Unlike predators, which immediately consume their prey, parasitoid wasps incapacitate their prey to provide a food supply for their offspring. We have examined the effects of the venom of the parasitoid wasp Ampulex compressa on the metabolism of its cockroach prey. This wasp stings into the brain of the cockroach causing hypokinesia. We first established that larval development, from egg laying to pupation, lasts about 8 days. During this period, the metabolism of the stung cockroach slows down, as measured by a decrease in oxygen consumption. Similar decreases in oxygen consumption occurred after pharmacologically induced paralysis or after removing descending input from the head ganglia by severing the neck connectives. However, neither of these two groups of cockroaches survived more than six days, while 90% of stung cockroaches survived at least this long. In addition, cockroaches with severed neck connectives lost significantly more body mass, mainly due to dehydration. Hence, the sting of A. compressa not only renders the cockroach prey helplessly submissive, but also changes its metabolism to sustain more nutrients for the developing larva. This metabolic manipulation is subtler than the complete removal of descending input from the head ganglia, since it leaves some physiological processes, such as water retention, intact.
|Number of pages
|Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology
|Published - Jun 2005
Bibliographical noteFunding Information:
Acknowledgements We are grateful to A. Weisel-Eichler for valuable comments and editing of the manuscript. We would also like to thank the Kreitman fellowship and the Kreitman family for their support of Gal Haspel during his graduate studies. This work was supported by Grant 2001044 from the United States-Israel Binational Science Foundation (BSF). These experiments comply with the ‘‘Principles of Animal Care’’, publication no. 86–23 (revised 1985) of the National Institute of Health and also with the current laws of the State of Israel.
- Ampulex compressa
- Oxygen consumption
- Periplaneta americana
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Animal Science and Zoology
- Behavioral Neuroscience