NATIONAL QUALIFICATIONS CURRICULUM SUPPORT
Biology
Unit 2
Activities
[ADVANCED HIGHER]
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Overview of Section 1 – Field Techniques for Biologists
Mandatory Course key area
(SQA Course and Unit Support Notes)
(a) Health and safety
Hazards and risks associated with fieldwork, such as terrain,
weather conditions and isolation must be assessed.
(b) Sampling of wild organisms
The chosen technique, such as point count, transects or
remote detection, must be appropriate to the species being
sampled, to include: quadrats, capture techniques, camera
traps, scat sampling.
Appropriate random, systematic and stratified sampling.
(c) Identification and taxonomy
Methods of identification to include: using expertise,
classification guides, keys or laboratory analysis of DNA,
protein or other molecules.
The concept of taxonomic groupings. Familiarity with
taxonomic groupings allows predictions and inferences to
be made between the biology of an organism and betterknown (model) organisms.
Classification of life into the three domains - archaea,
bacteria and eukaryote. The plant kingdom has major
divisions - mosses, liverworts, ferns, gymnosperms and
angiosperms. The animal kingdom is divided into phyla
including Chordate, Arthropoda, Nematoda,
Platyhelminthes and Mollusca.
Suggested learning activities
(SQA Course and Unit
Support Notes)
Education Scotland
Support Materials
Discuss standard rules for
fieldwork safety
Unit 2 Activity A
(Health & Safety)
Participate in fieldwork.
Identification of sample using
guides and keys.
Unit 2 Activity B
(Sampling wild
organisms)
Awareness of protected species in
Scotland.
In the context of fieldwork,
sample the organisms from a
variety of habitats and attempt to
classify and catalogue them using
keys and other materials.
Visit a botanic garden to learn
more about the major divisions of
plants. Visit a zoological park to
learn more about the animal
phyla.
Undertake fieldwork to study the
invertebrate phyla commonly
found on the shore, in a river or in
woodland.
There are model organisms within
all major taxonomic groups.
Examples of model organisms
include E. coli,
Saccharomyces cerevisiae,
Arabidopsis thaliana, maize, C.
elegans, Drosophila, Hydra,
lamprey, mouse, rat, zebrafish,
chicken, zebra finch.
Unit 2 Activity C
(Identification &
Taxonomy)
PDF File: Identification
of British Land
Flatworms
Useful video/web links
Crash Course Biology
#19 Taxonomy
https://www.youtube.com/watch?v=F38B
mgPcZ_I
Bozeman Science
1. The Three Domains of Life:
https://www.youtube.com/watch?v=wGVg
IcTpZkk
2. Classification of Life:
https://www.youtube.com/watch?v=tYL_8
gv7RiE
(d) Monitoring populations
The use of information on species abundance to assess
environmental impact. Method of mark and recapture to
estimate population size (N = (MC)/R).
Effective and ethical methods of marking to include
banding, tagging, surgical implantation, painting and hair
clipping.
(e) Measuring and recording animal behaviour
Ethograms and time sampling to compare the behaviour of
different individuals of a species.
Identify relevant indicator species
to classify a habitat using the
British National Vegetation
Classification.
Carry out a mark and recapture
experiment using a wild species
or, alternatively, using school
learners to estimate the total
school roll.
Use an ethogram and time
sampling to compare the
behaviour of different individuals
of a species.
Unit 2 Activity D
(Mark & Recapture)
Unit 2 Activity E
(Measuring &
Recording Animal
Behaviour)
Youtube search: Mark and Recapture
https://www.youtube.com/watch?v=tyX79
mPm2xY
Johnny Ball demonstrates technique using
ping pong balls
https://www.youtube.com/watch?v=5DR5
0IgvE7g&list=PLWj677KseF8D2BmgcX
PFOZPTjuxcxE3y5
Use of technique in wild snake populations
http://www.livinglinks.org/resources/materials-forteachers/measuring-behaviour-lesson-plan/
This is an excellent resource that includes
research papers, teacher guides,
PowerPoint etc.
CfE AH - Unit 2 Learning Activity A: Health and Safety
This Learning Activity supports the following Mandatory Key Area:
Unit 2: Organisms and Evolution
1 Field techniques for biologists
(a) Health and safety
The Mandatory Course key area states:
Hazards and risks associated with terrain, weather conditions and isolation must be assessed.
Exemplification of key area:
Fieldwork may involve a wider range of hazards compared with working in the laboratory.
Overview of activity
1.
To familiarize learners with typical fieldwork health and safety guidelines and risk assessments.
2.
To allow learners to gain skills and understanding of the process of developing and following
risk assessment for fieldwork.
Part 1: Familiarisation with typical fieldwork health and safety guidelines
Discuss with class the necessity for biological fieldwork to be a safe activity and for the need to avoid
harm to researchers, the public or the environment.
Learners should examine some examples of good practice. The health and safety policy of your own
school or college may be a good starting point.
In addition, example documents, such as the following, should be made available.
University of Edinburgh: Health and Safety Department
Health and Safety Policy – Part 8 Fieldwork and Outdoor Activities
http://www.docs.csg.ed.ac.uk/Safety/Policy/Part8.pdf
University of York: Department of Biology
Risk assessment of fieldwork activities
http://www.york.ac.uk/biology/intranet/health-safety/fieldwork/risks/
http://www.york.ac.uk/biology/intranet/health-safety/fieldwork/conduct/
University of Oxford: Department of Zoology
Final Honours School, fieldwork safety
www.ox.ac.uk/media/global/wwwoxacuk/localsites/studentgateway/documents/fieldworksafety.pdf
Learners should identify common themes and make a list of the essential hazards that must be
controlled in undertaking fieldwork.
Part 2: Development of a risk assessment for biological fieldwork
Learners should select one of the following activities and develop an appropriate risk assessment for
either:
• Biological fieldwork within the school grounds
• Biological fieldwork in a location close to local facilities and transport links
• Biological fieldwork at a remote location in Scotland or abroad.
Ensure that learners understand the difference between a hazard (something that can cause harm) and
a risk (the likelihood that the harm occurs).
Learners should be encouraged to think through the following sequence:
1. Identify the hazards
2. Evaluate the risks (how likely)
3. Evaluate the severity (how harmful)
4. Identify how the risks and severity can be avoided or reduced
5. Record these safe working practices.
Suitable headings could be:
Physical hazards
Biological hazards
Chemical hazards
Man-made hazards
Personal safety
Environmental impact
The following proforma can be used.
Fieldwork Risk Assessment
Name:
Location:
Dates:
From:
Hazards
Physical
 Extreme weather
 Mountains and cliffs
 Glaciers, crevasses, ice falls
 Caves, mines and quarries
 Forests / woods
 Freshwater
 Sea and seashore
 Marshes and quicksands
 Roadside
 Work at height
Biological
 Poisonous plants
 Aggressive animals or insects
 Pathogenic microorganisms (e.g.
cause of tetanus, leptospirosis)
Chemical
 Pesticides
 Dusts
 Contaminated soils
 Chemicals on site
 Chemicals associated with the
fieldwork activity
To:
Risk
(High,
medium, low)
Severity
(High,
medium or
Low)
Control Measures
(e.g. procedures; equipment;
clothing; skills training;
information)
Man-made
 Electrical equipment, generators and
pipelines
 Vehicles and machinery
 Insecure buildings
 Slurry pits and farming
 Forestry operations
 Military operations
 Recreation
 Excavations and waste disposal
 Boat use
Personal safety
 Lone working
 Attack on person or property
 Political instability, banditry
 Security of accommodation
Environmental impact
 Waste disposal
 Pollution
 Disturbance of eco-systems
Other
 Health & fitness
 Behaviour
CfE AH - Unit 2 Learning Activity B: Sampling wild organisms
This Learning Activity supports the following Mandatory Key Area:
Unit 2 Organisms and Evolution
1 Field techniques for biologists
(b) Sampling of Wild Organisms
The Mandatory Course key area states:
The chosen technique, such as point count, transects or remote detection, must be appropriate to the
species being sampled, to include: quadrats, capture techniques, camera traps, scat sampling.
Appropriate random, systematic and stratified sampling.
Exemplification of key area:
Sampling should be carried out in a manner that minimises impact on wild species and habitats.
