrow
into caterpillar and eat it for food.
Parasitism
6. Red-tailed Hawk builds nest in branches of Saguaro catcus. Cactus is
not harmed.
Commensalism
SURVIVAL OF THE FITTEST
What does “Survival of the Fittest” mean?
Nature’s way of determining traits needed by an organism to
help it’s species survive- Natural Selection
 The traits that help an organism survive in a particular
environment /habitat
http://app.discoveryeducation.com/search?Ntt=natural+selection
About.com: http://science.discovery.com/videos/100-greatestdiscoveries-shorts-natural-selection.html
The Mono Lake Story
The Mono Lake Story - YouTube
Is there a relationship which
you think is the best? Why do
you say so?
Picture sources
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susty.com
thefeltsource.com
myfourthirds.com
catalog.beacon-ridge.com
static.seekingalpha.com
classes.dma.ucla.edu
Bcscience.com
bio.miami.edu
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physicalgeography.net
webecoist.com
themain-ingredient.info
ncwildlife.org
wikimedia.org