The change in avian clutch size with latitude is a celebrated example of geographic variation in a vertebrate life-history trait. Alternative hypotheses for this pattern invoke nest predation, limited food for nestlings, or post-fledging juvenile mortality as selection pressures leading to small clutch size of tropical birds. We manipulated the clutch size of Spotted Antbirds (Hylophylax naevio...

Parent-offspring conflict over clutch size may lead to siblicidal behavior between juveniles. In parasitoid wasps, selection for siblicide in small broods is predicted to produce a dearth of gregarious broods with few eggs. Here we document the clutch size distribution in the Bethylidae, a large family of aculeate parasitoids. Small gregarious clutches are the most common. Further data suggest ...

The occurrence of Microcystis blooms is a worldwide concern that has caused numerous adverse effects on water quality and lake ecology. Elevated ammonia and microcystin concentrations co-occur during the degradation of Microcystis blooms and are toxic to aquatic organisms; we studied the relative and combined effects of these on the life history of the model organism Daphnia magna. Ammonia and ...

Endoscopic submucosal dissection (ESD) is a minimally invasive method of treating early-stage tumors of the digestive tract. However, duodenal ESD is technically difficult, with high complication rates resulting from poor control of the endoscope, the thin duodenal wall, and the potential for exposure to pancreatic juices [1–2]. This study evaluated the safety of ESD using the short-type Clutch...

Parasites can have dramatic effects on life-history decisions of hosts such as timing of reproduction, clutch size, and investment in individual offspring, depending on the timing of parasite effects on host fitness. Moreover, parasites may influence the optimum values of important life-history traits such as clutch size and brood size by having different fitness effects for large and for small...

Female Nasonia vitripennis lay fewer eggs and increase the proportion of male offspring when ovipositing in previously parasitized hosts compared to unparasitized hosts. This study examines the location and nature of the cues that females use in these clutch size and sex ratio decisions. Neither the sex ratio nor the clutch size response relies on chemical cues on, or a hole drilled in, the out...

GEOGRAPHIC variation in clutch size and its possible adaptive significance have been examined by many authors, most notably Moreau (1944), Lack (1947, 1948, 1954, 1966, 1968), Skutch (1949, 1950, 1967), WynneEdwards (1962), and Klomp (1970). Although these authors examined a broad spectrum of orders, the majority of data are for passerines. This paper reports an examination of clutch size in ow...

Biological impacts of climate change are exemplified by shifts in phenology. As the timing of breeding advances, the within-season relationships between timing of breeding and reproductive traits may change and cause long-term changes in the population mean value of reproductive traits. We investigated long-term changes in the timing of breeding and within-season patterns of clutch size, egg vo...

In this paper the modelling of a double clutch transmission with an appropriate controller is presented. An accordant library for modelling different levels of detail and the use of defined state signals are introduced. Furthermore, the control of the transmission with the simulation of shifting cycles is discussed. By varying the driver models it is possible to drive miscellaneous drive and sh...

We investigated one causal explanation for geographic variation in clutch size and aggregative feeding of the pipevine swallowtail, Battus philenor. Populations in California lay larger clutches than those in Texas, and larger feeding aggregations grow at an accelerated rate on the California host plant. Using reciprocal transplant experiments with larvae from California and Texas populations, ...