T}tE taxonomic relationship of the Blue Goose (Chen caerulesceus cacrulescens) and the Lesser Snow' Goose (Chcn hyperborca hyperborea) has long created controversy among avian systematists, e.g., Blaauw (1908), Soper (1930), Sutton (1932), Manning (1942), and Manning et aI. (1956). I believe that the two forms are conspecific and that the species consists of two subspecies: a large form, Chcn c...

SYNOPSIS. Some of the accumulated knowledge on the complex problems involved in the transmission of helminths of domestic animals in the USA is summarized. The lollowing conditions are usually necessary for the development outside the final hosts of infective stages of these helminths: moderate temperatures, adequate moisture, oxygen, and protection from freezing, desiccation and direct sunligh...

a better understanding of the factors influencing the germination of weed seeds could facilitate the development of more effective cultural weed management practices. the aim of this research was to determine the effects of environmental factors on seed germination of cutleaf groundcherry (physalis angulata l.). results showed that application of gibberellic acid (ga3) was effective treatment f...

In this paper, we prompt public policy performance evaluation method based on local fractional algorithm. This paper takes the public value as a basic framework to build a system and it combines the execution process of ecological construction policies with the performance evaluation of the ecological effects. Then it extracts index factors from some aspects such as the "fairness" of the policy...

Article history: Received 31 December 2004 Received in revised form 3 December 2005 Accepted 14 December 2005 Ecological data are difficult to analyze due to complexity residing in the ecological systems with the variables varying in non-linear fashion. Efficient methods are required to properly extract information out of the complex data. Wavelets have good time–frequency (timescale) localizat...

This paper studies aquatic ecological±economic systems such as the Chesapeake Bay. The stability of such eco-logical±economic systems depends on the successful functioning of a small number of generalist species in a wide range of ecological and economic conditions. We ®rst characterize the persistence of such systems. We then analyze the dynamic and the stochastic aspects of the resource alloc...

Ecological constraints on independent breeding are recognised as major drivers of cooperative breeding across diverse lineages. How the prevalence and degree of cooperative breeding relates to ecological variation remains unresolved. Using a large data set of cooperative nesting in Polistes wasps we demonstrate that different aspects of cooperative breeding are likely to be driven by different ...

About 40 years ago, scientists first strongly advocated the integration of population ecology and population genetics into population biology (Singh and Uyenoyama, 2004). Even today these two disciplines are not really integrated, but there is a general appreciation of population genetic con­ cepts in population ecology and vice versa. For example, the new subdiscipline molecular ecology, and m...