Group Cherix
Forensic Entomology

Ants are key species in most ecosystems. Their number and biomass outweighs sometimes most other invertebrates. They are sometimes considered either as beneficial insects or as pests. We are working in both directions: ecology of red wood ants and ecology of tramp ants.

Ecology of red wood ants (Formica rufa group)

The alpine arc shelters many species of ants which invaded and developed since the last glaciations. Since twenty years, our research group has been concerned with the study of the distribution and biology of several species within the genus Formica. Current works are centred on the study of reproductive strategies (Formica sensu stricto and Coptoformica sub-genus). Ethological, genetic approaches are used to characterize the mating system of different species, their dispersion ability and their foundation capacities. The recent description of a new red wood ant species (Formica paralugubris Seifert, 1996) leads us to several questions dealing with distribution and reproductive strategy. The use of geographic information system (GIS) allows a more detailed approach of the local distribution of the species at the level of the alpine arc.

See also www.zoologie.vd.ch

Ecology of tramp ant species

Because of their negative impact especially on biodiversity, understanding of biology and ecology of tramp species is of prime importance to prevent or limit their distribution in fragile ecosystems. We are currently working in Galapagos archipelago to study interactions between introduced tramp ant species.

See also www.zoologie.vd.ch

After death, animal tissues are attractive to a number of insects and other invertebrates. Moreover insects, primarily blowflies (Calliphoridae) are attracted within minutes to human corpses. The maggots found may contribute to police investigation in several ways. One of them is the estimate of post-mortem interval (PMI). Since 1993 we collaborate with the Criminal Police of canton de Vaud (Inspector Claude Wyss).

As temperature is the single most important factor affecting the rate of larval development we are investigating the rate of development of different species at different temperatures.

Another important aspect is to know more about distribution and phenology of the different species involved in the process of corpses decomposition. This could help the police to discover when and where the victim died.

In order to accumulate more detailed data about these species, we conduct also field experiments with dead pigs.

See also www.entomologieforensique.ch

See: http://www2.unil.ch/ecospat/landspot/