Whereas PNS neurons in culture are intrinsically responsive to peptide trophic factors, retinal ganglion cells (RGCs) are not unless they are depolarized, or their intracellular levels of cyclic AMP (cAMP) are elevated. We show here that depolarization increases cAMP in cultured RGCs sufficiently to enhance their responsiveness and that the trophic responsiveness of developing RGCs in intact re...

Ratio-dependent and prey-dependent models of trophic interactions make very different predictions about the steady-state (equilibrial) properties of ecosystems, such as the response of equilibrium abundance and biomass of organisms in each trophic level to increased primary productivity or nutrient input. Prey-dependent heory predicts alternating positive, negative, and zero responses of trophi...

Abstract Global change is severely affecting ecosystem functioning and biodiversity globally. Remotely sensed functional attributes (EFAs) are integrative descriptors of the environmental change—being closely related to processes directly food chains via trophic cascades. Here we tested if EFAs can explain species fitness at upper levels. We took advantage a long-term time series database repro...

Understanding how trophic levels respond to changes in abiotic and biotic conditions is key for predicting how food webs will react to environmental perturbations. Different trophic levels may respond disproportionately to change, with lower levels more likely to react faster, as they typically consist of smaller-bodied species with higher reproductive rates. This response could cause a mismatc...