Long-term observation of amphibian populations inhabiting urban and forested areas in Yekaterinburg, Russia

This article presents data derived from a 36 year-long uninterrupted observational study of amphibian populations living in the city and vicinity of Yekaterinburg, Russia. This area is inhabited by six amphibian species. Based on a degree of anthropogenic transformation, the urban territory is divided into five highly mosaic zones characterized by vegetation, temperature, and a distinctive water pollution profile. Population data is presented year-by-year for the number of animals, sex ratio, and species-specific fecundity including the number and quality of spawns for the following amphibian species: Salamandrella keyserligii, Rana arvalis, R. temporaria, Lissotriton vulgaris, and Pelophylax ridibundus. These data provide an excellent opportunity to assess an urban environment from an animal population-wide perspective, as well as revealing the forces driving animal adaptation to the anthropogenic transformation of habitats

Tradeoff between robustness and elaboration in carotenoid networks produces cycles of avian color diversification

BACKGROUND: Resolution of the link between micro- and macroevolution calls for comparing both processes on the same deterministic landscape, such as genomic, metabolic or fitness networks. We apply this perspective to the evolution of carotenoid pigmentation that produces spectacular diversity in avian colors and show that basic structural properties of the underlying carotenoid metabolic network are reflected in global patterns of elaboration and diversification in color displays. Birds color themselves by consuming and metabolizing several dietary carotenoids from the environment. Such fundamental dependency on the most upstream external compounds should intrinsically constrain sustained evolutionary elongation of multi-step metabolic pathways needed for color elaboration unless the metabolic network gains robustness - the ability to synthesize the same carotenoid from an additional dietary starting point. RESULTS: We found that gains and losses of metabolic robustness were associated with evolutionary cycles of elaboration and stasis in expressed carotenoids in birds. Lack of metabolic robustness constrained lineage's metabolic explorations to the immediate biochemical vicinity of their ecologically distinct dietary carotenoids, whereas gains of robustness repeatedly resulted in sustained elongation of metabolic pathways on evolutionary time scales and corresponding color elaboration. CONCLUSIONS: The structural link between length and robustness in metabolic pathways may explain periodic convergence of phylogenetically distant and ecologically distinct species in expressed carotenoid pigmentation; account for stasis in carotenoid colors in some ecological lineages; and show how the connectivity of the underlying metabolic network provides a mechanistic link between microevolutionary elaboration and macroevolutionary diversification. REVIEWERS: This article was reviewed by Junhyong Kim, Eugene Koonin, and Fyodor Kondrashov. For complete reports, see the Reviewers' reports section.This item is part of the UA Faculty Publications collection. For more information this item or other items in the UA Campus Repository, contact the University of Arizona Libraries at [email protected]

Dissolved forms of chemical elements in near-bottom waters and interstitial waters from sediments of the Gdansk Bay, Baltic Sea

A bottom station (lander) was installed onto the bottom at station 6214 during Cruise 86 of R/V Professor Shtokman. Resulting from this installation, all the systems of the lander functioned within the predicted regimen. Potentialities of the chamber experiment technique (the lander) seem to be preferable compared to those of studies by means of the method of interstitial waters, especially for elements of variable oxidation state

Genetic Redundancy in Rye Shows in a Variety of Ways

Fifty years ago Susumu Ohno formulated the famous C-value paradox, which states that there is no correlation between the physical sizes of the genome, i.e., the amount of DNA, and the complexity of the organism, and highlighted the problem of genome redundancy. DNA that does not have a positive effect on the fitness of organisms has been characterized as “junk or selfish DNA”. The controversial concept of junk DNA remains viable. Rye is a convenient subject for yet another test of the correctness and scientific significance of this concept. The genome of cultivated rye, Secale cereale L., is considered one of the largest among species of the tribe Triticeae and thus it tops the average angiosperm genome and the genomes of its closest evolutionary neighbors, such as species of barley, Hordeum (by approximately 30–35%), and diploid wheat species, Triticum (approximately 25%). The review provides an analysis of the structural organization of various regions of rye chromosomes with a description of the molecular mechanisms contributing to their size increase during evolution and the classes of DNA sequences involved in these processes. The history of the development of the concept of eukaryotic genome redundancy is traced and the current state of this problem is discussed