Effects of age,territoriality and breeding on survival of Bonelli’s Eagle Aquila fasciata

Survival typically contributes most to population trends in long‐lived birds and its accurate estimation is therefore vital for population management and conservation. We evaluated the effects of age, territoriality and reproduction on survival in Bonelli’s Eagle Aquila fasciata through multistate capture‐mark‐recapture analyses on a long‐term dataset. Monitoring was carried out in southeast France (1990–2008) and involved the surveying of territorial Eagles, the marking of fledged chicks, and the recording of resightings and recoveries of marked non‐territorial and territorial birds. Survival improved with age, but territoriality was not retained in the best model; yearly survival was estimated at 0.479 for fledglings (to 1 year of age), 0.570 for 1‐ and 2‐year‐olds, and 0.870 for 3‐year‐old and older individuals. The second best model supported a further increase in survival from 3‐year‐olds (0.821) to older individuals (0.880). In the third best supported model, territoriality enhanced survival, but only in 2‐year‐olds (0.632 vs. 0.562 for non‐territorial). We found no correlation between the previous breeding stage and future survival, consistent with the long lifespan of the study species. Nevertheless, 4‐year‐old and older successful breeders were more likely to breed the following year than failed adult breeders (0.869 vs. 0.582), suggesting that the cost of reproduction is small in comparison with the variation in quality among individuals or their territories.     

A new Late Jurassic turtle from Spain: phylogenetic implications,taphonomy and palaeoecology

Abstract: The Jurassic was an important period in the evolution of Testudinata and encompasses the origin of many clades, and this is especially true of Jurassic turtles from Western Europe. A new genus and species of Late Jurassic turtle, Hispaniachelys prebetica gen. et sp. nov. from the upper Oxfordian of the Prebetic (Southern Spain), is described on the basis of postcranial material. The specimen is the only known tetrapod from the Mesozoic of the Prebetic and the oldest turtle from southern Europe. A mosaic of characters indicates this is a new genus: it displays basal features including dorsal epiplastral processes/reduced cleithra, no medial contact of the extragulars and a long first thoracic rib, alongside derived characters including an absence of mesoplastra and the vertebral 3/4 sulcus crossing neural 5. The phylogenetic position of the new taxon is hard to resolve, and it might be either a paracryptodire or a basal testudine, but it is distinct from Plesiochelys. A complex taphonomic history is shown by a range of overlying grazing traces and bioerosion on the carapace. The carapace was subsequently overturned and buried ventrally up, terminating grazing activity, and was then bored by sponges before final burial. Scanning electron microscopy reveals phosphatic microspheroids associated with bacterial decay in the vascular cavities of the cancellous bone, suggesting the carapace may have acted as a closed microenvironment in which decay‐derived authigenic minerals formed.     

Variation in gene transcription and protein for key enzymes of carbohydrate metabolism in poplar xylem with respect to growth phase

We compared gene expression levels for enzymes of carbohydrate metabolism in the twig xylem of two Populus species with the seasonal levels of starch and soluble sugars (sucrose, glucose, and fructose) and relative levels of the enzymes. Plants of Populus deltoides Bartr. ex Marsh and P. balsamifera L., 3–4 years old, were grown outside in Lubbock, TX, USA in 43 L pots. The xylem in the middle portion of the twigs was sampled during the dormant period (November–February), at bud break (for P. balsamifera), and during the growth flush (April–July). The gene expression for ADP-glucose pyrophosphorylase (AGPase), sucrose synthase (SuSy), and sucrose-phosphate synthase (SPS) generally coincided with the levels of the carbohydrates in whose metabolism these enzymes are involved. Gene expression for AGPase and its protein levels were high when the xylem starch content was high (growing period). However, P. balsamifera maintained high AGPase levels in dormant and growing twigs, unlike P. deltoides whose dormant twigs had low AGPase and low gene expression. Compared to growing twigs, gene expression for SuSy and SPS and their protein levels were higher in dormant twigs when soluble sugar content was higher. No down-regulation of these genes appears to occur when pools of the associated carbohydrates are high. Contrary to our expectation, the gene expression for β-amylase was highest in growing twigs when starch content was high. High β-amylase gene expression in growing twigs may be involved in maintaining a sufficient level of soluble sugars for growth through possibly controlling the extent of starch accumulation.     

