http://www.cs.umbc.edu/courses/undergraduate/201/fall06/projects/p1/fox-rabbit.jpg
http://www.univie.ac.at/zoologie/ecophys/crabsp-300dpi.jpg
Ecological
Relationships
How do biotic
factors
influence
each other?
Ecological Relationships
Biodiversity = the
number of species in an
ecosystem
Territory = space
claimed by an
individual organism
Ecological Equilibrium =
state of “balance” in an
ecosystem
http://www2.warwick.ac.uk/about/environment/faqs/biodiversity.jpg
Ecological Relationships
• NICHE - Role of organism
in the ecosystem (job)
• NICHE DIVERSITY –
Number of niches in an
ecosystem; often
determined by abiotic
factors
Abiotic = non-living
A niche is the
sum of all
activities and
relationships
a species has
while
obtaining and
using
resources
needed to
survive and
reproduce
Competition:
• When species or
individuals “fight” for
the same resources.
The “fight” may be indirect
… individuals may never
directly contact each other.
– E.g., Food, shelter….
• KEYSTONE
PREDATOR/SPECIES -
A predator that
causes a large
increase in diversity
of its habitat.
http://www.butler.edu/herbarium/prairie/prairie42004.jpg
Two species with
Losing a keystone
similar needs for
species usually
same limited
disrupts
many
resources
cannot
ecological
coexist.
relationships.
Herbivory:
http://images.inmagine.com/168nwm/creata
s/cr15169/cr15169065.jpg
http://www.smilinglizard.com/1a291aa0.jpg
• A primary consumer
feeds on a producer.
A fruit bat eating
a papaya
A woodchuck eating
wild clover
http://www.citypaper.net/blogs/clog/wpcontent/uploads/2007/06/close-up-bald-eagle-eating.jpg
• A consumer
feeds on another
consumer.
A lion eating zebra.
An eagle eating halibut.
http://nationalzoo.si.edu/Publications/ZooGoer/2006/3/IMAGES/lion_zebra.jpg
Predation:
• A long-term relationship where two
species live closely together and at
least one benefits directly from the
relationship.
http://www.floridastateparks.org/maclaygardens/images/wallpaper/1024-PL-MAC-Symbiosis-MarkFerrulo.jpg
Symbiosis:
Mutualism:
• Both organisms benefit from the
relationship.
• Win-Win situation!
http://tumi-educational-resources.org/Educational%20%20Videos.htm
Commensalism
• One organism
benefits, the other
one is unaffected.
• Win-Neutral
relationship
Parasitism
• One organism benefits, the other one
is harmed!
• Win-Lose relationship
• Parasites rarely kill their hosts…it
would require them to get another
one!
Ecological Relationships
• Biological Magnification — Increasing
concentration of poisons in organisms in
higher trophic levels in a food chain or
web.
Many
toxins in
the water
Many
toxins in
the
person
• Biological
Magnificationaccumulation of
increasing amounts of
toxin within tissues of
organisms.
Video on Biological
Magnification