Secreted parasitism proteins encoded by parasitism genes expressed in esophageal gland cells mediate infection and parasitism of plants by root-knot nematodes (RKN). Parasitism gene 16D10 encodes a conserved RKN secretory peptide that stimulates root growth and functions as a ligand for a putative plant transcription factor. We used in vitro and in vivo RNA interference approaches to silence th...

Moniliformis moniliformis-infected Periplaneta australasiae and Blatta orientalis were less active than uninfected controls in behavioral arena tests under both red and white light regimes. There was a strong interaction between light regime and parasitism for substrate use by P. australasiae. Under red light, parasitism decreased the use of black horizontal surfaces, whereas under white light,...

The absence of adaptive host responses to virulent parasites and pathogens is paradoxical. We explored the theoretical possibility that the evolution of antiparasitic egg-ejection strategies was delayed by avian hosts' lifetime experiences with brood parasitism. An analytical model indicated that individual hosts' repeated exposure to parasitism decreased the relative benefits of learning-based...

Identifying the factors used by an avian brood parasite to select host nests is important in understanding the determinates of individual reproductive success, yet such factors are poorly known for most parasitic species. Insights into these factors may come from understanding the conditions under which female parasites lay more than one egg per host nest (multiple parasitism). Using genetic te...

Conspecific brood parasitism occurs in many songbird species but has not been reported in Song Sparrows (Melospiza melodia). In three separate study areas where breeding Song Sparrows experience heavy nest predation pressure and Brownheaded Cowbird (Molothrus ater) parasitism, we observed six instances in which newly laid eggs were attributable to female Song Sparrows other than the nest owners...

The parasite-host-environment system is dynamic, with several points of equilibrium. This makes it difficult to trace the thresholds between benefit and damage, and therefore, the definitions of commensalism, mutualism, and symbiosis become worthless. Therefore, the same concept of parasitism may encompass commensalism, mutualism, and symbiosis. Parasitism is essential for life. Life emerged as...

Global biodiversity decline has prompted great interest in the effects of habitat modification and diversity on the functioning and stability of ecosystem processes. However, the applicability of previous modeled or mesocosm community studies to real diverse communities in different habitats remains ambiguous. We exposed standardized nesting resources for naturally occurring communities of cavi...

Conspecific brood parasitism (CBP), defined as parasitic laying of eggs in a conspecific nest without providing parental care, occurs in insects, fishes, amphibians, and many birds. Numerous factors have been proposed to influence the evolution of CBP, including nest site limitation; effects of brood size, laying order, or parasitic status on offspring survival; randomness of parasitic egg dist...

Obligate brood parasites should synchronize parasitism with host laying to maximize egg hatchability and chick survival. While the generalist Shiny (Molothrus bonariensis), Brown-headed (M. ater), and Bronzed (M. aeneus) Cowbirds frequently synchronize parasitism with host laying, specialist Screaming Cowbirds (M. rufoaxillaris) very often fail to do so in nests of their main host, the Bay-wing...

The objective of this study was to determine the effect of egg age and pre-colonization of cysts by a saprophytic or parasitic fungus on parasitism of Heterodera glycines eggs by other parasitic fungi. In agar and in soil tests, fungi generally parasitized more eggs in early developmental stages than eggs containing a juvenile. The effect of pre-colonization of cysts by a fungus on parasitism o...