More than multiple introductions: Multiple taxa contribute to the genesis of the invasive California’s wild artichoke thistle

The history of some invasive species is so complex that their origins can be difficult to determine. One example of such invasive species is the California invasive known as “wild artichoke thistle” (Cynara cardunculus var. sylvestris), found in natural and disturbed ecosystems. Wild artichoke thistle is a Mediterranean native and the progenitor of two domesticated horticultural taxa, artichoke and cardoon. Different hypotheses regarding the origins of California plants have included introductions by 19th century Italian immigrants and the de-domestication (evolutionary reversion to wild-type morphology) of feral (escaped, free-living) cultivars. Using microsatellite markers, we compared the genetic constitutions of 12 artichoke thistle populations in California with possible progenitor populations: 17 Spanish and Italian wild populations and eight different artichoke and cardoon cultivars. Each California population was compared with its putative progenitors using STRUCTURE analysis. Our results suggest that California's artichoke thistle populations are polyphyletic. Surprisingly, two-thirds of California's populations closely matched populations from the Iberian Peninsula. Three populations matched domesticated artichoke. One population appears to have wild and cultivar hybrid ancestry. Alleles specific to Italian populations were found at low frequencies in some California plants, suggesting that Italian wild plants may have been in California, but have left a trivial genetic legacy. Given that the de-domesticated plants in this study appear to be as invasive as the wild taxon, we conclude with a discussion of the role that ferality and de-domestication may have in plant invasions.     

TRAINING, VALIDATION AND MAINTENANCE OF A PANEL TO EVALUATE THE TEXTURE OF DRY BEANS (PHASEOLUS VULGARIS L.)

The inclusion of dry beans in diets has clear health benefits. However, consumers in developed countries mainly choose beans for their sensory qualities, especially for their texture. This article describes the constitution, training and validation of a panel of judges to evaluate the texture of dry beans. The judges were trained in the perception of different textures, analyzed a wide range of beans and selected seed-coat roughness, seed-coat perceptibility and creaminess/mealiness of the cotyledon as the main attributes to be scored. After training, the panel was capable of discriminating between different varieties of beans and even between beans of the same variety grown at different locations. The analysis of the behavior of the panel in a standard tasting session 2 years after its formation showed that periodic inclusion of samples from the extremes of the scales for the attributes during tasting sessions was sufficient to keep the panel trained.

PRACTICAL APPLICATIONS

This article could serve as a guide for the training of sensory panels to evaluate the texture of dry beans. It describes the selection of the attributes on which the analysis is based, references for the extreme values of the attributes and how to train the panel. It also provides a practical example of the analysis of the behavior of the panel some time after training.     

Anatomical and enzymic studies of leaves of a C3 × C4Flaveria F1 hybrid exhibiting reduced photorespiration

Flaveria pringlei exhibits C₃ CO₂ compensation concentration (Г) values averaging 53 μl CO₂/l at 21% (v/v) O₂ and 25 ± 2°C. When this species is hybridized with the C₄ species, F. brownii (male) ($\text{Г = 6 μ}\text{l CO}{}_2\text{/}\text{l}$), the F₁ hybrid plants exhibit an average Г value of 31 μl CO₂/l at 21% O₂.Although light micrographs of leaf cross-sections show that the leaves of the hybrid plants possess the mesophyll arrangement characteristic of F. pringlei leaves, the hybrid plants have some bundle-sheath chloroplasts. However, the numbers of these organelles do not appear to be intermediate with respect to the numbers in the parents and are closest to the small number present in the bundle-sheath cells of F. pringlei leaves. The activities of key C₄ enzymes (in μmol · mg Chl^?1 · h^?1) are: phosphoenolpyruvate (PEP) carboxylase, 121; pyruvate, orthophosphate (P_i) dikinase, 26; NADP-malate dehydrogenase, 2529; and NADP-malic enzyme, 82. All of these activities are substantially higher than in F. pringlei, but are only 7–10% of those in F. brownii (with the exception of the NADP-malate dehydrogenase activity). These data suggest that a C₄ cycle might be operating to a limited extent in the hybrid plants resulting in reduced photorespiration.Whether or not C₄ photosynthesis occurs in these hybrid plants, they represent the first reported C₃ × C₄ F₁ hybrids to exhibit reduced Γ-values. This cross and its reciprocal should be useful models for studying the anatomical and biochemical factors determining the development of limited C₄ photosynthesis in C₃ species.     