Consideration must be given to rare and vulnerable species and habitats, which are protected by
legislation.
Quadrats of suitable size and shape are used for slow-moving organisms; capture techniques for
mobile species. Elusive species can be sampled directly using camera traps or an indirect method
such as scat sampling.
Overview of activity: Content area: Sampling wild organisms (Techniques)
Sampling using a line and belt transect
Background:
The diversity of habitat and biodiversity is impressive across Scotland. We are a country rich in
upland, lowland and coastal environments. Taking an environmental snapshot in the form of a line or
belt transect allows us to understand more clearly the number of species of plants and animals in our
chosen area of study. Sampling allows us to not only identify what species are present in a particular
area but also gives us an indication of their density and distribution. If this is an area that would not be
damaged by regular sampling, it may be possible to build up local data on species biodiversity on an
annual basis.
The decision whether to use a line transect or a belt transect depends on several factors.
Line transects:
Line transects are most useful if you are dealing with an area that has a steep gradient such that
placing quadrats and accurate recording on a steep slope may be difficult. They are also of value if
you want to gather as much useful information as possible in a limited timeframe. In shoreline
transects, if you are dealing with a rapidly incoming tide, conducting a line transect from the low
water line up the shore may well be the most sensible option.
However, a line transect does not give you any information about the relative density of species’
cover in the area as you are studying; it only tells you what species are present lying along the transect
line itself.
Belt:
Conducting a belt transect of an area will give much more detailed information. It is similar to a line
transect but it gives information on species abundance as well as presence or indeed absence. It is
effectively a very wide line transect to form a continuous strip.
Obtaining the detailed information available from a belt transect takes more time.
Line transect: method
Once the area to be sampled has been determined, it should be marked out using string or a long
measuring tape. Use of a GPS camera when recording data from your sample area would allow you to
obtain an aerial photograph of the area from Google earth. Altitude and degree of slope can then be
examined more easily.
Sampling a line transect can be:
Continuous – where a record is made of every species that lies along the transect line along its length.
This can give a lot of information but tends only to be possible over a short distance as the number of
plants/ animals being recorded can be very high.
Interrupted – where a record is made every 0.5 m or 1.0 m along the length of the transect line. This
allows the area to be sampled much more quickly and to gather a more manageable volume of data;
however, the results are less detailed.
Apparatus required:
String/measuring tape sufficient for the area of transect. If you are doing an interrupted line transect
then marking the string with pen every 0.5m/1.0m greatly speeds up the recording time.
Suitable keys/ identification guides to allow accurate identification of the species being assessed.
Sample bags to take back unidentified species (this would only be done if there was a high abundance
of the species and would involve the removal of a leaf or two, not the whole plant) alternatively,
digital photographs can be taken for identification later.
Moisture meter/pH meter /light meter – while line transects focus on ground biodiversity along the
line, it is sensible to take other abiotic factors into account to improve the reliability of your results.
Belt transect: method
Once the area to be sampled has been determined, it should be marked out using string or a long
measuring tape. Use of a GPS camera when recording data from your sample area would allow you to
obtain an aerial photograph of the area from Google earth. Altitude and degree of slope can then be
examined more easily.
Sampling a belt transect involves the area to one or both sides of a transect line being sampled by use
of quadrats. Quadrats are usually 0.5 m2 or 1.0 m2, the size of the quadrat used will determine the
width of the belt transect and the time required to complete data collection. Depending on the nature
of the area being assessed, it is often advisable to record data on one side of the transect line only and
use the other side to move up and down the sample area. This minimises the risk of trampling the
sample area underfoot.
As with a line transect, sampling a belt transect can be:
Continuous – where a quadrat is placed consecutively along the length of a transect line, without gaps.
This can give a lot of detailed information about the density and distribution of species but it is very
time consuming. It is very good for high sites with a high density of species but may repeat similar
results in low diversity areas.
Interrupted – where a quadrat is placed every 1.0 m/1.5 m/2.0 m along the length of the transect line.
This allows the area to be sampled much more quickly and to gather a more manageable volume of
data. The gap between each quadrat sampling point will depend on how long a transect line is being
used and how much time is available to gather data. Clearly, the more quadrats that are recorded along
the length of the transect, the more reliable the data will be of the area being assessed. It should be
noted, however, that this method may miss some less common organisms and may not give a true
representation of trends.
Each species in each quadrat must be recorded for percentage cover of the quadrat. As there may be
many species and they may well overlap each other, it is quite likely that total percentage cover could
be more than 100%.
In order to ensure reliability of results, it is important that the same person records percentage cover in
each quadrat as this estimation is somewhat subjective and by using the same person, you are
reducing this error. Percentage cover of each individual species is much more accurate using a grid
quadrat, where the quadrat area is divided up into small squares of equal area rather than a frame
quadrat.
Apparatus required:
String/measuring tape sufficient for the area of transect. If you are doing an interval or interrupted belt
transect then marking the string with pen every 1.0 m/1.5 m/ 2.0 m greatly speeds up the recording
time.
Suitable keys/ identification guides to allow accurate identification of the species being assessed.
Quadrats 0.5 m2 or 1.0 m2
Sample bags to take back unidentified species (this is done only if there were a high abundance of the
species and would involve the removal of a leaf or two, not the whole plant). Alternatively, digital
photographs can be taken for identification later.
Moisture meter/pH meter /light meter– while line transects focus on ground biodiversity along the
line, it is sensible to take other abiotic factors into account to improve the reliability of your results.
The picture above shows a sampling
site along a belt transect on a shore.
0.5 m2 frame quadrats were being used
and as the vegetation present in the
sampling area was low-lying, both
sides of the transect line were sampled
to increase data reliability.
A belt transect of a grassland slope is shown using
1.0 m2 grid quadrats. If the area contained a lot of
taller herbaceous vegetation or there was a risk of
vegetation being damaged, only one side of the
transect would be sampled.
Note that the results of both quadrats recorded at the
same distance along the transect line are a form of
replication and increase data reliability.
Analysis of results:
Analysis of data obtained should allow the recording of plant and animal species along the length of
the transect. Graphing this data along with light, pH and moisture meter readings along the line will
give a lot of valuable information about the biotic and abiotic factors in the sample area. Displaying
this information graphically allows learners to see clearly whether there is any correlation between
light intensity/ soil moisture level and the abundance of a particular plant or animal species. Further
study into the background of the species found using identification keys and guides should allow valid
conclusions to be drawn.
Record plant species by the use of kite diagrams. Kite diagrams look for patterns of zonation of the
species. For example, if part of the transect line is in the shade, there may be a zone of lower
percentage cover of particular species which increases when the transect reaches an area of increased
light intensity.
Kite diagrams give a useful visual representation of individual species’ cover along a transect. Using
graph paper, begin by marking out the length of the transect to scale along the bottom. On the vertical
axis, draw a horizontal line for the first species you have measured. Allocate an area above and below
the line, which will be the area of the kite diagram for that species. (5 squares in height, above and
below, for example). You then need to mark a vertical bar at each quadrat sampling point along the
transect for the first species (5 bars above and 5 below would mean 100% cover, 4 above and 4 below,
80% cover etc). Then join the tops and bottoms of these bars. If the species was not present at a
particular quadrat sampling, a point should be made on the horizontal line. When you join up the
vertical bars (none of which should be more than 10 squares in height for one species at any sampling
point), you will have a shape that is something like a kite. That is the profile of one species; draw
another horizontal line along the graph paper for the next species measured, and so on.
Species 1
.
0
1
2
3
4
5
6
Length of transect line (metres)
7
8
9
10
.
11
12
13
14
15
16
17
18
It is important that an evaluation of sources of error is carried out. If the whole area being sampled is
very uniform, then data from other groups recording alongside can be used for comparison. Care must
be taken with this, however, as even in a very small area, there can be considerable environmental
variation e.g. presence of a large tree with a lot of canopy cover.
It is also important to remember that overall error can be greatly minimised if learners are familiar
with the equipment and techniques being use.
Unit 2 Learning Activity C: Identification and taxonomy
This Learning Activity supports the following section of the arrangements:
Unit 2 Organisms and Evolution
1 Field techniques for biologists
(c) Identification and taxonomy
The following aspects of the arrangements are supported by these activities:
Identification of a sample can be made using expertise, classification guides, keys or
laboratory analysis of DNA, protein or other molecules
The animal kingdom is divided into phyla, which include … Platyhelminthes (flatworms:
bilateral symmetry, internal organs but no body cavity, many parasitic).
