studies on reproductive biology are essential to assess culture potential of a fish species. mystus tengara is a popular food fish as well as preferred as an ornamental fish in west bengal. till date detailed report on reproductive biology of this fish species in the agro-climatic context of west bengal is lacking. therefore, the present work was aimed to study the detailed reproductive biology...

Merilä, J. & Pahkala, M., Department of Population Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18 d, SE-752 36 Uppsala, Sweden Laurila, A., Department of Population Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18 d, SE-752 36 Uppsala, Sweden; and Integrative Ecology Unit, Divison of Population Biology, Department of Ecology and Systematics, Unive...

In studies done a decade apart, we provide evidence of a recent shift toward a slower progression to sexual maturity as well as reduced egg production, especially among young, small female red snapper, in the Gulf of Mexico (Gulf). Slower maturation rates (among fish ≤6 years old), lower GSI values and decreased spawning frequency were observed, and were especially pronounced in the northwester...

We analyze a class of partial differential equations that arise as"backwards Kolmogorov operators"in infinite population limits of the Wright-Fisher models in population genetics and in mathematical finance. These are degenerate elliptic operators defined on manifolds with corners. The classical example is the Kimura diffusion operator, which acts on functions defined on the simplex in R^n. We ...

Population genetics has come of age. Three important components have come together: efficient techniques to examine informative segments of DNA, statistics to analyse DNA data and the availability of easy-to-use computer packages. Single-locus genetic markers and those that produce gene genealogies yield information that is truly comparable among studies. These markers answer biological questio...

Invasion by nonindigenous species has been recognized as second only to loss of habitat and landscape fragmentation as a threat to global biodiversity (Walker & Steffen 1997). The economic impact of these species is a major concern throughout the world. For example, an estimated 50,000 nonindigenous species established in the United States cause major environmental damage and economic losses th...

There is much debate about the significance of transposable elements for the organisms that host them, and the nature of the forces responsible for maintaining them in the host population. Recent theoretical and experimental studies of the population biology of transposons have shed light on these controversies.