Transcript File
Which principle
does
this
demonstrate?
Mr A Lovat
1
Wordwall or Crossword
Fundamental / The type of niche that an organism will occupy if there is no outside
source of competition (1)
Realised / The type of niche that an organism will occupy when another species is in
competition with it (1)
Resource partitioning / A way to divide up resources to ensure two species in
competition don’t become extinct (2)
Competitive exclusion / A principle to explain why when two species are in direct
completion one goes extinct (2)
Grey squirrel / A species that is in danger in England due to a larger and better
adapted competitor being introduced by people in the early 1900s (2)
Zone of stress / Range of conditions in which an organism may die if zone of tolerance
not returned to normal (3)
Zone of tolerance / Range of conditions in which an organism can tolerate (3)
Zooxanthellae / The symbiotic photosynthetic organism found within coral species (1)
Symbiotic / Organisms that are reliant on another to the point that one cannot survive
without the other (may be endosymbiotic) (1)
Coral bleaching / Name of the process in which corals lose their syumbiotic
zooxanthellae (2)
Homework
1. Collect in ‘Interactions of animals’ summary
2. Remember, 2 min talk on keystone species
tomorrow
3. Use the ISSG website to research an invasive
species and evaluate current methods being used
to control their numbers
11th hour
https://www.youtube.com/results?search_q
uery=the+11th+hour
http://www.imdb.com/title/tt0492931/
https://www.youtube.com/watch?v=C14SrSv270
C.3 Impacts of humans on ecosystems
Essential idea: Human activities impact on ecosystem
function.
Rhododendrons are beautiful eye catching shrubs that grow
in many gardens throughout the world. Rhododendrons are
native to alpine regions in Asia. Since their introduction to
non-native regions they become an invasive species causing
major disruptions to ecosystems, e.g. in Western Europe
they have out-competed local woodland plants causing
major reductions in local biodiversity.
Understandings, Applications and Skills
Statement
C.3.U1 Introduced alien species can escape into local ecosystems and become
invasive.
C.3.U2 Competitive exclusion and the absence of predators can lead to reduction
in the numbers of endemic species when alien species become invasive.
C.3.U3 Pollutants become concentrated in the tissues of organisms at higher
trophic levels by biomagnification.
C.3.U4 Macroplastic and microplastic debris has accumulated in marine
environments.
C.3.A1 Study of the introduction of cane toads in Australia and one other local
example of the introduction of an alien species.
C.3.A2 Discussion of the trade-off between control of the malarial parasite and
DDT pollution.
C.3.A3 Case study of the impact of marine plastic debris on Laysan albatrosses
and one other named species.
C.3.S1 Analysis of data illustrating the causes and consequences of
biomagnification.
C.3.S2 Evaluation of eradication programmes and biological control as measures
to reduce the impact of alien species.
Guidance
Understandings, Applications and Skills
Statement
C.3.U1 Introduced alien species can escape into local ecosystems and become
invasive.
C.3.U2 Competitive exclusion and the absence of predators can lead to reduction
in the numbers of endemic species when alien species become invasive.
C.3.U3 Pollutants become concentrated in the tissues of organisms at higher
trophic levels by biomagnification.
C.3.U4 Macroplastic and microplastic debris has accumulated in marine
environments.
C.3.A1 Study of the introduction of cane toads in Australia and one other local
example of the introduction of an alien species.
C.3.A2 Discussion of the trade-off between control of the malarial parasite and
DDT pollution.
C.3.A3 Case study of the impact of marine plastic debris on Laysan albatrosses
and one other named species.
C.3.S1 Analysis of data illustrating the causes and consequences of
biomagnification.
C.3.S2 Evaluation of eradication programmes and biological control as measures
to reduce the impact of alien species.
Guidance
Human Impacts on ecosystems
Watch Leonardo Di Caprio’s message (below) before watching
his very poignant movie “The 11th Hour”
The WWF and UNEP
links gives more
information about
the issues and what
can and is being
done to solve
problems
http://youtu.be/9OhdMULRkAs
http://freedocumentaries.org/documenta
ry/the-11th-hour
http://www.worldwildlife.org/
http://www.unep.org/wed/
What is an alien species?
Do you know of any that you
come across in your
everyday life?
Zebra Mussel
Harlequin ladybird
Cane Toad
Don’t mess
with me
Tilapia
Rabbits
Emerald Ash Borer
C.3.U1 Introduced alien species can escape into local ecosystems and become invasive.