What this learning activity covers
This learning activity is divided into four sections that aim to:
1.
Introduce learners to the taxonomy of the Phylum Platymelminthes through targeted
internet research
2.
Develop skills of learners through observation of freshwater Planaria
3.
Increase learner skills in identification while contributing to the collective knowledge
of the distribution and abundance of an invasive species of Platyhelminth, the New
Zealand flatworm
4.
Allow learners the opportunity to search for and classify parasitic Platyhelminthes (as
well as parasitic Nematodes and Arthropoda) through body cavity dissection of a
member of the Chordata.
While it might be possible to complete this activity over the course of five or six 45-minute
lessons, it could easily be integrated into a longer period of study. For example, this learning
activity is designed to work well in conjunction with the tutorials on sex and virulence
(Tutorial 4) and challenges in treatment and control (Tutorial 5). Learning Activity 2 could be
used to support the fieldwork.
Part 1: Introduction to the Phylum Platymelminthes (tutor notes)
This is intended to be set as an individual homework exercise. It should reinforce the
characteristics of Platyhelminthes required in the arrangements. It also should give learners
the opportunity to interpret and sketch cladograms. The cladogram of relationships within the
Platyhelminthes supports those learners who will also be covering the tutorials mentioned
above.
Part 2: To introduce learners to the Phylum Platymelminthes through observation of
Planaria behaviour (tutor notes)
It would be appropriate to begin this lesson with a brief summary of the homework before
continuing. The object of this lesson is for learners to attempt to observe the defining features
of the Platyhelminthes directly. For this lesson a sample of Planaria are required. These are
easily collected from the bottom of most ponds and streams with a small net and they are easy
to keep in the laboratory for several weeks if necessary. They should be kept in pond water or
bottled spring water in a small plastic tank kept in a darkened area. The Planaria can be fed
with small fragments of raw liver or boiled egg yolk once a week. Any excess should be
removed after an hour or so. Soft paintbrushes can be used to handle Planarians. The water
should be changed every week and the tank scrubbed to remove mucus build-up if the
Planaria are to be maintained for a longer period of time.
Petri dishes, watch glasses, cavity slides and microscopes are required.
Small fragments of boiled egg or liver can be used to stimulate feeding.
3% ethanol can be used to immobilise the Planaria if desired. See the following reference:
Stevenson CG, Beane WS, 2010 A Low Percent Ethanol Method for Immobilizing
Planarians. PLoS ONE 5(12): e15310. doi:10.1371/journal.pone.0015310
The natural regeneration ability of Planaria is of increasing interest to those studying stem
cells. For details on an extension activity to this lesson investigating the regeneration of
planaria see http://www.hhmi.org/biointeractive/activities/
Scroll down and click on the links under “Planaria Regeneration Activity”.
Part 3: To increase learner identification skills while contributing to the collective
knowledge of the distribution and abundance of an invasive species of
Platyhelminth (tutor notes)
This activity gives the opportunity for learners to plan and carry out a small survey for the
invasive New Zealand flatworm in the school or college grounds or equivalent. This would be
a good opportunity for learners to develop a risk assessment, with guidance.
It is recommended that terrestrial flatworm traps (plastic bags, half-filled with soil and placed
on bare soil) are set up by the learners a few days in advance of the survey. Alternatively,
they may choose to use ground yellow mustard and water to bring flatworms and their
earthworm prey to the surface (see “liquid extraction” on this webpage
http://www.nrri.umn.edu/worms/research/methods_worms.html). The latter is a good
alternative in areas where the invasive flatworms are less common.
As the New Zealand flatworm is an invasive species, data on its distribution and abundance in
Scotland is of value. The results of your survey (species, number, postcode of survey
location) should be forwarded to Dr Brian Boag, The James Hutton Institute, Invergowrie,
Dundee DD2 5DA. It is also possible to send samples to Dr Boag to confirm initial
identifications.
Note that if you suspect you have found a New Zealand or Australian flatworm, or their egg
capsule, it is advisable to wear gloves before handling the specimen. In addition, please note
that it is an offence to introduce these species into the wild, so if they are sampled as part of
this activity they cannot be returned to the wild but instead must be destroyed. To destroy any
unwanted flatworms they should be placed in a screw capped container containing either very
salty or very hot water. Alternatively they can be placed in a freezer as they cannot withstand
such low temperatures.
In order to ensure that the flatworms are identified correctly the learners are provided with
resources to establish appropriate identification. Once they have decided upon these let them
see the identification article from the journal British Wildlife (Jones, HD (2005) Identification
of British Land Flatworms British Wildlife 16, 189–194) to see how it compares with their
notes. http://bit.ly/1FdAf1f
Part 4: To search for and classify parasitic Platyhelminthes (and Nematodes and
Arthropoda) through dissection of a member of the Chordata. (tutor notes)
This is a modification of a whole fish dissection activity and all suitable laboratory
precautions should be applied. It is necessary to wear gloves for this activity. Fish waste
should be double bagged prior to disposal.
Whole (ungutted) fish can be bought from a fish counter and need not be large. This could
carried out as a demonstration, group activity or individually.
The activity involves:




examination of the exterior surface, mouth and gills of the fish for ectoparasites
(the operculum covering the gills can be cut away to access the gills more easily)
opening up the body cavity (the coelom) to access the digestive organs
(cut from anus to operculum and then remove one side of the body wall)
examination of the liver
(for parasitic nematodes and flukes in particular)
examination of and flushing of the stomach and intestines with distilled water
(for parasitic nematodes and cestodes in particular).
A recommended outline protocol is available here:
http://www.woodrow.org/teachers/bi/1995/parasite.html
It would be advantageous to ensure that learners have familiarity with basic fish anatomy first
and this would be a useful homework before the lesson. An internet search will reveal many
helpful images such as the one
below.
Schematic drawing of inner anatomy of a teleost (fish) with operculum and side of body removed. 1
liver, 2 stomach, 3 intestine, 4 heart, 5 swim bladder, 6 kidney, 7 testis, 8 ureter, 9 efferent duct, 10
urinary bladder, 11 gills
Learners should become familiar with the types of parasites that they might find using the
following websites.
For illustrations of the parasites try this website: http://thegab.org/Illness-andTreatment/common-freshwater-fish-parasites-pictorial-guides.html
The illustrations on this website can be found in their original documents here:
http://edis.ifas.ufl.edu/topic_series_common_freshwater_fish_parasites
Note that many additional parasites will be visible if scraping samples from the exterior
surface of the fish are mounted on slides for viewing under the light microscope. This would
be a suitable activity to improve microscopy technique for Unit 1.
Part 5: Introduction to the Phylum Platymelminthes
The Phylum Platyhelmithes contains all of the organisms that are known as flatworms. Three
groups of these flatworms are specialist parasites and are thought to form distinct taxonomic
groups – the tapeworms (Cestodes), the flukes (Trematodes) and the monogeneans. The freeliving non-parasitic flatworms are known as the Turbellaria.
The following illustration shows a freshwater Turbellaria, known as a Planarian flatworm.
These are commonly found in ponds and streams and are easily gathered by sampling the
aquatic vegetation or substrate of these habitats.
All of the Platyhelminthes are grouped together because they share features of their body plan
not shared by members of the other animal phyla. Use the following references, make a list of
the features that define the Platyhelminthes.
http://www.biology.iastate.edu/Courses/211L/Platyhelm/%20Platyhelminindx.htm
http://umanitoba.ca/Biology/BIOL1030/Lab1/biolab1_5.html - Turbellaria
The following webpage includes information on the taxonomy of the Beef Tapeworm, which
is one of the Platyhelminthes. Examine the two cladograms found on that page.
http://bioweb.uwlax.edu/bio203/s2009/temanson_caro/Classification.htm
Sketch simplified versions of each of these two cladograms to show the closest relatives to
the Platyhelminthes and the how the four subdivisions of the Platyhelminth phylum are
arranged. Use the labels in the boxes on the right hand side of the web page to help.
Part 6: To introduce learners to the Phylum Platymelminthes through observation of
Planaria behaviour
The aim of this lesson is to improve observation skills through the examination of live freeliving freshwater flatworms.
