Initial attraction is followed by behaviour which is very similar to the cat mating ritual. This involves chin and cheek marking, followed by rolling on to the back and body rubbing 25 . Cats respond equally well to both enantiomers of nepetalactone, although there are two reports that racemic nepetalactone is weakly active or inactive to cats 29 . Frustratingly, the group which tested enantiomerically pure material did not test the racemate. If all of the data from the various groups is correct, this would be the first case where both enantiomers have activity and the racemate does not 30 .
Aphids are small insects which feed on the sap of plants through fine tubes.
They reproduce asexually during the summer, but sexually during the winter 31 . The females release a male attractant pheromone from their hind legs. These compounds also act as an attractant for the black bean aphid, Aphis fabae 34 . Males are only weakly attracted by this mixture, which suggests that further components are required for full activity. The lactol 12 alone is the sex pheromone of the damson-hop aphid, Phorodon humuli 36 .