We give a selective survey of oligopoly models for energy production which capture to varying degrees issues such as exhaustibility of fossil fuels, development of renewable sources, exploration and new technologies, and changing costs of production. Our main focus is on dynamic Cournot competition with exhaustible resources. We trace the resulting theory of competitive equilibria and discuss s...

Composite trace fossils are the product of two or more species of tracemakers. In many instances, such traces are also caused by different tracemaker behaviors and by tracemakers with different environmental requirements. In this study, composite trace fossils from eolianites of the Holocene Rice Bay Formation, San Salvador, Bahamas are examined. These trace fossils are likely decapod dwelling ...

The early fossil record of terrestrial arthropod herbivory consists of two pulses. The first pulse was concentrated during the latest Silurian to Early Devonian (417 to 403 Ma), and consists of the earliest evidence for consumption of sporangia and stems (and limited fungivore borings). Herbivorization of most of these tissues was rapid, representing 0 to 20 million-year (m.y.) lags from the ea...

Planktonic foraminifera are one of the most abundant and diverse protists in the oceans. Their utility as paleo proxies requires rigorous taxonomy and comparison with living and genetically related counterparts. We merge genetic and fossil evidence of "Globigerinoides", characterized by supplementary apertures on spiral side, in a new approach to trace their "total evidence phylogeny" since the...

The flyschoid sediments of the Dyakove Group (Serpukhovian–Bashkirian) are exposed in central part Donets Basin (Luhansk and Donetsk regions Ukraine Rostov Region Russia). These important for studying history geological development Dnipro-Donets Downwarp. In addition, contain deposits a number mineral resources (gold, ores silver, lead, zinc, etc.). Nevertheless, paleontological features poorly...

The study of trace fossils, the fossilized remains of animal behavior, reveals interesting parallels with recent research in behavior-based robotics. This article reports robot simulations of the meandering foraging trails left by early invertebrates that demonstrate that such trails can be generated by mechanisms similar to those used for robot wall-following. We conclude with the suggestion t...