The ASAB book Animal Behaviour Practicals, edited by P. Monaghan and A. K. Turner, is no longer available, but some of the practicals are available here for members to use.
Animal Behaviour Laboratories from Monaghan & Turner
1.1. Insect Grooming Behaviour
In this practical the various components of grooming behaviour are recorded and compared for different species of insects. The students can investigate for themselves the organization of grooming behaviour, and try to answer questions such as: are all preening movements performed with the same frequency; do particular elements tend to precede or follow one another; do grooming bouts always start or end with the same preening pattern; do grooming bouts tend to contain an odd or equal number of acts; and what is the function of grooming? A simple experiment tests the obvious hypothesis that grooming functions to clean the animal.
Materials Needed
For each pair of students, a supply of two or three different insects such as blowflies, cockroaches or cottonstainers; petri dishes each containing one insect to serve as observation chambers; stopwatch; chalk dust.
Suggested Methods
Take three or four blowflies in their observation chambers and watch for one to start grooming. Make notes on the preening movements and illustrate them with diagrams.
Repeat the observations on a further three blowflies and on four individuals of the other species of insect, noting any differences in behaviour.
Decide on the categories of behaviour and units of grooming behaviour to be recorded and devise a scoring method. Ten or more may be recognized in blowflies.
Return to a blowfly, watch it for 15 min and record the total time it spends grooming. Note the number of times each unit of grooming behaviour is performed and the order in which they happen. Also note when there are any breaks in the grooming sequence, if the fly remains stationary or starts walking for example. Use abbreviations for the behaviour patterns to make recording easier. Repeat this procedure on four different blowflies. Label the petri dish so that the fly can be recognized. To analyse the data combine the results for all four flies.
To see whether a particular act is more likely to follow another than to occur at random draw up a transition matrix. Simple inspection of the matrix should reveal if particular transitions are more common than others.
| |
|
Preceding |
|
| |
No grooming |
Front leg grooming |
Head grooming, etc |
| Following |
|
|
|
|
No grooming |
X |
2 |
0 |
|
Front legs |
4 |
X |
45 |
| Head |
0 |
32 |
X |
There are no values on the diagonals because the switch from one behaviour to another is used to define the end of a particular pattern. Therefore ‘No grooming’ cannot follow ‘No grooming’, etc. Class data can be pooled to give a larger sample.
To see how being in a dirty environment affects the grooming behaviour of the insects, place a little chalk dust into the petri dishes containing the four original blowflies. Repeat the measurements made in 4. Compare the proportion of time spent grooming by the clean and dirty flies using a Mann-Whitney U-test (class results can be combined to give a larger sample, but the results are usually very clearcut). Use a chi-squared test to compare the frequencies of the various grooming elements in the four clean and four dirty flies.
Expected Behaviour
The following are some of the behaviour patterns that should be seen in blowflies:
Prothoracic legs together
Prothoracic legs on head
Prothoracic legs plus one mesothoracic leg (left or right)
Metathoracic legs together
Metathoracic legs under abdomen
Metathoracic legs over abdomen
Metathoracic legs under wings
Metathoracic legs plus one mesothoracic leg
Dirty flies groom more than clean ones.
Additional Comments
The experiments are best done in pairs so that one student makes the observations and the other records them. This is generally a very reliable practical.
References
Dawkins, R. & Dawkins, M. 1976. Hierarchical organization and postural facilitation: rules for grooming in flies. Anim. Behav., 24, 739-755.
Lefebvre, L. 1981. Grooming in crickets: timing and hierarchical organisation. Anim. Behav., 29, 973-984.
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1.2 Courtship Behaviour
In this set of practicals, visual displays are described and analysed. Guppies, fruitflies and/or zebra finches can be used. Genetic effects and the existence of reproductive isolating mechanisms can be studied by using different strains of fruitflies. As rapid sequences of behaviour can be difficult to follow, it may help either to video the behaviour or to use cassette tape recorders to note down the behaviour as it happens. In each practical, the interactions between males or between females can be compared with those between males and females (but avoid actual contact if physical aggression is likely). Although the practicals concentrate on visual displays, students can note other channels of communication used by the animals.
