Claire Detrain
Ph D in Zoological Sciences
Research
Associate at the Belgian National Foundation for Scientific Research
Laboratoire de biologie
animale et cellulaire - Unit of Social Ecology CP 160/12
University of Brussels
Avenue F. Roosevelt 50,
B-1050 Bruxelles ; Belgique
Tel. : + 32.(0)2. 650.26.49 Fax. : + 32.(0)2. 650.24.45
e-mail : cdetrain@ulb.ac.be
Pour la version française , cliquez sur la fourmi 
Fields of Research
Information Processing and
Decision-making in Ant Societies
Division of Labour and Social Organization
All these
research topics are available for Doctoral and Post-doctoral Fellowships.
Information Processing and Decision-Making in Ant Societies
Worker of Lasius niger drinking at a droplet of
sugar solution. Drawing:
A.C. Mailleux
Like the hive, the ant nest
is the archetype of animal society.
Its efficient social organization is not based on the “Knowledge” of one
individual (e.g. the queen) which
must take decisions and collect all pertinent information. Instead, an alternative method is used:
problems are collectively solved through the behaviour of the individuals,
which interact with each other and with the environment. Collective structures emerge from
multiple individual decisions based on rules of thumb and coupled to amplifying
phenomena such as trail recruitment. Such collective problem-solving is found
for a wide range of activities
such brood care, brood sorting, foraging, defense,…
To understand how collective
structures emerge, we have thus to investiguate behavioural rules and
decision-making at the individual level. The impressive amount of research
dealing with the function and adaptive value of collective behaviour in insects
might have led researchers to conclude that there is nothing really new to know
about insect societies. But, the individual and collective management of
information as well as its integration into a coherent system are questions
still under debate
Some studied
Questions
+ How does a scout inform
nestmates about environmental ressources and constraints ?
+ Does an ant precisely “measure”
all food characteristics or only assess
few relevant cues ?
+ What is the adaptive value of
recruitment rules followed by ants?
+ How can the environment
contribute to the building-up of collective patterns?
For
more information,
Ph D Thesis: Anne-Catherine Mailleux (2001)
Cédric Devigne, Stéphane Portha (ongoing)
Publications :
see N° 8, 16, 17, 20, 23, 24, 25
Chemical communication
.
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Sting apparatus of the ant Pheidole pallidula.
Secretions from exocrine glands
associated to the sting (poison gland and Dufour gland) are involved in communication
during foraging or nest defense.
Photo
SEM : C. Detrain
Communication
in ants is mainly based on the emission and perception of chemical
compounds. For instance, as a new
resource is discovered by a scout, it lays a trail pheromone that elicits the
mobilization and orientation of nestmates towards food location. Faced with intruders or competitors,
ants can emit alarm pheromones as well as defensive secretions that contain
toxic, irritating or repulsive compounds.
Morphological studies of exocrine glands coupled with
chemical analyses of their content improve our knowledge about the physiology
of social communication in ants.
Beside the discovery of new natural compounds, chemical identification
of pheromones and defensive substances provides taxonomic tools that are highly
useful to discriminate closely related species.
Some
studied Questions
+ Which glands
produce trail pheromones and defensive compounds? What is their chemical composition?
+ Are trail pheromones
species-specific? Can they be
perceived and followed by social parasites to locate the ant nest ?
+ In polymorphic ant species, are castes specialized in the production
or response to pheromones and defensive compounds ?
+ Can we build up a model that describes
orientation and trail-following behaviour of ants ?
For
more information,
Ph D Thesis: Claire Detrain (1989), Ana Hérédia
(2002)
Publications : see N°1, 5, 7, 9, 10, 11, 12, 13
Ant-Plant
Relationships
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|
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Study site of harvester
ants
Messor
barbarus worker carrying an oat seed in its mandibles
Photos: C. Detrain
Like other hymenopterans,
ants can act, directly or indirectly, upon plant community. By eating seeds, harvester ants can
substantially reduce the reproductive success of several Mediterranean plant
species. But, by carrying seeds
and storing them inside the nest, those harvester ants can favour plant
dispersal over long distances, far from the mother plant.
