STUDENT ACTIVITY
Student activity task A
(b) Measuring biodiversity
Practical field work
Students will be introduced to the concept of biodiversity by completing
practical fieldwork in their local area. School s may have existing links with
organisations such as the RSPB, Scottish Natural Heritage, the Scottish
Wildlife Trust, areas of SSSI, local gardens/parks or school grounds.
This task may be a basic survey of a micro habitat to calculate species
richness, species evenness or the species diversity index (Simpson’s).
Alternatively, students could measure the effect of a changing a biotic factor
on the distribution or abundance of an organism. This work maybe completed
either in class or as homework and be submitted as part of a case study or
mini-project.
Learning outcomes
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
Define the terms ‘species’, ‘habitat’ and ‘biodiversity’.
Explain how biodiversity may be identified at different levels (habitat,
species and genetic).
Explain why sampling is important when measuring the biodiversity of
a habitat.
Describe how random samples can be taken when measuring
biodiversity.
Describe how to measure species richness and species evenness in a
habitat.
Use the Simpson’s index of diversity (D) to calculate the biodiversity of
a habitat, using the formula D = 1 – (Σ(n/N) 2 ).
Outline the significance of both a high and low value of Simpson’s
index of biodiversity (D).
Use a dichotomous key to identify plants, animals or microorganisms.
This activity will allow students to:
 demonstrate skilful and safe practical techniques using qualitative and
quantitative methods with appropriate risk management
 make and record valid observations and measurements
 interpret results to explain patterns and trends, and to reach valid
conclusions using scientific knowledge and understanding
 comment on the reliability and validity of data
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STUDENT ACTIVITY
 assess the limitations of data collection strategies and suggest simple
improvements.
Example projects
Compare two freshwater habitats: a stream and a pond.
Investigating pollution using lichens as indicators .
Identify which trees have the highest biodiversity.
Investigate the effects of trampling.
Urban tree survey (may be part of a national initiative; see
http://www.nhm.ac.uk/nature-online/british-natural-history/urban-treesurvey/index.html)
Information on how to carry out random sampling and suggested project titles
can be found on the London Outdoor Science website: http://www.fieldstudies-council.org/outdoorscience/diy.htm.
Further information and a record sheet for the sampling activity can be found
on the Practical Biology website: http://www.practicalbiology.org/.
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BIODIVERSITY (H, BIOLOGY)
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STUDENT ACTIVITY
Student activity task B
Calculating the number of species on Earth
Measuring biodiversity can be problematic and no one measure alone is
adequate. Two main categories are used:
1.
2.
species richness (the number of different species)
the degree of difference between species (the dissimilarity between
them).
Common problems with measuring biodiversity include:
 Definition of species: the lack of agreement as to what constitutes a
species.
 Organisms are still being discovered and their relatedness measured.
 Different kinds of diversity: an additional limitation of species richness as
a measure of biodiversity is the issue of whether a small number of closely
related species, say two species of mouse, is more or less biodi verse than
an equivalent-sized group of more distantly related species, say a species
of mouse and a species of shrimp.
The task
Students are asked find out how many species are known to scientists and
how many are estimated to be undiscovered. They may be asked to complete
this research in class using online resources and books , or carry out their
investigation as a homework task.
This can also be extended to include research into the numbers of animals
(separated into insects, vertebrates and fish) and how many are plants. It is
interesting to note how many species of plants are used to feed the total
human population on Earth (ie relatively few; this may link into the topic on
food crops).
Students may wish to explore the variety of species online on the
Encyclopaedia of Life website: http://www.eol.org/.
Other resources, such as the Blue Planet series (particularly The Deep) , may
be used to illustrate that there are many species that have not yet been
discovered.
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STUDENT ACTIVITY
Student activity task 5 will address the following statement from the content
tables:
Research the importance of producing a central database of all known
species and the difficulties involved in ensuring its accuracy. It is estimated
that there are about 2 million known species. Of these, about half are
animals, most of which are insects. Of the vertebrate animals, most are fish.
There are about 0.25 million species of flowering plants.
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BIODIVERSITY (H, BIOLOGY)
© Learning and Teaching Scotland 2011
STUDENT ACTIVITY
Student activity task C
Why is maintaining biodiversity important?
Maintaining biodiversity is important for many reasons. Actions to maintain
biodiversity must be taken at local, national and global levels. Students will
be given the opportunity to carry out their own research to achieve the
following.
Learning outcomes
(a)
(b)
Outline the reasons for the conservation of animal and plant species,
with reference to economic, ethical and aesthetic reasons .
Discuss the consequences of the loss of genetic diversity and extinction
for humans.
Students may complete this task in class or as homework. They will be asked
to research why biodiversity is important to humans. Online resources for this
task include a document produced by the United Nations Environment
Programme: http://www.unep.org/geo/geo4/report/05_Biodiversity.pdf
The Natural Environment Research Council (NERC) also provides an
introduction to biodiversity:
http://www.nerc.ac.uk/research/issues/biodiversity/
Some answers may include:
 Plants and animals could provide us with additional foods, medicines and
other products that will save lives and be useful in a changing climate .
 Biodiversity helps maintain important ecological proce sses such as oxygen
production, pollination and flood control that in turn help support all life
on Earth.
 Our lives would not be as rich if we reduced biodiversity (aesthetic
reasons).
 Biodiversity is important for recreation, for example camping, hiking,
fishing and bird-watching.
 Conservation of species is important for future generations.
This list may form the basis of a discussion of which are considered to be
most and least important reasons for conserving species and why.
Teachers may also emphasise that there are many species that are still to be
discovered and if measures are not taken to protect them then we have lost
potential cures for diseases or new food crops.
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STUDENT ACTIVITY
Student activity task D
Documentary ‘The Crater Lions’
This documentary follows the Tokitok pride of lions that lived near the
Ngorongoro Crater in Tanzania. The group ha s been studied for over 30 years
and the lineage of each lion traced back to a single group of animals. In 1962
a plague of biting flies reduced the number of lions in the population from 70
to 15. This reduced the genetic variation of the population significantly and
the effects of inbreeding depression were evident. During filming a female
lioness called Nimue displayed some unusual behaviour, which, along with
the crook in her tail was believed to be caused by inbreeding. Although the
pride was already small, five cubs were killed during the night while the
documentary was being made. Nimue was believed to be behind this and as a
result was forced out of the group.
This documentary provides a good introduction to the study of why genetic
diversity is important and what can happen if continual inbreeding occurs.
Detail of the film can be found at the Public Broadcasting Service (PBS)
website: http://www.pbs.org/wnet/nature/craterlions/index.html
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