Overexpression of Superoxide Dismutase Protects Plants from Oxidative Stress (Induction of Ascorbate Peroxidase in Superoxide Dismutase-Overexpressing Plants)

Photosynthesis of leaf discs from transgenic tobacco plants (Nicotiana tabacum) that express a chimeric gene that encodes chloroplast-localized Cu/Zn superoxide dismutase (SOD+) was protected from oxidative stress caused by exposure to high light intensity and low temperature. Under the same conditions, leaf discs of plants that did not express the pea SOD isoform (SOD-) had substantially lower photosynthetic rates. Young plants of both genotypes were more sensitive to oxidative stress than mature plants, but SOD+ plants retained higher photosynthetic rates than SOD- plants at all developmental stages tested. Not surprisingly, SOD+ plants had approximately 3-fold higher SOD specific activity than SOD- plants. However, SOD+ plants also exhibited a 3- to 4-fold increase in ascorbate peroxidase (APX) specific activity and had a corresponding increase in levels of APX mRNA. Dehydroascorbate reductase and glutathione reductase specific activities were the same in both SOD+ and SOD- plants. These results indicate that transgenic tobacco plants that overexpress pea Cu/Zn SOD II can compensate for the increased levels of SOD with increased expression of the H2O2-scavenging enzyme APX. Therefore, the enhancement of the active oxygen-scavenging system that leads to increased oxidative stress protection in SOD+ plants could result not only from increased SOD levels but from the combined increases in SOD and APX activity.     

COMPARISON OF TWO SIMPLE METHODS FOR THE MEASUREMENT OF DETECTION THRESHOLDS FOR BASIC, UMAMI AND METALLIC TASTES

Two simple methods were followed to determine detection thresholds for the taste of substances in aqueous solution. The methods applied were: a modification of the ascending method of limits and a method based on the use of scales. Detection thresholds were calculated for the four basic tastes (sweet, salty, acid, and bitterness), umami and metallic. Reference substances for each taste were sucrose, sodium chloride, citric acid, caffeine, monosodium glutamate and iron (II) sulfate heptahydrate and the results of the two methods were compared. We found that the threshold values calculated by method ASTM-679 was within the range of concentrations identified with the scales method.     

Pituitary opioid involvement in ECS-postictal electrogenesis and behavioral depression in rats

The role of pituitary opioids in electroconvulsive shock (ECS)-induced postictal electrogenesis and behavioral depression was investigated in sham-hypophysectomized and hypophysectomized rats. These animals were divided into two subgroups and injected SC with either saline or naloxone (3 mg/kg) 10 min prior to transauricular ECS. Sham-hypophysectomized rats given saline responded to a single ECS with a 65 +/- 18% (s.e.) increase in postictal electrogenesis and a behavioral depression lasting 3840 +/- 530 sec. Naloxone significantly antagonized both the postictal increase in EEG voltage output and behavioral depression. Hypophysectomy by itself was without effect on EEG patterns and only partially attenuated the ECS-induced electrogenesis and postictal depression (31.9 +/- 9% and 2360 +/- 511 sec, respectively). However, in hypophysectomized rats, naloxone did not further antagonize these effects of ECS. Thus, it appears that pituitary opioids may, at least in part, mediate postictal electrogenesis and behavioral depression. Alternatively, since hypophysectomy only partially attenuates these phenomena, central or nonpituitary opioid peptide systems may be involved. In view of the observed decrease in responsiveness to naloxone in hypophysectomized rats, nonopioid systems cannot be ruled out as contributors to the opioid-like effects of ECS in these animals.     

Thyrotropin releasing hormone: autonomic effects upon cardiorespiratory function in endotoxic shock

These studies define potential sites and mechanisms by which thyrotropin releasing hormone (TRH) stimulates cardiorespiratory function in normotensive rats as well as in rats subjected to endotoxic shock. Changes in mean arterial pressure, pulse pressure, heart rate, and respiratory rate were determined in conscious animals following injection of TRH into the lateral, third, or fourth ventricular spaces. Injections of TRH into the third ventricular space resulted in a greater increase in cardiorespiratory variables than did fourth ventricular injection. In endotoxin-treated rats, the cardiorespiratory effects of intracerebroventricular (icv) TRH and its analog MK 771 were assessed. TRH and MK 771 were shown to act within the brain to reverse endotoxic shock hypotension; at the doses used, the pressor effects of these two tripeptides were achieved through selectively different actions upon heart rate and pulse pressure. Adrenal demedullated and sham-operated control rats subjected to endotoxic shock were injected with icv and intravenous (iv) TRH in order to evaluate the potential involvement of sympatho-medullary function in cardiorespiratory responses. The cardiovascular effects of icv TRH were dependent upon adrenal medullary integrity; effects of iv TRH were not. Doses of iv TRH which effectively reverse shock neither altered nociceptive latencies nor interfered with analgesic responses to morphine. Collectively, these studies reinforce the potential therapeutic utility of TRH and its analogs in the treatment of shock and indicate potential sites and mechanisms which mediate these salutary effects.