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The Southern Giant Petrel (Macronectes giganteus (Gmelin, 1789); Aves, Procellariiformes), ranging from New Zealand to the Graham Peninsula and Patagonia and also from coastal Antarctica to Gough Island, displays significant geographic variation throughout its range. Six breeding provinces were identified, which show significant interpopulational variation. The formerly proposed subspecies Macronectes giganteus giganteus and Macronectes giganteus solanderi were confirmed. Macronectes giganteus solanderi has smaller homologuous parts than M. o Le Petrel geant meridional (Macronectes giganteus (Gmelin, 1789); Aves, Procellariiformes), dont la repartition s'etend de la Nouvelle-Zelande a la peninsule de Graham et la Patagonie, ainsi que de la cote de l'Antarctique a l'ile Gough, presente une variation geographique significative a travers toute son aire de repartition, compose de six provinces--des regions qui presentent une variation interpopulationnelle significative. Les deux sous-especes proposes anterieurement, Macronectes giganteus giganteus et Macronectes giganteus solanderi, sont confirm s doi: 10.1139/Z09-134, Introduction The Giant Petrel was once considered a single polymorphic species, Macronectes giganteus (Gmelin, 1789). Since the mid-1960s (Warham 1962; Bourne and Warham 1966; Voisin 1968), this taxon has been [...]

In Gabon, two major species of Loranthaceae, Phragmanthera capitata (Sprengel) Balle and Globimetula braunii (Engl.) Danser to a lesser extent, parasitize Hevea brasiliensis (Mull.) Arg. The behavior of different clones of rubber trees facing the Loranthaceae parasitism has been studied in the large industrial plantation of Mitzic and in three neighboring smallholding plantations. The clones PR 261, RRIM 600 and PB 260, although never totally resistant, are far less susceptible to Loranthaceae than the clones AVROS 2037, PB 217, PB 235 and GT 1. The parasite development kinetics was more rapid on the most susceptible clones. Phellem thickness, cortical parenchyma thickness and tannin cell density were independent of susceptibility. The number of tree ramifications was significantly different between the clones. Interestingly, on the least susceptible trees, being also the most ramified, the parasite showed the slowest development. [ABSTRACT FROM AUTHOR]

Biodiversity can be regarded as the result of the dynamic processes starting with speciation and ending with species extinction. Speciation urges populations of organisms within an already-existing species to change as a consequence of ecological change. It can occur everywhere as the selective pressures causing it are randomly distributed ( , p. 4); hence, a need to promote a development policy that does not endanger these natural processes. This conservation concept addresses a global ecological policy and is different from the more classical concept of conservation based on the promotion of natural parks to preserve rare species and their direct habitats. The latter concept has the disadvantage to lead to the protection of limited surfaces, which cannot harbour most of speciation centres and leaves the rest of the world unprotected. Examples will illustrate the dangers faced by continental and insular speciation centres. [ABSTRACT FROM AUTHOR]

We carried out a Principal Component Analysis on 196 Iberian and Common Chiffchaffs of both sexes (live and collection specimens), characterized by seven variables derived form wing, tarsus and bill measures. This method, complemented by colour comparison of the taxa, led us to the following conclusions. (1) Phyllopneuste brehmii, Homeyer, 1871 is a junior synonym of Sylvia collybita, Vieillot, 1817. The correct name for the Iberian Chiffchaff is Phylloscopus ibericus (Ticehurst 1937). (2) P. ibericus is itself represented by two subspecies: the southern form P.i ibericus (Ticehurst 1937), and the northern form, for which we propose the name P.i. biscayensis ssp. nov. (3) The Common and Iberian Chiffchaffs are very distinct in the contact zone. But an overall geographical variation following Bergmann's and Allen's rules within both taxa generate an ecomorphological convergence, i.e. P.i. ibericus and the populations of P.c. collybita from northern central Europe have similar sizes. This may explain why previous authors were unable to diagnose the two taxa on morphological criteria alone. [ABSTRACT FROM AUTHOR]

Abstract In the western Pyrenees (Southwest France and Northwest Spain), a narrow hybrid zone exists between the common chiffchaff Phylloscopus (collybita) collybita and the Iberian chiffchaff Phylloscopus (c.) brehmii . In this zone, which is approximately 20 km wide, mixed matings and individuals singing the songs of both taxa occur at substantial frequencies (24 and 8.6%, respectively), suggesting frequent hybridization. Previous studies have shown very weak mitochondrial gene flow (Nm = 0.065), whereas four microsatellites suggested much higher nuclear gene flow (Nm = 4.9). In this study we used the amplified fragment length polymorphism (AFLP) method in order to identify hybrids and early backcrosses. We typed 91 birds from both allopatric and sympatric areas for 12 informative AFLP markers (of > 141 polymorphic fragments), obtained by screening 13 AFLP primer combinations. These individuals were previously typed for song (brehmii, collybita or mixed singers), mitochondrial DNA (mtDNA) haplotype and allelic genotypes at four microsatellite loci. Assignment tests demonstrated that in the zone of sympatry, a substantial number of intermediate genotypes existed among the birds previously believed to be pure collybita and brehmii , based on song and mtDNA haplotype. The majority of the mixed singers had intermediate genotypes. Our data suggest that the fraction of the adult population having a hybrid origin (hybrids or backcrosses) is in the order of 10%. With such a frequency of genetic hybrids, there would have been much more mtDNA introgression than observed, had female hybrids been perfectly fertile/viable. This result is consistent with male-biased gene flow and Haldane’s rule. [ABSTRACT FROM AUTHOR]

Aim Different continental and insular speciation processes are reviewed. The areal and clinal conceptions of speciation studies are discussed. I propose a revisited cline theory reconciling cline mechanics and allopatric speciation as cline analysis allows quantification in speciation description more easily and integrates polymorphism within speciation processes. In addition, insular speciation illustrates what could have been the first allopatric stages of many current continental speciations. Intrinsic correspondence is shown between areal and clinal conceptions, and between continental and insular speciation processes; this article is thus an essay towards a unified theory of speciation biogeography. [ABSTRACT FROM AUTHOR]

This paper is on production planning and inventory control in systems where manufacturing and remanufacturing operations occur simultaneously. Typical for these hybrid systems is, that both the output of the manufacturing process and the output of the remanufacturing process can be used to fulfill customer demands. Here; we consider a relatively simple hybrid system, related to a single component durable product. For this system, we present a methodology to analyse a PUSH control strategy (in which all returned products are remanufactured as early as possible) and a PULL control strategy (in which all returned products are remanufactured as late as is convenient). The main contributions of this paper are (i) to compare traditional systems without remanufacturing to PUSH and to PULL controlled systems with remanufacturing, and (ii) to derive managerial insights into the inventory related effects of remanufacturing. [ABSTRACT FROM AUTHOR]

Multilevel lotsizing is one of the most challenging subjects in production planning, especially in the presence of capacity constraints. In this paper we investigate lotsizing heuristics for assembly production systems with a bottleneck. More specifically, we discuss heuristics based on Linear Programming (LP), and compare the performance of these heuristics with the performance of approaches based on simulated annealing and tabu search techniques. A comparison of the three heuristics on a set of test problems shows that simulated annealing and tabu search perform well compared to pure LP-based heuristics, but the effectiveness of the latter heuristics can be improved by combining them with elements from simulated annealing and tabu search. [ABSTRACT FROM AUTHOR]