The effects of climate fluctuations on seasonally dry forests and their fauna are important to a holistic understanding of diversification in the South American lowlands. We document the intraspecific genetic structure of the burnished-buff tanager (Tangara cayana), a species common in seasonally dry tropical forests throughout South America. Using both mitochondrial sequence and nuclear microsatellite markers, we present an intraspecific phylogeny, haplotype network, and a STRUCTURE analysis. We also develop environmental niche models and project them onto two alternate paleoclimate models of the Last Glacial Maximum and mid-Holocene. Paleoclimate projections indicate a much greater extent and connectivity of suitable T. cayana habitat during the Last Glacial Maximum (LGM), decreasing through the mid-Holocene toward the present. Both microsatellite and mtDNA sequence data are consistent with a clockwise route of colonization for the current circum-Amazonian distribution of T. cayana. The species likely originated in the Cerrado of Brazil and expanded westward through Bolivia, across the seasonally dry forests at the base of the Andes, and into Guyana and northern Brazil. Northeastern populations then expanded south into coastal Pernambuco, Brazil completing the current ring-like distribution of this species.
Addressing collisions between environmental protection and competing economic and social interests often constitutes the very core of environmental cases. At the constitutional level, a balancing approach based on the doctrine of proportionality is frequently employed to resolve contradictions between conflicting values. In this article, I demonstrate how the proportionality doctrine in its traditional meaning can be applied to balancing interests in environmental cases. Then I bring to the forefront two innovative ways of engaging proportionality in the environmental protection; one employing proportionality as an interpretative instrument with the power to help determining the scope and content of the right to environment; and the other adjusting proportionality to the form of eco-proportionality, offering a restructured framework to rule the human-nature relationship., Hana Müllerová., and Obsahuje bibliografické odkazy
Let $C(X,\mathbb Z )$, $C(X,\mathbb Q )$ and $C(X)$ denote the $\ell $-groups of integer-valued, rational-valued and real-valued continuous functions on a topological space $X$, respectively. Characterizations are given for the extensions $C(X,\mathbb Z )\leq C(X,\mathbb Q )\leq C(X)$ to be rigid, major, and dense.
We propose a new rigorous numerical technique to prove the existence of symmetric homoclinic orbits in reversible dynamical systems. The essential idea is to calculate Melnikov functions by the exponential dichotomy and the rigorous numerics. The algorithm of our method is explained in detail by dividing into four steps. An application to a two dimensional reversible system is also treated and the existence of a symmetric homoclinic orbit is rigorously verified as an example.