Ants which are not harvester
species can also influence the spatial distribution of some plant species.
Indeed, these ants can occasionally forage on seeds that bear an
elaoisome. This elaiosome is a
fatty corpuscle that is highly attractive to ants that try to feed
on. After carring the seeds back
to the nest, they chew off the elaiosome and remove the remaining part of the
seed outside the nest. As this
part of the seed is still able to
germinate, ants have indirectly contribute to the dispersal of those plant
species.
Some studied Questions
+ What is the impact of the Mediterranean harvester ant,
Messor barbarus, on its biotope?
+ Which seed features influence their retrieval by
harvester ants?
+ How do castes contribute to food
recruitment and seed retrieval in harvester ants ?
+ How non-harvester ants contribute to the
dispersal of seeds bearing elaiosomes (the study case Lasius niger-Viola odorata)?
For more information,
Ph D Thesis: Ana Hérédia
Publications : see N° 18, 19, 21, 22
Division of Labour and Social Organization
Minor
and major worker of the dimorphic
ant Pheidole pallidula (Photo C. Detrain)
Workers
of some ant species are polymorphic and differ in their size as well as in the
relative development of some body parts (e.g. enlarged mandibles, head,…) These physical castes are often
specialized and perform a limited subset of tasks. The ecological success of ant societies relies on an
efficient division of labour between these subgroups of specialized
workers. Caste polyethism results either from qualitative
differences in their behavioural repertoire or from quantitative differences in
their rate of task performance and response thresholds.
In litterature, majors are
often called soldiers as they possess powerful mandibles and are frequently
involved in nest defense. Minors, so-called workers, carry out most of tasks within the nest. But, suhc
division of labour is not a general rule as majors of several ant species can
actively participate into brood care and foraging activities.
Besides, the spatial
distribution of castes over the foraging range and within the nest deeply shape the social organisation of
ants. The spatial location of one
caste will influence the type and rate of stimuli perceived and hence wil
determine the tasks to be performed and the functional specalization of this
caste.
Some studied
Questions
+ Do behavioural repertoires differ between castes in the
polymorphic ants Pheidole
pallidula and Messor
barbarus ?
+ Do response thresholds differ between
castes ? Can we relate differences in response thresholds to division of
labour within the colony ?
+ Are Pheidole pallidula majors
specialized in nest defense or do they contribute to inside nest
activities such as brood care?
+
Do castes differ in their aggregation patterns ? Does it explain their spatial
distribution inside the nest and hence their task specialization ?
For more information,
PhD Thesis : Claire Detrain
(1989)
Grégory
Sempo (ongoing)
Publications : see references
N° 2, 3, 4, 6 , 8, 15
Prospect of technological applications 
Networks Management
Management and Control
of Animal Societies
Networks Management
In insect societies, collective
problem solving results from multiple interactions between individuals that are
based on local information and follow rules of thumb. This collective or so-called swarm intelligence has proved
its efficiency in ants or bees.
Those principles can be transposed to solve problems faced by the
industry or the agriculture.
Swarm intelligence has inspired
specialists in the field of telecommunications. Telephone or internet networks undergo unforeseen
fluctuations and saturation at node points. These flows of information can be managed by a bio-inspired
system where agents “lay virtual pheromones” (in this case, bits of
information). As for ants’ trails,
the interplay between reinforcement and evaporation of those “virtual
pheromones” allows to redirect telephone calls and to prevent saturation of
network nodes.
Swarm intelligence provide an
alternative to traditional robotics in which all agents are pre-programmed and
controlled by a central unit. Indeed, a “society” of several mobile robots can work independently of any centralized
control, by interacting and following rather simple behavioural
algorithms. These ant
inspired-robots are highly effcicient to solve unforeseen in hostile and
everchanging environments. Some
applications to be developed are the exploration of unknown areas (planet, sea
depths,…), security control of storage areas or management of animal societies
(see further section).