Planaria are common free-living members of the Platyhelmith phylum. They are easily found
in freshwater environments such as ponds or rivers. In order to observe their behaviour in the
laboratory it is necessary that some should be collected in advance of the lesson. Generally
they are easy to find in among detritus in ponds, rivers or canals. They are easy to keep in a
suitable small aquarium in the laboratory for several weeks until required.
To observe the movement of the flatworms, they should be placed in petri dishes or watch
glasses with a small volume of pond water.
You should already be familiar with the defining characteristics of the Platyhelminthes. The
challenge is to observe as many of these characteristics in the live specimens. The nonsegmented flattened body shape with bilateral symmetry should be noted, as should the
gliding motion. The feeding behaviour can be observed by adding a small amount of liver or
boiled egg yolk. The pharynx acts as both the mouth and the anus.
Internal structures within the living flatworm can be visible under magnification. A small
planarian can be mounted in a cavity slide under the light microscope. Alternatively, a
binocular microscope or hand lens will reveal details not easily distinguished by the naked
eye.
If you want to immobilize a planarian for observation then placing them in a 3% ethanol
solution shortly beforehand is recommended by this paper: Stevenson CG, Beane WS, 2010
A Low Percent Ethanol Method for Immobilizing Planarians. PLoS ONE 5(12): e15310.
doi:10.1371/journal.pone.0015310
Other defining characteristics of the phylum might be more difficult to observe (eg no body
cavity, three layers of tissue). To see these features a planarian would have to be dissected. In
considering the ethics of this procedure it is worth noting that the Planaria are well-known for
their powers of regeneration. For example, Planaria cut longitudinally may regenerate into
two individuals. The following website has a suggested classroom activity aimed
investigating the regenerative powers of Planaria as a model for stem cell action.
http://www.hhmi.org/biointeractive/activities/
Follow the links under “Planaria Regeneration Activity”.
Part 3: To increase learner identification skills while contributing to the collective
knowledge of the distribution and abundance of an invasive species of
Platyhelminth
The New Zealand flatworm is an invasive species of terrestrial turbellarian introduced
accidentally into Scotland through horticultural activities. The New Zealand flatworm is an
efficient predator of earthworms. It reduces earthworm populations to an extent where soil
quality is negatively affected. This affects crop productivity and drainage. See the following
links for more information (if there are several learners in your group, you should share this
task and report to the group):
https://secure.fera.defra.gov.uk/nonnativespecies/index.cfm?sectionid=47
The PDF on New Zealand flatworm listed on the above government webpage should be
downloaded.
http://www.snh.org.uk/publications/on-line/advisorynotes/7/7.htm
Information from Scottish Natural Heritage
http://adlib.everysite.co.uk/adlib/defra/content.aspx?id=000IL3890W.17UT22DO8RW2PJ
Information from Department for Environment, Food and Rural Affairs
http://www.fera.defra.gov.uk/plants/publications/documents/flatwormsCop.pdf
Code of practice to prevent the spread of non-indigenous flatworms
http://www.dgsgardening.btinternet.co.uk/flatworm.htm
A gardening site from Northern Ireland provides a simple to read illustrated summary
http://www.hutton.ac.uk/news/dna-testing-new-zealand-flatworms
New Zealand flatworms and genomics1
Your aim is to design and carry out a survey of part of your school or college grounds (or
gardens, allotments, etc. in your neighbourhood). As this activity involves fieldwork, you
may be involved in the development of an appropriate risk assessment for this activity (see
Unit 2 Learning Activity A: Health and Safety).
As the New Zealand flatworm is an invasive species, data on its distribution and abundance in
Scotland is of value. You can contribute to this body of knowledge by surveying your school
or college grounds (or suitable area eg gardens or allotments) for the presence and abundance
of the New Zealand flatworm or its egg capsules. The flatworms can be found on the soil
surface and will seek damp places, such as under loose turf, plastic or other sheeting, rocks,
flat stones, plant containers etc. Your survey will be more likely to yield results if you set out
some terrestrial flatworm traps in advance. A terrestrial flatworm trap is easily made by
placing a plastic bag half-filled with soil on a patch of bare soil. The flatworms can be looked
for by checking underneath the bag every 3 days for the duration of your survey. It is also
possible to bring flatworms and worms to the surface by pouring a diluted mixture of ground
yellow mustard and water onto a 25 x 25 cm patch of ground (see “liquid extraction” on this
webpage http://www.nrri.umn.edu/worms/research/methods_worms.html). As this latter
technique samples both the invasive predator and the prey it might be a source of useful
ecological data in a wider investigation.
You will also need to ensure that you can identify the flatworms correctly. Use the resources
from the websites listed above to establish appropriate identification criteria for the invasive
New Zealand flatworm.
Note that if you suspect you have found a New Zealand or Australian flatworm, or their egg
capsule, it is advisable to wear gloves before handling the specimen. In addition, please note
that it is an offence to introduce these species into the wild, so if they are sampled as part of
this activity they cannot be returned to the wild but instead must be destroyed. To destroy any
unwanted flatworms they should be placed in a screw-capped container containing either very
salty or very hot water. Alternatively, place them in a freezer, as they cannot withstand such
low temperatures.
The results of your survey (species, number, postcode of survey location) should be
forwarded to Dr Brian Boag, The James Hutton Institute, Invergowrie, Dundee DD2 5DA. It
is also possible to send samples to the same address to confirm initial identifications and for
further research.
Part 4: To search for and classify parasitic Platyhelminthes (and Nematodes and
Arthropoda) through dissection of a member of the Chordata.
This activity involves the dissection of whole (ungutted/uncleaned) fish. These can be
obtained from a fishmonger or similar.
The activity involves:
• an examination of the exterior surface, mouth and gills of the fish for ectoparasites
(the operculum can be cut away to access the gills more easily)
• opening up the body cavity (the coelom) to access the digestive organs
(cut from anus to operculum and then remove one side of the body wall)
• examination of the liver (for parasitic nematodes and flukes in particular)
• examination of and flushing of the stomach and intestines with distilled water (for parasitic
nematodes and cestodes in particular).It is necessary to wear gloves for this activity.
A recommended outline protocol is available here:
http://www.woodrow.org/teachers/bi/1995/parasite.html
Learners should be familiar with basic fish anatomy first before the activity.
For illustrations of the parasites try this website:
http://thegab.org/Illness-and-Treatment/common-freshwater-fish-parasites-pictorialguides.html
The original illustrations on the above website can be found in their original documents here:
http://edis.ifas.ufl.edu/topic_series_common_freshwater_fish_parasiteshttp://edis.ifas.ufl.edu/
topic_series_common_freshwater_fish_parasites
Note that many additional parasites will be visible if scraping samples from the exterior
surface of the fish are mounted on slides for viewing under the light microscope. This would
be a suitable activity to improve microscopy technique for Unit 1.
CfE AH - Unit 2 Learning Activity D: Monitoring Populations (Techniques)
This Learning Activity is intended to support the following Mandatory Key Area:
Unit 2 Organisms and Evolution
1 Field techniques for biologists
(d) Monitoring Populations
The Mandatory Course key area states:
The use of information on species abundance to assess environmental impact. Method of
mark and recapture to estimate population size (N = (MC)/R).
Effective and ethical methods of marking to include banding, tagging, surgical implantation,
painting and hair clipping.
Exemplification of key area:
Presence, absence or abundance of particular species can give information of environmental
qualities, such as presence of pollutant. Classification of vegetation types is based on
indicator species within the community structure.
Mark and recapture is a method for estimating population size. A sample of the population is
captured and marked (M) and released. After an interval of time, a second sample is captured
(C). If some of the individuals in this second sample are recaptures (R) then the total
population N = (MC)/R, assuming that all individuals have an equal chance of capture and
that there is no immigration or emigration.
Methods of marking: The method of marking and subsequent observation must be effective
and should also minimize the impact on the study species.
Mark and Recapture Learning Activity
Background
Mark and recapture is an ecological monitoring technique used to estimate population size. In
static or slow moving species, individuals in a population can possibly counted or estimated
with relative ease by other methods such as use of quadrats. Estimation of fast moving species
or species that are hidden from view requires a more dynamic system.