GUPPIES
Materials Needed
Choose wild type guppies if possible. Wild type males are relatively small (20 - 30 mm total length) and lack the elaborate finage and colour patterns of the more inbred domestic strains. There should be at least four male and four female guppies for each group of students. The guppies should be housed in tanks with good aeration and filtration. If possible the fish should be moved to the site of the practical several days before it is scheduled to take place. Each group of students should have its own aquarium screened off and kept as free from disturbance as possible.
If virgin females are also available a more interesting practical is possible. The easiest way to obtain virgins is to raise batches of immature fish and remove males as soon as the gonopodium begins to develop or any colour appears. (The gonopodium is a modified anal fin, serving as an intromittent organ during copulation).
Suggested Methods
Net four males and four females from their home tank and put them in the observation aquarium. The females should vary in size from small to large. It is essential that all fish handling is as gentle as possible so it is a good idea to put a qualified technician or demonstrator in charge of this aspect of the practical. The water temperature in the observation tank must be identical to that in the home tank. Allow the guppies to settle in their new tank for 30 min. During this time the observers should quietly watch the guppies and note or draw the individual characteristics of each fish. Males can easily be distinguished from their colour patterns but females can often only be separated in terms of relative size.
The duration of sigmoid displays, along with the frequency of sigmoid displays and sneaky mating attempts, should be recorded for each male for 10 minutes. The number of displays and thrusts directed at each female should also be scored. The females should then be (gently) returned to their home tank.
The observations should be repeated using virgin females. If no virgin females are available a new batch of females from the home tank can be used instead.
Expected Results
Male guppies have two main methods of obtaining a mating. They may perform a Sigmoid Display in which the body is held in an S-shape while the fins are extended and quivered. The male often leaps away by as much as 10 cm. A full sigmoid display lasts for several seconds. Alternatively, males may attempt a Sneaky Mating in which the female is approached sideways or from behind and the gonopodium is thrust towards her genital pore. Females are sexually receptive only as virgins or for a few hours once a month following the birth of a brood. Most non-virgin females ignore male displays and try to avoid sneaky mating attempts. Receptive females respond to a male’s advances by Gliding towards him. Copulation is accompanied by Arching (in which the female moves close to the male, halts and raises her head and tail slightly) and Wheeling (in which both move round in a tight circle). When it is completed the male often jerks away and may cease sexual activity for 30 min or so. Baerends et al. (1955) and Liley (1966) provide a full description of guppy courtship behaviour.
Some Questions to Answer
Do all males use both mating tactics or are there individual differences?
Do males court all females equally or are some females preferred?
Are virgin females equally responsive to all males? Do virgin females become more or less choosy a few hours after their first copulation (see Houde & Endler 1990)?
Does male behaviour change in the presence of virgin females?
Is male behaviour or colour pattern more important in female choice?
Further Reading
Baerends, G., Brouwer, R. & Waterbolk, H.T.J. 1955. Ethological studies on Lebistes reticulatus. 1. Analysis of the male courtship pattern. Behav., 8, 249-334.
Houde, A.E. 1988. The effect of female choice and male-male competition on the mating success of male guppies. Anim. Behav., 36, 888-896.
Houde, A.E. & Endler, J.A. 1990. Correlated evolution of female mating preferences and male color patterns in the guppy, Poecilia reticulata. Science, 248, 1405 - 1408.
Liley, N.R. 1966. Ethological isolating mechanisms in four sympatric species of poeciliid fishes. Behav. Suppl., 13, 1-197.
Liley, P.H. & Liley, N.R. 1985. Geographic variation in the sexual behaviour of the guppy, Poecilia reticulata (Peters). Behav., 95, 164-197.
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