Download Notes #2

LaVigne
Environmental Science
Living Things in Ecosystems
Chapter 2
Notes #2
How species interact with each other
►5
Major Interactions Among Biotic Factors
in an Ecosystem
 Predation
 Competition
 Parasitism
 Mutualism
 Commensalism
How species interact with each other
Predation
► On organism kills& eats
another organism
► Predator – the killer/eater
► Feed on the young & weak
► Limits the size of prey
populations
► Prey – gets eaten/killed
► Prey declines the predators
must find other prey
►
How species interact with each other
Predation
Examples
How species interact with each other
► Competition
►2
or more organisms
of the same or
different species
attempt to use the
same limited resources
► can occur evenly if
there’s no contact
(indirect)
► ex-2 insects, same
plant, one feeds during
the day, one at night
How species interact with each other
►
►
►
►
Parasitism
parasite- organisms that
live in or on another
organism & feed on it w/o
immediately killing it
host- organism the
parasite takes nourishment
from
organisms are negatively
affected by parasites
Mistletoe on an apple tree
How species interact with each other
Hungry Tick
Full Tick
Parasitism
How species interact with each other
► Mutualism
►a
cooperative
partnership between
two species in which
both species benefit
► Example you &
intestinal bacteria,
bacteria aids you
w/digestion you give
bacteria warm
home/food
How species interact with each other
Commensalism
► One species benefits,
the other is neither
harmed nor helped
► Remora & sharks attach
to sharks & feed on
scraps from their meals
the sharks aren’t
affected
► Commensalism is very
rare
How species interact with each other
► Commensalism
or Mutualism??
 The sea anemone and the clown fish….
Scientists tend to agree
that it is
commensalism, there is
not sufficient
documented proof that
the anemone benefits in
any way…
Do the fish scare away
other fish/predators???
Finding Nemo….do they
keep the anemone
clean???
Assignments
► Complete
and Hand in the Transparency #2
worksheet with the Section 2.1 on the back
(you received this on Friday)
► Complete
the 2.2 Section review WS