On the near-surface plankton of the eastern South Pacific Ocean

A study has been made of the plankton of the near-surface water layer (0 to 30 cm) of the eastern South Pacific Ocean in the region lying to the east of the meridian 90°W, between latitudes 5°N and 35°S. This region is influenced by the Peru Current: the current brings water from high latitudes, which results in a decrease in the number of species of the local fauna of copepods of the family Pontellidae, typical of tropical near-surface plankton. Some of the widely tropical and one bicentral species are absent or rare. Least affected by the Peru Current are the waters of equatorial structure in the northern part of the region. Here, 7 species of pontellids were recorded: the widely tropical Labidocera detruncata, Pontella tenuiremis, Pontellopsis regalis, the distant-neritic Pontella danae and Labidocera acuta, the bicentral Labidocera acutifrons, and the neritic Pontellopsis lubbockii. The dominant species among these are L. detruncata and L. acuta. To the west of the convergence, in the southern part of the region, live the southern central species Pontella valida and P. whiteleggei, with Pontellopsis regalis occurring occasionally. In these regions the copepod fauna is frequently dominated by pontellids. To the south of the boundary of the waters of equatorial structure, between the coast of South America and the line of convergence, lies a region most subjected to the effect of waters from high latitudes and of upwellings. It is inhabited by 2 pontellids only: Pontellopsis regalis and Labidocera acutifrons, but they too disappear close to the coast. In this particular region the copepods Calanus australis and Centropages brachiatus are common; they are found in a thicker water layer (0 to 200 m), and are often more abundant than the pontellids.     

Availability of receptive females at the mating place and mating chances of males in the dragonfly Aeschna cyanea

Summary The females of the dragonfly Aeschna cyanea visiting ponds vary in their receptiveness to males waiting there. Individual males pay several short visits to a mating place in the course of a day, searching for receptive females. Non-receptive females prefer to oviposit at the pond in the evening, whereas receptive females arrive throughout the day. The highest number of receptive females is found on warm days during the afternoon at which time the greatest number of copulations occur. However, as the number of males and, therefore, the competition between males is also highest during these periods, the mating chances of a particular male are constant throughout the day.     

Bitte wenden Sie jetzt – Das Auto der Zukunft von Eckard Helmers WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Oktober 2009. ISBN: 978-3-527-32648-8. 204 Seiten, gebunden. €?24,90. http://www.wiley-vch-macht-neugierig.de/02_helmers/buch/bitte_wenden.php

Eckard Helmers rekapituliert die Geschichte des Automobils von den ersten Prototypen bis zum „?lschock“ 2008 und stellt ausführlich dar, um welche Schadstoffe Politiker, Lobbyisten und Umweltschützer seit Jahren streiten und welche alternativen Antriebe es bereits gibt. Detailliert wird erkl?rt, was beim Autokauf zu beachten ist, wenn man einen Beitrag zum Erhalt der Umwelt leisten m?chte. Schlie?lich entwirft Helmers eine mobile Zukunftsvision, in der Elektroantriebe eine zentrale Rolle spielen. Sein Buch ist ein engagiertes Pl?doyer für einen grundlegenden Bewusstseinswandel.