Field-testing the protandry-based mating system for the lizard, Anolis carolinesis: does the model organism have the right model?

Using the lizard Anolis carolinensis as its subject, an early and enduring model of psychobiology was presented in which neuroendocrines and social behavior interact to coordinate reproduction between the sexes. The adaptive context for the model was protandry, here defined as a "male-first" emergence pattern from winter dormancy to the onset of breeding. In the protandry scenario, males emerge, become reproductive, and contest for territories. Then, pre-reproductive females emerge to settle on male territories, whereby ovarian recrudescence is facilitated by the behavior of courting males. A collateral inference of the protandry sequence is that females are choosing their future mates from among local males and their territories (i.e., intersexual selection). The model and its assumptions, though never validated by field data, have served as the paradigm for many laboratory experiments on A. carolinensis. Recently, however, field studies described an intrasexually selected mating system for A. carolinensis, without evidence of direct female choice. Differences between the selective inferences from the two perspectives led us to test in the field a number of protandry-based characteristics previously ascribed to A. carolinensis. We monitored free-ranging adults across the winter-to-breeding period using data on sex ratios, social behavior, gut contents, sex steroids, and gonadal condition. We found no evidence of protandry, and little support for any of the associated assumptions. Instead, the sexes broadly overlapped in their temporal transition from winter retreats to an active status in the habitat, with average male reproductive development about 1-2 weeks in advance of females. We replace the traditional protandry-based A. carolinensis paradigm with a realistic onset sequence into the breeding season and a new model for the species' mating system. Our study underscores the need for field validation when laboratory-generated data are fitted to adaptive paradigms.     

Is the economic dimension inducing the other sustainability dimensions,or is it the reverse? Perceptions from the Portuguese metal industry

ABSTRACT

In organizational sustainability, the economic dimension is recognized as having a very important role. However, the discussion regarding whether it is exclusively the economic dimension that has the power to induce the other sustainability dimensions is far from agreement. The purpose of the present paper is to analyze the perceptions regarding the existence of mutual influences between the economic dimension of sustainability and the other sustainability dimensions – environmental, social and cultural – in a relevant Portuguese economic sector: the metal industry. The analysis and statistical tests performed with the 211 collected answers led to the conclusion that the influence exerted by the economic dimension on the other sustainability dimensions is perceived as dominant, both in present and future perspectives. The results also show the perception that the economic dimension is equally influenced by the environmental and social dimensions, and in a less extent, by the cultural dimension, and that all these mutual influences are perceived to increase in the future. The existence of organizational management systems has a positive effect on the perceptions regarding the existence of mutual influences between sustainability dimensions, but only for those companies with more than one certified management system. These results confirm that organizational management systems are connected to higher degrees of awareness regarding sustainability issues. Given that the great majority of the sampled industries are SMEs, the results obtained in this research demonstrate that the existence of mutual influences between sustainability dimensions is recognized even in small-sized industries.     

Is the quest for sustainable use of the planet unworldly?

SUMMARY

Is the quest for sustainable use of the planet utopian and unworldly, or an act of enlightened self-interest? Few would label the attempts to increase human longevity unworldly, yet what significance will it have in an unsustainable world? Achieving sustainability will require entire societies to emulate attributes that humans profess to admire in others. Among the dictionary definitions of unworldly are: not seeking material advantage, and spiritually minded. Since our global life-support system is vulnerable to irresponsible individual and societal practices, the consequences of unethical behaviour and lack of compassion might well be catastrophic for human society. This paper consists of a preliminary exploration of some of these issues.     

Transport of butyltins at the water‐air interface and the adsorptive behavior of tributyltin in the surface microlayer

The transfer dynamics and enrichment phenomena of monobutyltin chloride(MBT), dibutyltin chloride(DBT) and tributyltin chloride(TBT) at the water‐surface microlayer (SM) interface were studied. The transport processes of the three compounds at the interface are very fast in the estuarine environment. The mass transfer coefficients are 1.54 m/h for MBT, 2.16 m/h for DBT, 1.56 m/h for TBT. The effect of various factors, including pH, salinity, suspended particulate and temperature, on the adsorptive behavior of TBT in the water's surface microlayer was also studied.     

On the shoals of giants: natural catastrophes and the overall destruction of the Caribbean’s archaeological record

In this paper I review a host of natural and cultural processes that have affected the preservation and integrity of archaeological sites on islands in the West Indies, many of which are located in low-lying coastal areas. Given the position of the Caribbean lithospheric plate—juxtaposed between four others—it is no surprise that by its very nature the region is volcanically active and frequently associated with earthquake and tsunami events. This makes coastal zones, and related archaeological sites in the region, highly susceptible to a wide range of destructive natural events. The high frequency of tropical systems (hurricanes and storms) in the Caribbean and rising sea level, coupled with human activities such as sand mining, development, and looting, makes the region’s archaeological record one of the most vulnerable and threatened in the world. Ongoing research is dedicated to understanding how past populations may have been affected by these events in the past.     

