breeding places of a. stephensi were studied in bandar abbas city, on persian gulf to determine the characteristics of breeding places and the larval density. the conventional standard dipper was used and all stages in ten dippers were considered as measuring scales. the study showed the presence of larvae in seven different types of breeding places which were: barrels and pounds which were use...

Spawning of Northeast Arctic (NA) cod stretches from late February to early May over 1500km along the Norwegian coast. Hatching occurs from late March to late May, a period when the number of daylight hours increases from 11 to 17. Larval feeding opportunities are constrained by prey abundance and environmental variables such as light, while temperature determines the maximum growth potential. ...

1. Host plant density can affect insect herbivore oviposition behaviour, which can, in turn, affect both plant and herbivore populations. Because clear generalisations about density effects on oviposition remain elusive, a better understanding of underlying mechanisms is needed. One such mechanism is plantmediated effects (i.e. changes in plant traits with density), which are often suggested bu...

A central goal of population ecology is to identify the factors that regulate population growth. Monarch butterflies (Danaus plexippus) in eastern North America re-colonize the breeding range over several generations that result in population densities that vary across space and time during the breeding season. We used laboratory experiments to measure the strength of density-dependent intraspe...

During population outbreaks, top-down and bottom-up factors are unable to control defoliator numbers. To our knowledge, details of biotic interactions leading to increased population density have not been studied during real population outbreaks. We experimentally assessed the strength of plant defenses and of insect immunocompetence, assumed to contribute to active insect resistance against pa...

Sponge larval flagellated cells have been known to form the external layer of larva, but their subsequent fate and morphogenetic role are still unclear. It is actually impossible to follow flagellated cell developmental fate unless a specific marker is found. We used percoll density gradient fractionation to separate different larval cell types of Halisarca dujardini (Demospongiae, Halisarcida)...

BACKGROUND Aedes aegypti (L.) is the primary vector of dengue, the most important arboviral infection globally. Until an effective vaccine is licensed and rigorously administered, Ae. aegypti control remains the principal tool in preventing and curtailing dengue transmission. Accurate predictions of vector populations are required to assess control methods and develop effective population reduc...

The effects of larval crowding on survival, weight at metamorphosis and development time were assessed in the dengue mosquito, Aedes aegypti L., under a controlled environment. Larval cohorts were bred at 7 different densities (4, 8, 16, 32, 64, 128 and 256 larvae / 175 ml pot), while keeping constant water volume and food amount and quality, under controlled temperature and photoperiod. Natura...

BACKGROUND The average nitrogen-to-phosphorus ratio (NratioP) of insect herbivores is less than that of leaves, suggesting that P may mediate plant-insect interactions more often than appreciated. We investigated whether succession-related heterogeneity in N and P stoichiometry influences herbivore performance on N-fixing lupin (Lupinus lepidus) colonizing primary successional volcanic surfaces...