The aim of the research was to investigate the effects of divergent selection on some production and clutch traits in Japanese quail (Coturnix coturnix japonica). Over 5 generations divergently selected two Japanese quail lines (HBW: High Body Weight and LBW: Low Body Weight) and control line (C) that derivate from a base random bred population were used in this study. Weight of first egg, age ...

Reproductive success in many avian populations declines throughout the breeding season. Two hypotheses have gained attention to explain such a decline: the ‘‘timing’’ hypothesis proposes that deteriorating food availability causes the decline in reproductive success (causal effect of breeding time), whereas the ‘‘quality’’ hypothesis proposes that individuals of lower phenotypic quality reprodu...

Negative density dependence of clutch size is a ubiquitous characteristic of avian populations and is partly due to within-individual phenotypic plasticity. Yet, very little is known about the extent to which individuals differ in their degree of phenotypic plasticity, whether such variation has a genetic basis and whether level of plasticity can thus evolve in response to selection. Using 18 y...

In migrating cells, integrin-based focal adhesions (FAs) assemble in protruding lamellipodia in association with rapid filamentous actin (F-actin) assembly and retrograde flow. How dynamic F-actin is coupled to FA is not known. We analyzed the role of vinculin in integrating F-actin and FA dynamics by vinculin gene disruption in primary fibroblasts. Vinculin slowed F-actin flow in maturing FA t...

For over a half century numerous hypotheses have surfaced aimed at explaining a key life history trait, the evolution of clutch size in birds. A principal goal has been to explain why clutch size generally increases with latitude both within species and among closely related species. Most hypotheses have stressed food limitation, predation, or seasonality. I present a novel hypothesis to explai...

Female insects have a limited energy budget to invest in reproduction. Clutch size and egg size are two traits typically involved in energy budget trade-offs, and an optimum clutch size is generally predicted. This trade-off, however, is influenced by many factors including the probability of egg parasitism. We studied this possibility in the pine processionary moth (Thaumetopoea pityocampa), w...

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...