Can you think of an
invasive alien species
that has caused
problems in England?
Understandings, Applications and Skills
Statement
C.3.U1 Introduced alien species can escape into local ecosystems and become
invasive.
C.3.U2 Competitive exclusion and the absence of predators can lead to reduction
in the numbers of endemic species when alien species become invasive.
C.3.U3 Pollutants become concentrated in the tissues of organisms at higher
trophic levels by biomagnification.
C.3.U4 Macroplastic and microplastic debris has accumulated in marine
environments.
C.3.A1 Study of the introduction of cane toads in Australia and one other local
example of the introduction of an alien species.
C.3.A2 Discussion of the trade-off between control of the malarial parasite and
DDT pollution.
C.3.A3 Case study of the impact of marine plastic debris on Laysan albatrosses
and one other named species.
C.3.S1 Analysis of data illustrating the causes and consequences of
biomagnification.
C.3.S2 Evaluation of eradication programmes and biological control as measures
to reduce the impact of alien species.
Guidance
They occupy a similar
neiche… why cant they
both survive?
C.3.U2 Competitive exclusion and the absence of predators can lead to reduction in the numbers
of endemic species when alien species become invasive.
Competitive exclusion principle: Two species cannot occupy the same niche
in a community, as there will be competition for the same resources. When
one species has even the slightest advantage or edge over another then the
one with the advantage will dominate.
Advantages can come in different forms, 5 examples
of advantages between species occupying similar
niches are:
1. High reproductive rate
2. Larger size / more aggressive
3. Faster / more efficient forager
4. Absence of predator
The Super Squirrel
C.3.U2 Competitive exclusion and the absence of predators can lead to reduction in the numbers of
endemic species when alien species become invasive.
Differences?
Why is the grey squirrel a better competitor?
Grey squirrels are better at obtaining food
sources AND eat a wider variety of foods
C.3.U2 Competitive exclusion and the absence of predators can lead to reduction in the numbers of
endemic species when alien species become invasive.
In Britain and in Ireland, the eastern gray squirrel is not regulated by natural
predators.[31] This has aided its rapid population growth and has led to the
species being classed as a pest. Measures are being devised to reduce its
numbers, including one plan for celebrity television chefs to promote the idea of
eating the squirrels.[32] In areas where relict populations of red squirrel survive,
such as the islands of Anglesey and Brownsea, programs exist to eradicate
gray squirrels in an effort to allow red squirrel populations to recover.[33]
Although complex and controversial, the main factor in the eastern gray
squirrel's displacement of the red squirrel is thought to be its greater
fitness and, hence, a competitive advantage over the red squirrel on all
measures.[34] The eastern gray squirrel tends to be larger and stronger than the
red squirrel and has been shown to have a greater ability to store fat for winter.
https://www.youtube.com/watch?v=_ukJF2
b82SU
http://en.wikipedia.org/wiki/Eastern_gray_squirrel
C.3.U2 Competitive exclusion and the absence of predators can lead to reduction in the numbers of
endemic species when alien species become invasive.
•Competition
•Displacement of red squirrels
•Competitive exlcusion?
C.3.U2 Competitive exclusion and the absence of predators can lead to reduction in the numbers of
endemic species when alien species become invasive.
1. Compare the distribution of grey and red squirrels between 1945 and 2010
[3]
2. Suggest a reason for the trend [2]
3. Suggest what may happen to native populations of red squirrels if this trend
is not reversed [1]
4. Suggest a method to control the number of grey squirrels to allow the reds
to recover [1]
C.3.U2 Competitive exclusion and the absence of predators can lead to reduction in the numbers of
endemic species when alien species become invasive.
1. Compare the distribution of grey and red squirrels between 1945 and 2010 [2]
Red squirrels start with high distribution throughout UK whereas greys only found in central
southern parts;
Grey squirrel increase in distrubtion while reds decrease
Grey squirrels dominate England while reds are isolated in northern parts by 2010;
Always few areas of overlap between the two species;
No red of grey squirrels ever found in northern Scotland/western Ireland;
2. Suggest a reason for the trend [2]
Grey squirrels outcompeting reds/better able to obtain resources
Both species occupy a similar niche
Competitive exclusion/no two species can occupy the same ecological niche
3. Suggest what may happen to native populations of red squirrels if this trend is not reversed [1]
Extinction/Competitive exclusion
4. Suggest a method to control the number of grey squirrels to allow the reds to recover [1]
Killing or trapping them/sterilisation/biological control that does not effect reds/ forestry
management to plant trees favourable to the reds etc
Understandings, Applications and Skills
Statement
C.3.U1 Introduced alien species can escape into local ecosystems and become
invasive.