Typically, a researcher will capture a sample of a population, mark them and then release
them back into the wild. Later, a new sample is captured and the number of marked
individuals counted. As the proportion of the newly caught marked individuals will be
proportional to the number of marked individuals in the whole population then an estimation
of total population size can be made.
While this technique is known to be effective - A mark recapture method was first used for
ecological study in 1896 by C.G.J. Petersen to estimate plaice, Platichthys platessa,
populations, several important considerations must be taken into account:







There is a potential risk of injury to the organism being collected during the
collection process.
The actual marking of the organism could be harmful. If paint of some type is used, it
could possibly be toxic to the organism.
The marking system used has to be able to remain on the organism long enough to be
recaptured. A water soluble mark would not be useful if it rained or was applied to an
aquatic organism!
Being marked could actually mean that the organism is now more visible to predators
and consequently there could be an increased predation of marked individuals which
would affect the overall population estimation.
Are all individuals easy to catch? It depends on the stage of life of the organism in
question or what time of day they are more active. It may depend on abiotic factors
such as moisture level or whether the area is in sunlight or shaded.
Is the population size likely to change significantly during the time of mark and
recapture? Keeping this time short would minimise this.
Most organisms would be expected to be wary or being captured but some may show
no concern and be comfortable about the process. This could skew the type of
organism you are capturing and marking if the marked individuals are not a
representative sample of the population as a whole.
Method: How to estimate a population
One of the most widely known methods of population estimation is the Lincoln-Peterson
method, also known as the Lincoln Index. This method assumes that the population being
estimated is closed. This means that during the time between the two sampling times, no
individuals in the population are expected to have died or been born or moved into or out of
the area being sampled. Obviously no population is ever entirely ‘closed’ but by making the
time interval between the first and second sample time as short as possible, the population
being estimated can be assumed to be closed.
Lincoln Index
M= number of animals first marked and released
C = number of animals captured in the second sample
R= number of marked animals recaptured in the second sample
N = total population
Then N = MC
R
Suggested activities
Live organism mark and recapture:
Depending on the local area, select a small animal e.g. snails or woodlice to be
sampled. Mark a sample of the collected animals with a recognisable spot that would
allow it to be recognised if recaptured but not so large as to make it easily visible to
predators. A small drop of liquid correction fluid would suffice.
Return the marked animals to where they were found. They need to be left long
enough to reintegrate with the rest of the population but not so long that the mark may
be rubbed off or that individuals may enter or leave the population. A day or so would
be sufficient.
Recapture a second sample of the chosen animal and try to estimate the total
population N using the method given above.
Evaluation of results from live organism mark and recapture:
When evaluating the results obtained, it is important to consider whether the trapping
and marking process itself affects whether or not the organism returns to the trap. It
may become very trap tolerant, having survived the process before. If R (number of
marked individuals recaptured) is overestimated due to trap tolerance, N (total
population size) would be lower.
It is also important to consider whether then actual mechanism of marking affects the
number of organisms being recaptured (e.g., due to predation/ organism traumatised
by marking process). If R is reduced, N would be higher than expected.
While planning a learning activity using live organisms is authentic fieldwork, it has
limitations as detailed above. It is also more complex to perform adequate replicates and
repeats of this investigation to allow reliable conclusions to be made. We must also take into
account whether it is necessary to mark live animals in order to evaluate this mark and
recapture method. The following two suggested activities use simulations that are applicable
in the classroom/school to exemplify the mark and recapture method.

Bean/Pea Populations:
Each working pair of learners should be given a sealed box containing a ‘population’
of dried pulses of choice e.g Peas. It does not matter what the total number of the
population actually is, but it is important that the number is known by the teacher.
One learner should remove a small sample of peas to mark (M) and return them to the
box. Marking the peas is best done with a pen rather than sticking tape onto them as
this would allow the marked peas to be easily felt by touch in the box. The box then
needs to be shaken to redistribute the peas. With their eyes closed, the learner needs
to select a handful of peas from the population (C). These need to be checked to see if
any of them were the marked peas that have been recaptured (R). Record this
information and work out N.
Repeat the activity 10 times to check how reliable a value of N is being calculated.
Learners then need to check with the teacher what was the known original number of
the ‘population’ of peas.

Estimating School Population:
Whether it is better to estimate the population of an area of the school or the whole
school will obviously depend on the size of the school. An estimation could be made
of the size of the population in an area of the school at a set time e.g. dining hall at
lunch.
Learners would need to pick some willing volunteers to be the marked sample and
give them a band to wear or put a sticky label onto their uniform. Another learner
who is not aware of who was chosen to mark would then select at random a new
sample of captured individuals (C) and check how many of them were already
marked and therefore recaptured (R).
This activity is not without its limitations. Populations of learners rarely act as a
closed population and tend to move about a lot and this can affect results. You may
also find that the marks are lost or removed by individuals and can be a source of
error.
Further analysis of results of this technique can be made in order to reduce bias. The Schnabel
Method of mark and recapture allows for a less biased estimator of population size.
N = (M +1) (C+1) - 1
R+1
M= number of animals first marked and released
C = number of animals captured in the second sample
R= number of marked animals recaptured in the second sample
N = total population
Sources
1. http://www.offwell.free-online.co.uk/lincoln.htm
2. http://en.wikipedia.org/wiki/Mark_and_recapture
3. Southwood, T.R.E. & Henderson, P. (2000) Ecological Methods, 3rd edn. Blackwell
Science, Oxford
4. Chapman, D.G. (1951). Some properties of the hypergeometric distribution with
applications to zoological sample censuses.
Overview of Section 2 – Organisms
Mandatory Course key area
(SQA Course and Unit Support notes)
(a) Evolution
(i) Drift and selection
Processes of evolution, natural selection, sexual
selection and genetic drift. Mutations can be harmful,
neutral or beneficial and give rise to variation.
Absolute fitness is the ratio of frequencies of a
particular genotype from one generation to the next.
Relative fitness is the ratio of surviving offspring of
one genotype compared with other genotypes.
(ii) Rate of evolution
Where selection pressures are high, the rate of evolution can
be rapid. The rate of evolution can be increased by factors
such as shorter generation times, warmer environments, the
sharing of beneficial DNA sequences between different
lineages through sexual reproduction and horizontal gene
transfer.
(iii) Co-evolution and the Red Queen Hypothesis
A change in the traits of one species acts as a selection
pressure on the other species. Co-evolutionary ‘arms race’
between a parasite and host as an example of the Red Queen
Hypothesis.
(b) Variation and sexual reproduction
(i) Costs and benefits of sexual and asexual reproduction
Disadvantages of sexual reproduction – males unable to
produce offspring, only half of each parent’s genome passed
onto offspring. Benefits outweigh disadvantages due to
increase in genetic variation in the population.
Successful asexual reproduction strategies – to include
examples of vegetative cloning, parthenogenesis and
horizontal gene transfer.
Suggested learning activities
(SQA Course and Unit Support
notes)
Comparison of cladograms of
MRSA and primate evolution to
compare the effect of generation
time on rates of evolution.
Investigate horizontal gene
transfer using X-bacteria.
Read excerpts from Matt Ridley’s
book The Red Queen. Case study
on HIV and CD4 variability or
evolution of Plasmodium
falciparum and P. vivax with
reference to primate evolution.
Consider how the evolutionary
importance of sexual reproduction
influences experimental design in
the life sciences: the natural
variation generated means that
biologists have to take care when
sampling a population and
analysing data to make sure that
they can distinguish this ‘noise’
Education Scotland
Support Materials
Useful video/web links
Unit 2 PPT 1
(Evolution, drift &
selection)
http://www.newscientist.com/topic/evolution
Various up to date articles on evolution as
well as some video clips looking at evidence
for evolution.
Unit 2 PPT 2 (Rate of
Evolution)
Unit 2 PPT 3 (Coevolution & the Red
Queen)
https://www.youtube.com/watch?v=a8GMN
Eg6c6U
3:55 min video explaining the Red Queen
Hypothesis in simple terms.
Unit 2 Tutorial 1 (Coevolution)
Unit 2 PPT 4 (Costs
and Benefits of
Sexual Reproduction)
Unit 2 Tutorial 2
(Costs and Benefits
of Reproduction)
(ii) Meiosis forms variable gametes
Increased variation through the production of haploid
gametes by meiosis - meiosis I, meiosis II, gamete mother
cell, chromosome, chromatid, homologous pairs, crossing
over, chiasmata, independent assortment, linked genes and
frequency of recombination.