Analysis of the ph in Europe during the period 1986–1997

The annual averages (1986–1997) of pH are analysed for the most important European Monitoring and Evaluation Programme stations in Europe. The first objective is to discover the different temporal patterns and trends for the pH. To do this, a cluster analysis is developed. The trends are analysed by linear regression for the annual averages. In general, the pH shows an increasing trend significant at 0.05 level and the annual change ranging from +0.01 to +0.05 pH‐units per year for the different clusters obtained. The second objective is to examine the spatial variability of pH in precipitation through the use of principal component analysis. Six statistically significant modes of variability are obtained for the pH which represent the 84.5% of the total variance.     

Whirligig beetle aggregations: what are the costs and the benefits?

Laboratory experiments investigated the benefits and costs of aggregation formation in the whirligig beetles, Gyrinus marinus and G. substriatus (Coleoptera: Gyrinidae). Different sized groups of whirligigs were exposed to fish predators, and capture rate per group and per individual were estimated. Attack rate per group increased with group size, suggesting that these aggregations behave as selfish herds. In another series of experiments in which whirligigs were exposed to top- and side-attacking predators, large groups were found to detect predators when they were further away than small groups. Video analysis of these groups showed that beetles tended to increase their swimming speed after exposure to a predator but did not show an increased tendency to circle. In natural aggregations, filmed in the field, swimming speed was found to be related to group size. Body condition of field collected beetles, as estimated from the regression of body mass on body length, was not found to be related to group size, implying that large groups do not suffer reduced condition. Received: 31 January 1997 / Accepted after revision: 24 November 1997     

Assessing the antipredatory defensive strategies of Caribbean non-scleractinian zoantharians (Cnidaria): is the sting the only thing?

The relative importance of chemical, nematocyst, and nutritional defenses was examined for 18 species of Caribbean sea anemones (actinarians), zoanthids, and mushroom polyps (corallimorpharians) from the Florida Keys and the Bahamas Islands, 2008–2010. Feeding assays were performed using the fish Thalassoma bifasciatum with artificial foods containing crude organic extracts of cnidarian tissues. A novel behavioral assay using brine shrimp nauplii was used to assess nematocyst defenses. The nutritional quality of cnidarian tissues was examined using bomb calorimetry and soluble protein assays. In general, actinarians invested in nematocyst defenses, zoanthids in either nematocyst or chemical defenses, and corallimorpharians lacked both, except for 1 of 3 species that was chemically defended. Relative to other coral reef invertebrates, cnidarian tissues had similar caloric values but lower soluble protein concentrations. Trade-offs between chemical and nematocyst defenses were observed for 65% of species, while habitat and behavior provided a likely explanation for undefended species.     

Utility of the QSAR modeling system for predicting the toxicity of substances on the European inventory of existing commercial chemicals∗

Many chemicals are in common commercial use for which no information on the environmental fate or toxicity exists. Recent legislation requires that many substances be assessed for their toxicity to aquatic organisms within a very short time and determine which of these chemicals need to be studied in greater detail. It would be impossible to measure the acute and chronic effects of all of these compounds on a single organism, let alone a battery of different types of organisms, communities or ecosystems. Initially, the chemicals on the European Inventory of Existing Commercial Chemical Substances (EINECS) need to be screened and relative hazard to the environment determined. In response to OECD directives, there has been a great deal of activity by government and industry scientists. At the International Workshop on Advances in Environmental Hazard and Risk Assessment it was concluded that quantitative structure activity relationships (QSAR) could and should be used in the hazard assessment process. Papers published in that volume outline the advantages, disadvantages, limitations, advances and research requirements.

The QSAR, structure‐activity based chemical modeling and information system, which was developed by the US‐Environmental Protection Agency was used to predict the acute toxicity of 113 substances from the “Old Substances”; list of the German government to the four commonly used aquatic toxicity test organisms: Daphnia magna (DM), fathead minnow (FHM), rainbow trout (RBT), and blue‐gill sunfish (BG).

Of these compounds the QSAR system predicted the acute toxicity of 87 substances towards fathead minnow. For the other three species examined the QSAR system could be used to predict toxicity for 78 compounds.

The predicted toxicities were compared to observed toxicities of compounds which have been evaluated and stored in the “Aquire”; data base. Observed toxicity values were available for at least one species for 38 compounds. The toxicities of some compounds are well predicted while those of other compounds were not well predicted. Overall, the QSAR system accurately classified the acute toxicity ranges of 50%, 64%, 56% and 56% of the compounds investigated for DM, FHM, RBT and BG, respectively. Of the compounds studied 10 were very poorly predicted, of these the QSAR system overpredicted the toxicity of three, while underpredicting the toxicity of seven. Of these seven compounds, five contained amino groups.     

