Population structure of seabass in Portugal: evidence from allozymes

Starch-gel electrophoresis was used to assess the level and distribution of genetic variation in juvenile European seabass sampled from five different nursery grounds along the coast of Portugal between November 1992 and February 1994. Thirty-eight loci were examined, of which six ( AAT-3*, ADA*, GPI-1*, GPI-2*, G3PDH-2*, SOD* ) were polymorphic at the 99% level and were used in population surveys. Low but statistically significant multilocus F _ST values suggest that population structuring exists along the Portuguese coast. There is some restriction in gene flow between the population at Faro and all other sites to the north.     

Trace metal requirements in total parenteral nutrition (TPN). 5. Formation constants for the copper(II)--histidine ternary complexes with threonine, lysine, glycine, phenylalanine, valine, and cystine, and discussion of their implications regarding the copper distribution in blood plasma during TPN and the evaluation of the daily dose of copper

Specific metal deficiencies have been reported to affect patients receiving total parenteral nutrition (TPN). Our previous studies on the topic were devoted to the computer-based interpretation of the extra urinary excretion of zinc; a theoretical approach was also proposed, with a view to compensating for the extra losses of this metal. Similarly, the present work deals with the problem of TPN-induced copper deficiency and its remedy. As is the case for zinc, the TPN-induced excretion of copper clearly stems from the relative mobilization of the plasma protein-bound pool of this metal into its diffusable low-molecular-weight fraction; this phenomenon being due to the competitive complexation of copper by the amino acids of the nutritive solution. The computer simulation of this effect thus required that first the equilibrium constants be experimentally determined for the main complexes of copper that might form in the solution as well as in plasma during the infusion. Accordingly, complex formation in the copper-histidine ternary systems with threonine, lysine, glycine, phenylalanine, valine, and cystine was investigated by potentiometry at 37 degrees C in NaCIO4 0.15 mol X dm-3. The implications of the results obtained are discussed with regard to the interpretation of the copper excretion and the estimation of the desirable daily dose of this metal for the TPN mixture under consideration.     

The Vallonnet cave on the northern Mediterranean border: A record of one of the oldest human presences in Europe

Prehistoric sites testifying to human presence older than one million years in Europe are rare, and in the current state of knowledge, the oldest of them have been dated to around 1.4–1.5 Ma. The Vallonnet cave at Roquebrune-Cap-Martin in the Alpes-Maritimes, on the Mediterranean border, is one of the oldest sites in France to have yielded evidence of human activity: a lithic assemblage of about a hundred pieces and traces of butchery on bones of an Epivillafranchian fauna. The archaeological levels of this small cave were recently dated between 1.1 and 1.2 Ma by U-Pb correlated with paleomagnetic data. The site was occupied alternately by large carnivores that used it as a den or a lair, and by hominins that stayed there briefly in bivouac. The lithic remains are mainly percussion tools, shaped pebbles, flakes and cores, whose raw materials are local, or even semi-local, and on the whole not very diversified with mainly limestone, and to a lesser extent sandstone, quartzite, flint and quartz. This assemblage is attributed to a Mode 1 technology (Oldowayen), among which macro-tools (hammerstones, shaped and fractured pebbles) are found alongside rarer elements resulting from debitage operating chains aimed at producing sharp-edged flakes, very rarely retouched. The bipolar-on-anvil flaking technique could be identified from the characteristics of some artifacts. Several refitting flakes on shaped pebbles or percussion tools attest to knapping and percussion activities in the cave. Hominins consumed the remains of large herbivore carcasses, as attested by the presence of cutting and fracturing marks on some bones. The presence of a freshwater source in the immediate vicinity, and the knapping and butchering activities here therefore document the subsistence behavior of Lower Pleistocene human groups, certainly in competition with the carnivores present.     

Reproductive biology of cuckoo ray Leucoraja naevus

The present study is the first to provide data on the reproductive biology of cuckoo ray Leucoraja naevus in Portuguese continental waters. No difference in size at maturity was detected between sexes, which was estimated as 56 cm total length. Spawning occurs all year round, but maximum activity was during winter months. Maximum fecundity is c. 63 eggs female(-1) year(-1) . Encapsulated eggs are released in batches, nine in total with a mean number of seven extruded eggs in each batch.     

Étude analytique d’une clavicule complète de subadulte d’Homo antecessor (site de Gran Dolina, Sierra d’Atapuerca, Burgos, Espagne)

This study reports on the skeletal remains of an infant clavicle - specimen ATD6-37 - belonging to the Homo antecessor species, unearthed at Lower Pleistocene level TD6 of the Gran Dolina site (Sierra de Atapuerca). Studied alongside a further adult specimen - ATD6-50 -, they provide us with significant information on two key paleobiological aspects of these early humans: body shape and development. Based on the analytical results, the paper proposes a more accurate proportional method for determining age at death is applied to the fossilized infant clavicle under study. It goes on to hypothesize on postcranial growth and body shape and discusses morphological patterns and age at death of these early humans through comparisons with a wide range of infant dental samples and clavicular specimens in early and modern humans.     

