The complexity of pheromone-mediated behaviour in mammals

- Pheromones are chemicals that provoke behavioural responses within a species.
- Receptors previously thought to detect pheromones instead respond to predator cues.
- Examples of redundancy and synergy are found in the pheromone code.
- Some pheromones also promote multisensory associative learning.
- The diversity of mammalian pheromones reflects behavioural complexity.

The first pheromones mechanistically characterised in insects and mammals appear to function via a relatively linear one signal, one receptor, one behaviour paradigm. Recent genetic, physiological and behavioural approaches have revealed this is just one of many ways that pheromones influence social behaviour. The mammalian pheromone receptor space is more limited than previously thought, and this is compounded by examples of multiple receptors being activated by the same pheromone. Additionally, multiple pheromones can activate the same receptor, suggesting a complex coding strategy underpins some behaviour. Pheromones can be monomolecular or multi-component, and can provoke both hardwired and learned behaviour. These new findings challenge the common perception of pheromones and their mode of action.