How does the spatial structure of habitat loss affect the eco-epidemic dynamics?

Habitat loss is considered as one of the primary causes of species extinction, especially for a species that also suffers from an epidemic disease. Little attention has been paid to the combined effect of habitat loss and epidemic transmission on the species spatiotemporal dynamics. Here, a spatial model of the parasite–host/prey–predator eco-epidemiological system with habitat loss was studied. Habitat patches in the model, instead of undergoing a random loss, were spatially clustered by different degrees. Not only the quantity of habitat loss but also its clustering degree was shown to affect the equilibrium of the system. The infection rate and the probability of successful predation were keys to determine the spatial patterns of species. The epidemic disease is more likely to break out if only a small amount of suitable patches were lost. Counter-intuitively, infected preys are more sensitive to habitat loss than predators if the lost patches are highly clustered. This result is new to eco-epidemiology and implies a possibility of using spatial arrangement of suitable (or unsuitable) patches to control the spread of epidemics in the ecological system.     

The use of the embryo‐culture techniques in the research on the Teratogenic and Mutagenic properties of metals†

Actually, embryos can be cultured from the one‐cell stage up to the blastocyst stage, and their development can be easily monitored at any time: severe effects caused by toxic compounds are traduced by rapid embryonic death, less pronounced effects can be expressed by a lowered cleavage activity or by an arrest of the development from a particular stage. The system can be improved by transferring the embryos at the blastocyst stage in another more complete medium where they can “implant”; and form an inner cell mass with differentiated ectoderm and endoderm. Since last years, it has also become possible to culture postimplantation rodent embryos for short periods involving a number of particularly critical stages of organogenesis, such as the formation and closure of the anterior neuropore. Embryo‐culture also represents a useful system to study cytogenetic effects of chemicals which are often linked to lethal or teratogenic effects. These different possibilities are illustrated by examples of studies already performed with metals, and dealing with their teratogenic and/or cytogenetic effects on pre‐ and postimplantation rodents.     

Effects of the Ellagic acid on the N‐Acetyltransferase activity and Acetylation of 2‐aminofluorene in the rat

The effects of the ellagic acid on the in vitro and in vivo acetylation of 2‐aminofluorene were investigated in male Sprague‐Dawley rats. For in vitro examination, cytosols with or without ellagic acid co‐treatment showed different percentage of 2‐aminofluorene acetylation. For in vivo examination, pre‐treatment of male rats with ellagic acid (10 mg/kg) 24h prior to the administration of 2‐aminofluorene (50 mg/kg) resulted in a 26% and 29%, respectively, decrease in the urinary and fecal recovery of N‐acetyl‐2‐aminofluorene, and a 37% decrease in the metabolic clearance of 2‐aminofluorene to N‐acetyl‐2‐aminofluorene. This is the first demonstration that ellagic acid decrease the N‐acetylation of carcinogens in vitro and in vivo.     

Problems of the coasts erosion in the North–Eastern Black Sea Region

The seacoasts protection does not stand standard solutions. Every part of a shore needs to be creatively approached and its hydrodynamic, lithodynamic, geological, geomorphological and other peculiarities must be thoroughly studied for each particular situation. It takes a complex scientific approach considering not only local features, but also the reaction of the whole lithodynamic system in limits of which the coast protective activity is planned with consideration of calculated hydrodynamic parameters (waves, sea level, etc.).     

Evaluation of the ecological status with benthic indices in the coastal system： the case of Bohai Bay （China）

Based on biologic and environmental materials collected from coastal areas of Bohai Bay （China） in April, 2008, three biotic indices （AZTI＇s Marine Biotic Index （AMBI）, Shannon-Wiener Index and W-statistic） were applied together to evaluate the ecological status of the sampling area. The results showed a clear spatial gradient from a worse ecological status in the near-shore areas （especially around Haihe and Jiyun River Estuaries） to a better status in the offshore areas. While all the three indices could assist decision makers in visualizing spatial changes of organic pollutants in Bohai Bay, two indices, i. e., AMBI and Shannon-Wiener index, were effective in distinguishing sites from Haihe River Estuary, Jiyun River Estuary and other area. However, W-statistic can＇t tell the differences between estuaries and other area. It would be explained that organic pollutants and/or other environ- mental stresses in Bohai Bay were not strong enough to reduce the size ofmacrozoobenthos, which may cause both of the abundance and biomass curves crossed. To our knowledge, this is the first time that several benthic indices were used to assess the benthic ecological status in Bohai Bay, which gave the similar results. Furthermore, there is indication that the ecological status is related to excess input of wastewater along main rivers and outlets. In a word, AMBI, Shannon-Wiener Index and W-statistic could be able to assess the benthic ecological status of Bohai Bay under the organic pollutants pressure.     