Le bassin de l’homme du Pléistocène supérieur de Liujiang, Sud de la Chine : taille du corps, forme du corps et encéphalisation

The Late Pleistocene hominin fossil assemblage from Liujiang, South China include a fairly well-preserved cranium, a right os coxa, a complete sacrum, and other postcranial elements all belonging to a single individual. This rare discovery offers us a unique and singular opportunity in understanding this Late Pleistocene hominin's body proportion and relative cranial capacity (encephalization quotient [EQ]), and also pelvic morphology. Using the available right innominate and its mirror-imaged left side, we reconstruct Liujiang hominin's pelvis. Our analysis of the pelvis indicates that the Liujiang hominin has a very gracile and modern-like pelvic morphology. Indeed, all of the pelvic dimensions are smaller than those of other Pleistocene hominins. Moreover, the pelvic characteristics typical of Middle and Late Pleistocene hominins including Neanderthals cannot be identified in the Liujiang pelvis. In contrast, both Liujiang's metric and non-metric features indicate affinities to more recent human populations including our modern Chinese collections from Guangxi of south China. Further support of this assessment comes from the EQ value of 5.754 for Liujiang which is closer to Minatogawa 2 and modern Chinese populations than to Middle and Late Pleistocene fossil hominins. Our analysis of body shape shows that Liujiang has body proportion (i.e. body height relative to body breadth) typical of warm-adapted populations. Based on these findings, we reason that the modern physical characteristics of Liujiang may allude to a more recent geological age. Alternatively, its morphological “modernity” could also point to a much higher degree of skeletal variation within Late Pleistocene hominins in East Asia.     

Cooperation strategies, signals and symbiosis

The authors of models concerning cooperation found an interesting application point in mutualism and symbiosis. Phenomena which are to be found in symbiosis are integrated by the various models in relation to the 'Prisoner's Dilemma': 'cost-benefit' ratio components, signals, neighbourhood interaction or reciprocity. Reciprocal altruism is found in symbiosis, but others strategies seem more to reflect human societies, where choice is unrestricted. It is very difficult to give a value to cost and benefit equilibriums. The biological environment interferes and a model based on a dominant strategy is often limited or insufficient to report on the living system's evolution.     

Karyological and taxonomic notes on Cytisus Desf. Sect. Spartopsis Dumort. and Sect. Alburnoides DC. (Genisteae, Leguminosae) from the Iberian Peninsula and Morocco

Karyological information on Cytisus species indicates at least two chromosome numbers for most of the taxa. This instability is, a striking karyological feature of Cytisus . Chromosome numbers of taxa in Sect. Spartopsis and Sect. Alburnoides, both well represented in Morocco and the Iberian Peninsula, are presented here. We provide the first data on chromosome numbers for the Moroccan taxa: C. grandiflorus subsp. barbarus , and subsp. haplophyllus (n = 23, 2 n = 46) , C. maurus (2 n = 48), C. megalanthus ( n = 23), C. arboreus subsp. arboreus , subsp. baeticus , and subsp. catalaunicus (2 n = 50), C. valdesii ( n = 23 ). New populations from the Iberian Peninsula have been counted: C. grandiflorus subsp. grandiflorus (2 n = 46), C. scoparius subsp. scoparius ( n = 23) , C. striatus subsp. eriocarpus ( n = 23, 2 n = 46), C. multiflorus (n = 23), C. oromediterraneus ( n = 23, 24). Our data confirm the instability of the chromosome number in Cytisus . The presence of B chromosomes in C. valdesii and C. megalanthus , as well in other species, is discussed in relation to this instability and previous data. We suggest that instability of the chromosome number within a taxon, and even in the same population, may be related to the breakage of A chromosomes and the appearance of B chromosomes.     

Karyological and taxonomic notes on Genista L. (Papilionoideae, Leguminosae) from the Iberian Peninsula

Karyological information about Iberian Genista species is limited because of their wide geographical distribution. It is a major factor in the understanding of a genus whose genetic evolution is mostly related to aneuploidy and euploidy. The chromosome numbers of the following taxa have been counted: G. carpetana subsp. carpetana (n = 20), G. cinerascens (n = 12), G. micrantha (n = 18), G. mugronensis subsp. rigidissima (n = 18), G. ramosissima (2n = 48) and G. tinctoria (n = 24). The previously-assumed uniformity of chromosome number (n = 24) for all the subspecies of G. cinerea is supported here by data from subspp. murcica and speciosa. In G. florida, a new chromosome number, n = 23, has been found for both subspecies (florida and polygaliphylla). A discussion of the discrepancies between these data and previous ones is included. A new level of ploidy has been found in G. tuurnefortii subsp. tournefortii (n = 32). The data stress the necessity of obtaining chromosomal information from a number of plants of a taxon before its characteristic number is clear, and indicate that more chromosomal data will help the understanding of the cytological diversity within taxa in Genista.