Interactions between species contribute to macro-and microevolution as well as to
community structure and functioning. In addition to direct predator–prey relations, many
other interactions (competition, facilitation, inhibition, etc.) may be key to the structure and
functioning of communities. Such interactions often occur between species belonging to the
same trophic level, and have already been demonstrated between species of bacterial-
feeding nematodes, but the exact mechanisms remain poorly understood. Hence, it is …

Interactions between species contribute to micro-evolution as well as to community structure
and functioning. In addition to direct predator-prey relations, many other interactions
(competition, facilitation, inhibition,...) may be key to the structure and functioning of
communities. Such interactions often occur between species belonging to a same trophic
level, and have already been demonstrated between species of bacterial-feeding
nematodes, but the exact mechanisms remain poorly understood. Hence, it is difficult to …