Management and Control of Animal Societies
Most
animals of economical importance are social or at least gregarious
species. Societies of mobile
robots that interact and co-operate with animals open new solutions to some
agricultural challenges. For
instance, to remain economically competitive, producers have to reach minimun level of response (e.g.
minimum feeding rate) in their stock farm. Such response rate could be more easily reached and
artificially maintained by sevarel decoy robots that stimulate animals to feed
on. Moreover, as each robot interact only with spatially close animals, several
robots scatter over the breeding area can enhance the feeding synchronizattion
of the whole animal husbandry.
A group
of robots can also prevent the occurrence of unwanted collective behaviour such as panic phenomena. The presence of several robots that
display normal or quietiening behaviour under all circumstances, could counteract
the amplification of local panic behaviour and then prevent their contagion to
the whole farm stock.
Societies
of interacting robots that follow ant-like behavioural rules show interesting
properties of robustness, reliability, flexibility and adaptation to changing
and unpredictible environment. In
the near future, the creation of mixed societies of robots and animals is an
innovative means to anchor in the real-world a synergy between ethology and robotics
but also opens the way to new farming techniques respecting animal welfare.
INFORMATION
PROCESSING IN SOCIAL INSECTS.
Edited by Detrain C., Deneubourg J.L. and Pasteels J.M. 1999, 432 pages. Hardcover . ISBN 3-7643-5792-4
Birkhauser Verlag - Postfach 133 CH-4010 Basel/Switzerland.
About this book: Studies on social insects have been pioneering
in major fields of modern biology.
In the 1970s, research on pheromonal communication in insects gave birth
to the discipline of chemical ecology and provided a scientific frame to extend
this approach to other animal groups.
In the 1980s, the theory of kin selection which was initially formulated
by Hamilton to explain the rise of eusociality in insects, exploded into a
field of research on its own and found applications in the understanding of
community structures including vertebrate ones. In the same manner, recent
studies presented in this book, which decipher collective behaviour of insect
societies, might be now setting the stage for the elucidation of information
processing in animals.
Publications - Claire Detrain
-1- (Z,E)-alpha-farnesene, main constituent of the
hypertrophied Dufour gland of the majors of Pheidole pallidula (Formicidae).
Detrain C., Pasteels J.M., Braekman J.C. and Daloze D.
Experientia, 43 (1987), 345-346.
- 2 - Field study on foraging by the polymorphic ant Pheidole
pallidula.
Detrain C.
Insectes Sociaux, 37 (4) (1990), 315-332.
- 3 - Caste differences in behavioral
thresholds as a basis for polyethism during food recruitment in the ant Pheidole
pallidula.
Detrain C. and Pasteels J.M.
J. Insect Behavior, 4(2), (1991), 157-177.
- 4 - Dynamics of collective exploration
in the ant Pheidole pallidula.
Detrain C., Deneubourg J.L., Goss S. and Quinet Y.
Psyche, 98(1), (1991), 21-31.
- 5 - A new pheromone in the ant Pheidole
pallidula.
Detrain C. and Cammaerts M.C.
Behavioural Processes, 24, (1991), 123-132.
- 6 - Caste polyethism and Collective
defense in the ant Pheidole pallidula: the outcome of quantitative
differences in recruitment.
Detrain C. and Pasteels J.M.
Behavioral Ecology and Sociobiology, 29,(1992), 405-412.
- 7 - A model for osmotropotactic
orientation.
Calenbuhr V., Chrétien L., Deneubourg J.L. and Detrain C.
Journal of theoretical biology, 158, (1992), 395-407.
- 8 - Scavenging by Pheidole pallidula
: a key for understanding decision-making systems in ants.
Detrain C. and Deneubourg J.L.
Animal Behaviour, 53, (1997), 537-547.
- 9 - Identification of a component of the
trail pheromone of the ant Pheidole pallidula.
Ali M.F., Morgan E.D., Detrain C. and Attygale A.B.
Physiological Entomology, 13 (1988), 257-265
- 10 - Host-trail following by the
myrmecophilous beetle Edaphopaussus favieri (Fairmaire, Carabidae, Paussinae).
Cammaerts R., Detrain C. and Cammaerts M.C.
Insectes Sociaux, 37(3) (1990), 200-211.
- 11 - Chemical defense in the three
European species of Crematogaster ants.
Daloze D., Kaisin M., Detrain C. and Pasteels J.M.