C.3.U2 Competitive exclusion and the absence of predators can lead to reduction
in the numbers of endemic species when alien species become invasive.
C.3.U3 Pollutants become concentrated in the tissues of organisms at higher
trophic levels by biomagnification.
C.3.U4 Macroplastic and microplastic debris has accumulated in marine
environments.
C.3.A1 Study of the introduction of cane toads in Australia and one other local
example of the introduction of an alien species.
C.3.A2 Discussion of the trade-off between control of the malarial parasite and
DDT pollution.
C.3.A3 Case study of the impact of marine plastic debris on Laysan albatrosses
and one other named species.
C.3.S1 Analysis of data illustrating the causes and consequences of
biomagnification.
C.3.S2 Evaluation of eradication programmes and biological control as measures
to reduce the impact of alien species.
Guidance
Cane Toad
Don’t mess
with me
An example where biological control failed
• Cane toad was introduced to Australia to combat the French
Cane beetle and Grey back cane beetle. However, the cane
toad thrived and started to feed on other insects. It took over
other native amphibian habitats and brought foreign diseases
to reptiles.
• They contain a poison in glands in their shoulders and are
poisonous to crocodiles, tiger snakes and dingoes. This is an
example where new introduced organisms can have a
catastrophic effect on an ecosystem.
Biological control for
cane toads
(viruses/parasites etc)
is under development
•Biological control of cane beetle – didn’t work as
ate other species of insect too…
•Competition with native amphibians
•Toxins poison local predators (disrupt food chain)
•Possible extinctions?
C.3.A1 Study of the introduction of cane toads in Australia and one other local example of the
introduction of an alien species.
http://youtu.be/t3ENUqV5-bw
http://youtu.be/gX1FLXEo96g
Cane toad
• http://news.bbc.co.uk/1/hi/world/asiapacific/7970877.stm
• https://maps.google.co.uk/maps?hl=en&tab=wl
• https://www.youtube.com/watch?v=OtMtIItimjQ
C.3.A1 Study of the introduction of cane toads in Australia and one other local example of the
introduction of an alien species.
Rabbits in Australia
• http://www.animalcontrol.com.au/rabbit.htm
NOT TO BE
COVERED IN
LESSON
•No natural predators
•Millions of dollars of crop damage
Read the article:
http://theconversation.com/rabbits-and-biological-control-twounexpected-christmas-presents-11399
Control of Invasive Species
RHDV as a form of biological control
NOT TO BE
COVERED IN
LESSON
C.3.S2 Evaluation of eradication programmes and biological control as measures to reduce the
impact of alien species.
NOT TO BE
COVERED IN
LESSON
C.3.S2 Evaluation of eradication programmes and biological control as measures to reduce the
impact of alien species.
http://www.issg.org/database/welcome/
HOMEWORK for Friday
Research one invasive species and evaluate the management
strategies put in place to control their numbers
Bouvet Island
Why should the
island stay invasive
species free? Do you
agree?
Read the article on a place with no invasive species
•
http://www.newscientist.com/article/mg19426081.600-the-last-place-on-earth-with-no-invasive-species.html?full=true&print=true
•
https://maps.google.co.uk/maps?q=Bouvet+Island&bav=on.2,or.r_qf.&bvm=bv.45512109,d.d2k&biw=1024&bih=571&wrapid=tlif1366623
17174310&um=1&ie=UTF-8&hl=en&sa=N&tab=wl
Exam Question
(a)Discuss the impacts of a named alien species
introduced as a biological control measure.
.............................................................................................
..........................................................................................
..........................................................................................
..........................................................................................
..........................................................................................
..........................................................................................
.........................................................................................
(3)
(Total 5 marks)
(a)
•named alien species e.g. western mosquitofish / small Indian mongoose /
rosy wolfsnail; cane toad
•introduced for removal of crop pests;
•competes with native species;
•no natural predators
•excessive predation on native species that do not have defences;
•impacts industry such as tourism/harvesting of natural resources;
Accept other specific examples of effects.
•3 max