In many organisms, gametes are formed directly from the
cells produced by meiosis. In other groups, mitosis may
occur after meiosis to form a haploid organism; gametes
form later by differentiation.
(iii) Sex determination
Sex determination in mammals and Drosophila, sex ratio
and resource availability.
Environmental factors can affect sex determination. Change
of sex through size, competition or parasitic infection.
Hermaphrodites.
Sex linked patterns of inheritance in carrier females and
affected males in terms of gene products.
Random inactivation on X chromosomes in females
prevents a double dose of gene products. Half of the cells in
any tissue will have a working copy of the gene in question
therefore carriers remain unaffected by any deleterious
mutations.
(c) Sex and behaviour
(i) Sexual investment
Comparison of investment in sperm and egg production –
number and energy store; greater investment by females.
Problems and solutions of sex for sessile organisms.
from any experimental result or
‘signal’.
Examine reproduction in a
parthenogenic organism such as
the laboratory stick insect
Carausias morosus (in which
offspring are female) and
compare with the Komodo dragon
(in which offspring are male).
Use microscopy to examine
gamete formation or gametes in
plants or invertebrates.
Breed model organisms in the
laboratory (eg Drosophila or
rapid-cycling Brassica) to
demonstrate independent
assortment or, if possible,
recombination.
Examine data on sex
determination in a variety of
organisms. Research sex-ratio
manipulation in red deer.
Compare the flowers of
hermaphroditic and unisexual
plants.
Use Drosophila to investigate sexlinked inheritance patterns.
Examine data on inheritance
patterns of tortoiseshell cats.
Case study on X linked
agammaglobulinemia and colour
vision defect.
Investigate foraging/pollinating
behaviour of insects at flowers.
Investigate a range of
reproductive strategies using
Unit 2 PPT 5
(Meiosis forms
variable gametes)
http://www.cellsalive.com/meiosis.htm
Unit 2 PPT 6 (Sex
Determination)
https://www.youtube.com/watch?v=NQ4Mh
_CU15E
Animation of Meiosis
15:43 minute Video explaining Sex
Determination in Drosophila.
Unit 2 PPT 7 (Sexual
Investment)
http://academic.reed.edu/biology/professors/
srenn/pages/teaching/web_2006/Mole_Rat_c
d_dtb/reproductive.html
Parental investment, optimal reproduction and reproductive
strategies in terms of the number and quality of current
offspring versus potential future offspring. Classification of
parental investment into discrete r-selected and K-selected
organisms does not reflect continuous range of life history
strategies.
ii) Courtship
Sexual dimorphism as a product of sexual selection.
Male-male rivalry: large size, weaponry, sneakers.
Successful courtship behaviour in birds and fish can be a
result of species-specific sign stimuli and fixed action
pattern responses Imprinting, an irreversible developmental
process that occurs during a critical time period in young
birds, may influence mate choice later in life.
Females are generally inconspicuous, reversed in some
species. Female choice: assessing male fitness, Fitness can
be in terms of good genes and low parasite burden. Lekking
species. In lekking species, alternative successful strategies
of dominant and satellite males.
d) Parasitism
(i) The parasite niche
Parasites tend to have a narrow niche as they have high host
specificity and may lead to parasites which are degenerate.
They are lacking in structures and organs found in other
organisms.
Ectoparasite and endoparasite niches. Life cycles, definitive
hosts, intermediate hosts and vectors.
Fundamental and realised niches, interspecific competition
and competitive exclusion.
(ii) Transmission and virulence
Transmission is the spread of a parasite to a host. Virulence
is the potential of a parasite to cause harm to a host. A
higher rate of transmission is linked to higher virulence.
Factors that increase transmission rates include the
overcrowding of hosts at high density, or mechanisms that
allow the parasite to spread even when infected hosts are
incapacitated. Vectors and waterborne dispersal stages are
examples of the latter.
examples such as naked mole rats.
Naked Mole Rat information website
including reproductive strategies.
Courtship in the field: create an
ethogram observing the ritualised
courtship displays of water birds
such as grebes or ducks.
Courtship in the laboratory:
observe stickleback or Drosophila
courtship; investigate sexual
selection in different Drosophila
varieties.
Research honest signalling in
lekking species.
Unit 2 Activity F
(Courtship)
Research the niche of C. difficile
and the use of faecal transplants.
Unit 2 PPT 8 (The
parasite niche)
.
Unit 2 Tutorial 5
(The parasite niche)
Investigate the spread of a plant
pathogen in a variety of planting
densities and humidities.
Consider the potential
socioeconomic impact of plant
pathogens, such as blight.
http://www.bbc.co.uk/nature/adaptations/Co
urtship_display
Some high quality footage of courtship
displays.
Unit 2 PPT 9
(Transmission &
Virulence)
Unit 2 Tutorial 3 (Sex
&Virulence)
http://www.nhs.uk/news/2012/10October/Pa
ges/Poo-transplants-lead-to-potential-newsuperbug-treatments.aspx
NHS explanation of use of Faecal
transplants to treat C. difficle infections.
http://www.microbiologyonline.org.uk/
Excellent online resource with link to good
quality free resources for your school.
Host behaviour is often exploited and modified by parasites
to maximise transmission. Through the alteration of host
foraging,
movement, sexual behaviour, habitat choice or anti-predator
behaviour, the host behaviour becomes part of the extended
phenotype of the parasite. Parasites also often suppress the
host immune system and modify host size and reproductive
rate in ways that benefit the parasite growth reproduction or
transmission.
The distribution of parasites is not uniform across hosts.
Sexual and asexual phases allow rapid evolution and rapid
build-up of parasite population. The most successful
parasites have efficient modes of transmission and rapid
rates of evolution.
(iii) Immune response to parasites
Non-specific defenses in mammals: physical barriers,
chemical secretions, inflammatory response, phagocytes,
natural killer cells destroying abnormal cells.
Mechanism of specific cellular defenses in mammals:
apoptosis, phagocytosis, T lymphocytes, B lymphocytes and
immunological memory cells.
Epidemiology and herd immunity. The herd immunity
threshold is the density of resistant hosts in the population
required to prevent an epidemic.
Endoparasites and antigenic variation.
(iv) Macroparasitic life cycles
Macroparasites: endoparasitic amoebas, platyhelminths,
nematodes. Ectoparasitic arthropods. Ectoparasitic
Transmission through direct contact, consumption of
secondary hosts or endoparasitic transmission by vectors.
Schistosomiasis and malaria.
(v) Microparasites
Microparasites: viruses and bacteria. Human diseases:
influenza, HIV/AIDS and tuberculosis.
Viral structure and replication. Antigenicity.
Use a statistical test to confirm or
refute the significance of results
of an epidemiological study into
disease.
Activity G (Immune
Response to Parasites
– Non-specific and
specific defences)
Unit 2 PPT 10
(Immune Response to
Parasites –
Epidemiology
onwards)
Consider the ecology, evolution,
reproduction and physiology of a
selected human parasite.
Consider how attempts to disrupt
the lifecycle of Plasmodium in the
control of malaria have resulted in
the loss of apex predators due to
bio-magnification of the
organochloride insecticide DDT.
Investigate the effects of a phage
virus on bacterial growth.
Most of the genome of most
eukaryotic species consists of
mobile or defunct
Unit 2 PPT 11
(Macroparasitic and
Microparasites)
http://jbiol.com/content/8/7/62
Journal of Biology article entitled:
Parasite immunomodulation and
polymorphisms of the immune system
By Rick M Maizels
Suitable search engines for learners to use to
find information for Activity H:
http://www.sciencedirect.com/
Activity H
(Macroparasites vs
Microparasites)
Unit 2 PPT 11
(Macroparasitic and
Microparasites)
http://scholar.google.co.uk/
Suitable search engines for learners to use to
find information for Activity H:
http://www.sciencedirect.com/
Activity H
RNA retroviruses and reverse transcriptase.
(vi) Challenges in treatment and control
Treatment and control of parasites.
Challenges in the design of vaccines and drugs including
rapid antigen change and similarities between host and
parasite metabolism.