Experientia, 47 (10), (1991), 1082-1088.
- 12 - Host trail-following by the guest
ant Formicoxenus provancheri (Hymenoptera, Formicidae).
Lenoir A., Detrain C. and Barbazanges N.
Experientia, 48, (1992), 95-97.
- 13 - Venom constituents of three species
of Crematogaster ants from Papua New Guinea.
Leclercq S., Braekman J.C., Kaisin M. Daloze D., Detrain C., de Biseau J.C.,
Pasteels J.M.
Journal of Natural Products, 60 (11), (1997), 1143-1147.
- 14 - The dynamics of collective sorting
robot-like ants and ant-like robots.
Deneubourg J.L., Goss S., Franks N., Sendova-Franks A., Detrain C. and Chrétien
L.
In: Simulation of adaptive behavior: from animals to animats. Meyer J.A.
and Wilson S (eds), MIT Press, (1991), 356-365.
- 15 - Lipid storage by major workers and
starvation resistance in the ant Pheidole pallidula.
Lachaud J.P., Passera L., Grimal A., Detrain C. and Beugnon G.
In: Biology and Evolution of Social Insects, Billen J (ed), Leuven
University Press, Leuven (Belgium), (1992), 153-160.
- 16 - Decision-making in foraging by
social insects
Detrain C., Deneubourg J.L. et J.M. Pasteels
In: Information processing in social insects. Detrain C.,
Deneubourg J.L. et J.M. Pasteels (eds), Birkhauser Verlag (1999),
331-354.
- 17 - Self-organization or individual
complexity: a false dilemna or a true complementarity
Deneubourg J.L., Camazine S. and Detrain C.
In: Information processing in social insects. Detrain C.,
Deneubourg J.L. et J.M. Pasteels (eds), Birkhauser Verlag (1999), 401-408.
- 18 - Seed preferences of the harvester
ant Messor barbarus in a Mediterranean mosaic grassland
Detrain C. and Pasteels J.M.
Sociobiology 35, (2000), 35-48
- 19 - A field assessment of optimal
foraging in ants: trail patterns and seed retrieval by the European harvester
ant Messor barbarus.
Detrain C., Tasse O., Versaen M. and Pasteels J.M.
Insectes sociaux 47, (2000), 56-62.
- 20
- How do the ants assess food volume?
Mailleux A.C., Deneubourg J.L. and Detrain C.
Animal behaviour 59, (2000), 1061-1069.
- 21
- Seed drops and caches by the harvester ant
Messor barbarus: do they contribute to seed dispersal in Mediterranean
grasslands?
Detrain C. and Tasse O
Naturwissenschaften, 87, (2000), 373-376
- 22 - Worker size polymorphism and
ethological role of abdominal exocrine glands in the harvester ant Messor
barbarus.
Heredia A. and Detrain C.
Insectes Sociaux 47, (2000), 383-389.
- 23 - The influence of the physical environment on the
self-organised foraging patterns of ants
Detrain C., Natan C. and Deneubourg J.L.
Naturwissenschaften
88, (2001), 171-174.
- 24 - Plan d’organisation et population dans les sociétés d’insectes
Deneubourg
J.L., Millor J., Theraulaz G. and Detrain C.
In: L’homme
devant l’incertain. Odile Jacobs (ed). Paris (2001), 141-155.
- 25 - Complexity of environment and parsimony of
decision rules in Insect societies
Detrain C.
and J.L. Deneubourg
The Biological Bulletin, 202 (2002), 268-274.
- 26 -
Dynamics of
aggregation and emergence of cooperation
Deneubourg
J.L., Lioni A. and Detrain C.
The
Biological Bulletin,
202 (2002), 262-267.
Ants
and other social insects
- Insectes Sociaux - official journal of the
International Union for the Study of Social Insects (IUSSI)
- IUSSI -
official web site
- The Social Insects Web
- UIEIS - section française de l'IUSSI
Collective
intelligence and robotics
·
Silsoe Research Institute : Robots used in agriculture and stock farming
·
Ecole
Polytechnique de Lausanne -
Micro-robots societies
Ongoing
projects