After the flames then what? exploring the linkages between wildfires and household food security in the northern Savannah of Ghana

ABSTRACT

This study deploys the livelihoods theory in political ecology together with integrated methods including remote sensing, participatory geographic information systems, interviews and focus group discussions to explore the intricate and dynamic linkages between perennial wildfires and household food insecurity among smallholder farmers in the northern savannah zone of Ghana. Our results suggest that wildfires are a major pathway to household food insecurity in two ways, as perceived by the farmers. First, in instances where wildfires destroy the major crops of smallholders, they are unable to find enough food for the lean season which results in transitory food insecurity. Secondly, in the long term, the environmental impacts of wildfires on the soil lead to lower yields and inadequate food to meet household nutritional needs. Farmers then deploy certain strategies such as early-harvesting and switching to early-maturing crops to avoid with the perennial fires and these strategies further reinforce other dimensions of food insecurity such as nutrition insecurity. Because livelihoods strategies such as crop farming, hunting, charcoal production and herding intersect in the northern savannah zone, we recommend policy options that will engage community members in finding common ways of using shared spaces sustainably. Government should also adopt policies that will encourage domestication of certain livelihood strategies such as cattle herding.     

Body mass and parental decisions in the Antarctic petrel Thalassoica antarctica : how long should the parents guard the chick?

In Procellariiformes, the parents guard the chick after it has attained homeothermy. This strategy may reduce the probability that a small chick is taken by predators, but is costly as only one parent can forage at a time. The decision to leave the chick may therefore be a compromise between the chick's vulnerability to predators, the body condition of the parent on the nest and whether the foraging parent returns in time. We studied how the number of days that parents guarded the chick was related to the body mass of the parent at the nest and the time the foraging parent spent at sea in the Antarctic petrel Thalassoica antarctica. We also examined how the body mass of the parent on the nest and the duration of the foraging trips influenced the chicks' body condition at the end of the guarding period. When the foraging parent did not return to the nest in time to relieve its mate, the number of days the parent on the nest kept guarding the chick was positively related to its body mass on arrival in the colony. The number of days the foraging parent spent at sea was positively related to the body mass of its mate, but those that returned in time had a shorter stay at sea relative to their mate's body mass than those that did not return before their mate had left. Apparently, both the body mass of the parent at the nest and the ability of the foraging parent to adjust its stay at sea to the mate's body mass is important for the number of days the parents guard the chick and also the chick's body condition at this point. The inability to return to the nest before the mate has left may be the result of needing a minimum amount of time at sea to find food, or because some parents having low foraging success and therefore prolong their stay at sea. Received: 10 October 1997 / Accepted after revision: 14 March 1998     

Preserving the maritime cultural heritage of the Mediterranean,a cradle of cultures,religions and civilizations—the holy land perspective

The article presents the main ancient marine sites of the Holy Land, points the endangered sites and the needed preservation activities. The ancient cultural heritage existing on the Mediterranean shores reflect important events in the history of humanity. It represents numerous important cultures, religions and traditions. This coastal and underwater heritage is rapidly eroded due to sea level rise, global changes and rapid coastal development. Actions taken by the state of Israel to rescue, protect and preserve the marine cultural heritage include: underwater rescue surveys, coastal erosion monitoring, risk assessment surveys and pilot projects for protecting and preserving the sea front of the antique sites at Akko, Apollonia and Ashkelon. Israel proposes that the Mediterranean and European countries will establish a collaborative project aimed at mapping the cultural recourses and establishing master plans for the protection and preservation of the marine and coastal cultural heritage of the Mediterranean.     

Will the COVID-19 pandemic end with the Delta and Omicron variants?

Environmental Chemistry Letters -     

Extension of the skin shear stress Li’s relationship to the flat bed

A proper estimation of the skin shear stress τ _s is necessary for a proper evaluation of sediment flux at the sediment–fluid interface. Several empirical formulas of the skin shear stress have been proposed in the literature for rippled bed as function of the factor form η/λ (η and λ are respectively the height and wavelength of the bedform). These formulas express that in the presence of bedform, τ _s is a partition of the total shear stress τ _b . In contrast, when the bottom is flat, τ _s is exactly equal to τ _b . Based on in situ measurements, Li (J Geophys Res 99:791–799, 1994) has proposed a new formula of τ _s depending on u _*/η (u _* is the friction velocity, ${u_{*}=\sqrt{\tau_{b}/\rho}}$ ), but not as a function of η/λ. This formulation appears physically more realistic, but does not cover the flat bottom range. The purpose of this short note is therefore the extension of the Li’s expression to this type of bottom.