Sanitation and vector control: overcrowding, natural
disasters, tropical climates, developing countries, child
mortality.
retrotransposons, which are
thought to have
arisen from retroviruses. Active
retrotransposons form new copies
of themselves to be inserted
elsewhere in the same genome.
The genes responsible for the
variability of vertebrate
antibodies are thought to have
evolved from transposons.
Case study on parasitism and
childhood. Research impact of
parasitism on child mortality rates
in developed and developing
countries. Consider benefits of
intervention programmes in terms
of childhood development and
intelligence. Research the decline
of effectiveness of chemical
treatments over time.
(Macroparasites vs
Microparasites)
Unit 2 Tutorial 4
(Challenges in
Treatment & Control)
http://scholar.google.co.uk/
CfE AH - Unit 2 Learning Activity F: Courtship
This Learning Activity supports the following Mandatory Key Areas:
Unit 2 Organisms and Evolution
2 Organisms
(c) Sex and Behaviour
(iii) Courtship
The Mandatory Course key area states:
Sexual dimorphism as a product of sexual selection.
Male-male rivalry: large size, weaponry, sneakers. Successful courtship behaviour in birds and fish
can be a result of species-specific sign stimuli and fixed action pattern responses.
Imprinting, an irreversible developmental process that occurs during a critical time period in young
birds, may influence mate choice later in life.
Females are generally inconspicuous, reversed in some species. Female choice: assessing male
fitness, Fitness can be in terms of good genes and low parasite burden.
Lekking species. In lekking species, alternative successful strategies of dominant and satellite males.
Exemplification of key area:
Male–male rivalry: large size or weaponry increases access to females through conflict. Alternatively
some males are successful by acting as sneakers.
Female choice: males have more conspicuous markings, structures and behaviours. Females assess
honest signals to assess the fitness of males. Fitness can be in terms of good genes and low parasite
burden.
1 Field techniques for biologists
(e) Measuring and recording animal behaviour
The Mandatory Course key area states:
Ethograms and time sampling to compare the behaviour of different individuals of a species.
Exemplification of key area:
An ethogram of the behaviours shown by a species in a wild context allows the construction of time
budgets.
Measurements such as latency, frequency and duration. The importance of avoiding
anthropomorphism.
Courtship Behaviour Group Research Task
Group task: each person to research and make brief summary notes with examples on the following.
1.
2.
3.
4.
Male-male rivalry and courtship behaviour
Female choice – assessing male fitness
Imprinting behaviour
Lekking species – strategies of the dominant and satellite males
Sources:
1. Male-male rivalry and courtship behaviour
 http://www.bbc.co.uk/nature/adaptations/Courtship_display
Selection of videos showing examples of courtship behaviour.
 http://www.arkive.org/red-deer/cervus-elaphus/video-09d.html
Videos showing red deer male-male rivalry
 http://www.janegoodall.ca/about-chimp-behaviour-social-organization.php
Information about chimpanzee courtship behaviour in a dominance hierarchy
2. Female choice – assessing male fitness
 http://beheco.oxfordjournals.org/content/15/2/239.full
Article from Behavioural Ecology: Female mate assessment and choice behavior
affect the frequency of alternative male mating tactics
Author: Barney Luttbeg
 http://www.medsci.uu.se/digitalAssets/21/21196_3.pdf
Fitness effects of female mate choice: preferred males are detrimental for Drosophila
melanogaster females
Authors: U. FRIBERG & G. ARNQVIST
3. Imprinting behaviour
 http://www.britannica.com/EBchecked/topic/284209/imprinting
 http://www.cerebromente.org.br/n14/experimento/lorenz/index-lorenz.html
Learning Who is Your Mother - The Behavior of Imprinting
Authors: Silivia Helena Cardoso and Renato M.E. Sabbatini
4. Lekking species – strategies of the dominant and satellite males
 http://birding.about.com/od/Bird-Glossary-L-M/g/Lek.htm
Definition of lek.
 http://www.bbc.co.uk/nature/life/Black_Grouse
Videos/Information about the black grouse which exhibits lekking behaviour
 https://www.youtube.com/watch?v=AAXf4UMYnoI
Video showing black grouse lek
The following task could be used to cover both key areas if the following activity is completed:
Courtship in the field: create an ethogram observing the ritualised courtship displays of water birds
such as grebes or ducks.
Measuring and Recording Animal Behaviour Activity
Background:
New terms for learners:
Ethology is the scientific and objective study of animal behaviour, usually with a focus on behaviour
under natural conditions
An ethogram is a catalogue or inventory of behaviours or actions exhibited by an animal used
in ethology.
Activity
http://www.living-links.org/resources/materials-for-teachers/measuring-behaviour-lesson-plan/
This resource includes lesson plan, materials as well as supporting research paper.
Alternative activity
Use the following example as a model for learners to develop their own ethogram & time budget. This
activity could be carried out in the local area or at a wildlife park/zoo.
Example: Ethogram & Time Budget
Sample observations
We observed: Grey Seals at Findhorn Bay
Number
1
2
3
4
5
The following details about each animal we have observed.
Female. She had a pup close by and was nursing just before we started to
observe her
Young male. Was interested in us observing and kept following us along
the beach.
Male? Further out. Appeared to be diving to search for/catch food.
Developing a sample list of behaviours:
Step 1: The ethogram: making a list of behaviours
As you observe the behaviours list them in the left hand column. Do not put them in any order.
Behaviour
Diving/Looking for food
Watching shore
Feeding
Swimming
Playing with pup
Nursing pup
Fighting
Defending territory
Smelling
Code
Time
Percentage
Step 2: Creating categories
Determine the major activities of each animal and label those. Then, reorganise the subcategories
underneath them. For instance, fighting with another male would go under defending territory.
However, some items may be in a category all of their own. For instance: we can only guess at why
the animal might be smelling the air… it could be because it is looking for food or simply smelling. In
this case it is better just to note the action, without any interpretation of what the action is.
Behaviour
Diving/Looking for food
Watching shore
Feeding
Swimming
Playing with pup
Nursing pup
Fighting
Defending territory
Smelling
Add more rows/categories as needed
Code
3
1B
3A
4
2A
2
1A
1
5
Time
Percentage
Step 3: Compiling the time budget
Now observe the three animals for the allotted period of time (5 minutes suggested) each. Write down
the length of time you observe behaviour as it happens. At the end, you will report on the percentages
of time spent in each activity.
Behaviour
Diving/Looking for food
Watching shore
Feeding
Swimming
Playing with pup
Nursing pup
Fighting
Defending territory
Smelling
Total Minutes
Code
3
1B
3A
4
2A
2
1A
1
5
Time
3
2
1
4
2
0
1
1
1
15 mins
Percentage
20
13.3
6.7
26.7
13.3
0
6.7
6.7
6.7
Step 4: Generating a chart
1. For each behaviour category, add the total time from each observation together for all
animals, to get a total time for that behaviour.
2. Divide the total time by behaviour by the total time observed and multiply by 100%. This will
give you the percentage of time spent doing that activity.
3. Generate a pie chart, label it and add it to your report like the one below.
CfE AH - Unit 2 Learning Activity G: Immune Response to Parasites
This Learning Activity is intended to support the following Mandatory Key Areas:
Unit 2 Organisms and Evolution
2 Organisms
(d) Parasitism
(iii) Immune Response to Parasites
The Mandatory Course key area states:
Non-specific defences in mammals: physical barriers, chemical secretions, inflammatory response,
phagocytes, natural killer cells destroying abnormal cells.
Mechanism of specific cellular defences in mammals: apoptosis, phagocytosis, T lymphocytes, B
lymphocytes and immunological memory cells.
Epidemiology and herd immunity. The herd immunity threshold is the density of resistant hosts in the
population required to prevent an epidemic.
Endoparasites and antigenic variation.
Exemplification of key area:
Specific cellular defence in mammals involves immune surveillance by white blood cells, clonal
selection of T lymphocytes, T lymphocytes targeting immune response and destroying infected cells by
inducing apoptosis, phagocytes presenting antigens to B lymphocytes, the clonal selection of B
lymphocytes, production of specific antibody by B lymphocyte clones, long term survival of some
members of T and B lymphocyte clones to act as immunological memory cells.
Epidemiology is the study of the outbreak and spread of infectious disease.
