Migratory connectivity by birds may mutually affect different ecosystems over large distances. Populations of geese overwintering in southern areas while breeding in high-latitude ecosystems have increased strongly over the past decades. The increase is likely due to positive feedbacks caused by climate change at both wintering, stopover sites and breeding grounds, land-use practices at the ove...

The newly invasive soybean aphid,Aphis glycinesMatsumura, has seriously threatened soybean production in North America, after having spread to 20 states in the United States and several southernprovincesofCanada.Control ofA. glycineshas focusedonapplicationsof insecticides, which are not a long-term solution to soybean aphid pest management. In autumn, soybean aphids start producing alate femal...

Cretaceous polar dinosaur faunas were taxonomically diverse, which suggests varied strategies for coping with the climatic stress of high latitudes. Some polar dinosaurs, particularly larger taxa such as the duckbill Edmontosaurus Lambe, 1917, were biomechanically and energetically capable of migrating over long distances, up to 2600 km. However, current evidence strongly suggests many polar di...

A 20-year capture-recapture study of alpine grasshoppers spanned three distinct sequences of abundance, featuring in turn dis-equilibrium, equilibrium and secondary cyclic equilibrium. This succession of population patterns in the most abundant species, Paprides nitidus, retained high stability between generations. It arose via superimposed life-cycle pathways and adaptive responses between gra...

Salmon lice Lepeophtheirus salmonis infestation of sea trout Salmo trutta results in both additional marine mortality and behavioral changes which may contribute to population decline. For effective management activities that increase exposure salmon lice, such as aquaculture, it is necessary have a full understanding how affect populations. An individual-based model (IBTRUTTA) was therefore de...

The monarch butterfly annually migrates from central Mexico to southern Canada. During recent decades, its population has been reduced due to human interaction with their habitat. We examine the effect of herbicide usage on the monarch butterfly’s population by creating a system of linear and non-linear ordinary differential equations that describe the interaction between the monarch’s populati...

The study of sexual selection has traditionally focused on events and behaviours immediately surrounding copulation. In this study, we examine whether carry-over effects from the non-breeding season can influence the process of sexual selection in a long-distance migratory bird, the American redstart (Setophaga ruticilla). Previous work on American redstarts demonstrated that overwintering in a...

UNLABELLED Polyamines are found in all groups of cyanobacteria, but their role in environmental adaptation has been barely investigated. In Synechocystis sp. strain PCC 6803, inactivation of spermidine synthesis genes significantly reduced the survivability under chill (5°C)-light stress, and the survivability could be restored by addition of spermidine. To analyze the effects of spermidine on ...

Renal adenocarcinomas of the leopard frog, Rana pipiens, collected in Kandiyohi County, Minn., were fixed for electron microscopy prior to and 4, 7, 13, and 16 days after the entry of host frogs into lakes for overwintering. Fifteen tumors were studied. No herpesviruses were detected in 4 tumors of prehibernating frogs. Two tumors of frogs autopsied on Day 4 of overwintering did not show viruse...

Estimates of carbon flux to the deep oceans are essential for our understanding of global carbon budgets. Sinking of detrital material ("biological pump") is usually thought to be the main biological component of this flux. Here, we identify an additional biological mechanism, the seasonal "lipid pump," which is highly efficient at sequestering carbon into the deep ocean. It involves the vertic...