As global change alters multiple environmental conditions, predicting species' responses can be challenging without understanding how each environmental factor influences organismal performance. Approaches quantifying mechanistic relationships can greatly complement correlative field data, strengthening our abilities to forecast global change impacts. Substantial salinity increases are projecte...

Ecological isolation through resource partitioning is invoked as a major factor for explaining the persistence of genetically distinct yet closely related sympatric populations. Two genetically distinct sympatric populations of anadromous rainbow smelt (Osmerus mordax) exist in the middle estuary of the St. Lawrence River. The persistence of these coexisting populations in sympatry is in confli...

Abstract Climate change may cause organisms to seek thermal refuge from rising temperatures, either by shifting their ranges or seeking microrefugia within existing ranges. We evaluate the potential for stratification provide two fish species in San Francisco Estuary (Estuary): Chinook Salmon ( Oncorhynchus tshawytscha Walbaum, 1792) and Delta Smelt Hypomesus transpacificus McAllister, 1963). c...

Smelt (Osmerus mordax) were maintained at either ambient water temperature or approximately 5 degrees C and various aspects of their freeze-avoidance response were examined from early winter until early spring. Plasma levels of glycerol, trimethylamine oxide (TMAO) and urea were elevated by December 15 and continued to increase in fish held in ambient conditions. In contrast, fish held under wa...

In this study, otolith morphology and otolith contour from big-scale sand smelt, Atherina boyeri were analyzed in Lake Eğirdir and Lake İznik (natural lakes), and Hirfanlı Dam Lake (artificial lake). The otolith contour and sixteen otolith morphological characters such as width, depth, shape, sulcus acusticus shape, ostium, cauda, rostrum size-shape, and thickness, antirostrum size-shape, and t...

In this study, otolith morphology and otolith contour from big-scale sand smelt, Atherina boyeri were analyzed in Lake Eğirdir and Lake İznik (natural lakes), and Hirfanlı Dam Lake (artificial lake). The otolith contour and sixteen otolith morphological characters such as width, depth, shape, sulcus acusticus shape, ostium, cauda, rostrum size-shape, and thickness, antirostrum size-shape, and t...

An increase in intracellular Ca2+ concentration ([Ca2+]) and morphological were simultaneously observed by epifluorescence and differential interference contrast (DIC) microscopy during fertilization of the sand dollar, Clypeaster japonicus. [Ca2+], which was detected by a Ca2+ indicator, Fluo-3, initially increased just beneath the sperm-attached site on the egg surface 8.6 sec after attachmen...

We summarize information concerning Recent and Pleistocene-Holocene Uruguayan sand dollars (Mellitidae), as well as Miocene taxa (Monophorasteridae). Recent and Pleistocene-Holocene species (Encope emarginata, Mellita quinquiesperforata, and Leodia sexisperforata) are at their southernmost limits of distribution, with only E. emarginata recorded further south than Uruguay. Lower temperatures to...

Many larvae and other plankton have complex and variable morphologies of unknown functional significance. We experimentally and theoretically investigated the functional consequences of the complex morphologies of larval sand dollars, Dendraster excentricus (Eschscholtz), for hydrodynamic interactions between swimming and turbulent water motion. Vertical shearing flows (horizontal gradients of ...