Effects of ant predation and mushroom desiccation on the survival of mycophagous Drosophila tripunctata larvae
1992
Lewis, G.P. | Worthen, W.B.
This field experiment examined the relative effects of natural levels of predation by ants and desiccation of host fungi on the survival of mycophagous Drosophila tripunctata larvae. Twenty Drosophila tripunctata larvae were added to each of forty Agaricus bisporus mushrooms placed in plastic cups in a forest in northwestern South Carolina, USA. The cups either admitted or excluded ants and were covered with either solid or mesh lids to alter mushroom desiccation rate. After four days in the forest, the cups were brought to the laboratory and flies emerging from the mushrooms were collected, dried, and weighed. The effects of predation and desiccation on the percentage of flies surviving and their mean mass were analyzed with factorial ANCOVA tests. Ant predation reduced survivorship from 42.5% to 26.5 %. Lid type marginally affected mushroom desiccation but did not affect fly survival or fly mass. Ant predation was a more important source of larval mortality than the small desiccation effects elicited by the lid treatments.
显示更多 [+] 显示较少 [-]