Endoparasites mimic host antigens to evade detection by the immune system, and modify host-immune
response to reduce their chances of destruction.
Antigenic variation in some parasites allows them to evolve fast enough for them to be one step ahead
of host immune cell clonal selection.
Immune Response to Parasites Self Study Task
This task covers: Non-specific defences in mammals: physical barriers, chemical secretions,
inflammatory response, phagocytes, natural killer cells destroying abnormal cells.
Mechanism of specific cellular defences in mammals: apoptosis, phagocytosis, T lymphocytes, B
lymphocytes and immunological memory cells.
Immune Response to Parasites Self Study Task
Use the videos from https://www.khanacademy.org/science/biology/human-biology/immunology to
help you study the following and answer the following questions:
Non-specific defences in mammals: physical barriers, chemical secretions, inflammatory response,
phagocytes, natural killer cells destroying abnormal cells.
1.
How are epithelial cells an example of
a physical defence?
2.
Name one chemical defence that
epithelial cells can secrete.
3.
Describe
the
stages
of
the
inflammatory response.
4.
Mast cells produce histamine; describe
histamines effect on blood capillaries.
5.
What chemical attracts phagocytes to
the site of infection?
6.
7.
8.
9.
10.
11.
In
later
stages
of
infection
antimicrobial proteins and clotting agents are produced – how do these aid tissue healing?
Describe the action of phagocytosis on
an invading parasite.
Natural Killer cells are another
example of a non-specific defence – how do they differ in their action to a phagocyte?
What is the correct term for
programmed cell death?
Why would NK and phagocytes be
described as a non-specific cellular response rather than physical or chemical responses?
Using your understanding of the
immune system so far, describe what would happen if you cut your hand while gardening
(assuming your hands are not clean).
Mechanism of specific cellular defences in mammals: apoptosis, phagocytosis, T lymphocytes, B
lymphocytes and immunological memory cells.
1.
Name the chemical which damaged or
invaded cells release to attract white blood cells.
2.
How does a clonal population of
lymphocytes form?
3.
4.
5.
6.
7.
“Failure in regulation of the immune
system leads to a T lymphocyte immune response to self cells” – what is this more commonly
called?
What is an antigen-presenting cell?
How do cytotoxic T Cells act in the
immune response?
T helper cells cannot destroy
pathogens on their own, how do they work to destroy them?
Name the type of cells that produce
antibodies. What are antibodies made of?
8.
Describe the action of antibodies on
antigens.
9.
Why
is
immunological
memory
useful?
10.
Using your understanding of the
immune system so far, how would you design the perfect vaccine?
CfE AH - Unit 2 Learning Activity H: Macroparasites & Microparasites
This Learning Activity is intended to support the following Mandatory Key Areas:
Unit 2 Organisms and Evolution
2 Organisms
(d) Parasitism
(iv) Macroparasitic Life Cycles and (v) Microparasites
The Mandatory Course key area states:
Macroparasites: endoparasitic amoebas, platyhelminths, nematodes. Ectoparasitic arthropods.
Ectoparasitic Transmission through direct contact, consumption of secondary hosts or endoparasitic
transmission by vectors. Schistosomiasis and malaria.
Microparasites: viruses and bacteria. Human diseases: influenza, HIV/AIDS and tuberculosis.
Viral structure and replication. Antigenicity.
RNA retroviruses and reverse transcriptase.
Exemplification of key area:
Ectoparasites and endoparasites of the main body cavities, such as the gut, are generally transmitted
by direct contact or through consumption of secondary hosts. Endoparasites of the body tissues are
often transmitted by vectors.
Schistosomiasis and malaria as examples of human diseases caused by a macroparasites.
Viruses are infectious agents that can only replicate inside a host cell. Viruses contain genetic
material in the form of DNA or RNA, packaged in a protective protein coat.
Some viruses have a lipid membrane surround derived from host cell materials. The outer surface of a
virus contains antigens that a host cell may or may not be able to detect as foreign.
RNA retroviruses use the enzyme reverse transcriptase to form DNA, which is then inserted into the
genome of the host cell. This virus gene forms new viral particles when transcribed.
Macroparasites and Microparasites Research & Presentation Group Task
This activity should follow the Unit 2 PPT 11 which introduces macroparasites and microparasites to
the learners.
Each learner in the class should be allocated one of the following tasks that will lead to them
presenting information to the class. This could be completed as an individual/paired or small group
task depending on number of learners.
Topics: Choose one of the following macroparasites or microparasites to research.
Macroparasites:
1. Platyhelminth - intestinal fluke Metagonimus or tapeworm Cestoda.
2. Schistosoma parasitic worm that causes Schistosomiasis
3. Plasmodium parasite that causes malaria.
Microparasites:
1. Influenza virus
2. HIV
3. Mycobacterium tubercuolosis which causes tuberculosis (TB).
Products:
1. An information poster that will be displayed within the school – this must make the information
that you discover accessible to the majority of learners.
2. A 5-10 minute presentation including all the relevant points about your topic. As well as making it
relevant in regards expected curriculum, the presentation should show evidence of further research.
Presentations to include – a visual presentation (PowerPoint/Prezi presentation/video/animation) with
an informative talk (lasting at least 5 minutes but not more than 10 minutes) that MUST NOT just
repeat what is on your visual presentation. It is expected that it will be understood by AH learners and
teachers but not necessarily younger learners.
3. A summary sheet of the key points to hand out to the rest of the class.
Expectations:
You must research your topic using class resources but also journals and the internet to find out new
and interesting information.
All presentations should include:







Epidemiology: Is the parasite a world-wide phenomenon or endemic to specific countries?
Effect on mortality rates in children and adults
Transmission method – is a vector involved? More than one host organism?
Life Cycle of chosen parasite
Symptoms of disease – including short and potential long term effects
Prevention methods – including sanitation and vector control, prophylaxis, education
Treatment methods
Additional questions for specific topics:
Macroparasites:
1. Platyhelminth - intestinal fluke Metagonimus or tapeworm Cestoda.
 Describe how some types of parasitic gut worm are used as a therapy to treat autoimmune
disorders.
 Is the parasite you have studied likely to be used in this manner? If not, explain why.
2. Schistosoma parasitic worm that causes Schistosomiasis
 Explain why Schistosomiasis can be described as a “Neglected Tropical Disease”.
 What social, economic and health impacts does this have on the countries affected by
Schistosomiasis?
 What is being done about it?
3. Plasmodium parasite that causes malaria
 DDT is an insecticide that was commonly used to control mosquitos - describe the effect
of bio-magnification of DDT within the food chain on the apex predator.
 Drug resistance is becoming an issue with malaria – explain what this means, how strains
of Plasmodium can have appeared that are drug resistant and what scientists are currently
doing to trying to combat drug resistant malaria.
Microparasites:
1. Influenza virus
 Describe some of the historical influenza pandemics such as the 1918 Spanish Flu
Pandemic and its impact on the world population.
 Explain why patients have to be given an Influenza vaccine annually.
 How likely is a flu pandemic now?
2. HIV
 Explain how a retrovirus replicates.
 Describe the origins of HIV.
 Recent studies have suggested that HIV is mutating – what effect is this having on the
virus?
3. Mycobacterium tubercuolosis which causes tuberculosis (TB)
 Why are teenagers no longer vaccinated against TB?
 The World Health Organization declared TB a "global health emergency" in 1993. In
2006, the Stop TB Partnership developed a Global Plan to Stop Tuberculosis. Find out
what their targets were, whether they have been achieved and what they are going to do
next.
Feedback will be provided on your presentations.
Tips for your presentations:



Diagrams/pictures are helpful
Do not have too much writing on the poster or on the screen – keep it to key information and
keep it clear and easy to read
Diagrams and pictures must be attributed and copyright free – try using Creative Commons to
find images.
As you are also to give a talk along with your visual presentation here are some hints:




Break up the information to allow all members of group to contribute
Practise giving the talk to your group to help you gain confidence
Practise projecting your voice enough to be heard in the classroom
When talking to the class you can use notes but do not just read from your notes, make eye
contact with the audience.
Summary sheet:



Should include the key points from your visual presentation and from your talk
This is to help others study and learn so make sure it is clear and easy to understand
Provide links to other sources in case learners want to find out more.