Abstract
Adults of most species of insect parasites spend much time finding objects that influence their individual and collective well-being. The object found at any time is usually correlated with the physiological state of the parasite and with extrinsic factors existing at that time. From the standpoint of the species' economy, the most important objects to be discovered are hosts on which fertile parasite progeny can mature. Whether hosts are found and parasitized is influenced, to varying degrees with different parasite species, by whether the female has already found, or been found by, a male of the same species, and by whether she has already located food other than that provided by hosts. The present study is of factors that affect host finding by females of a pteromalid,Nasonia vitripennis(Walk.).