We conducted an intensive review of conservation science to find out whether the field has tracked priorities over the past 20 years. A total of 628 papers from the literature, for the years 1984, 1994, and 2004, were surveyed. For each paper, we recorded where conservation research was done and what was studied. We found geographic gaps in conservation research, with marine, tundra, and desert biomes being studied less than other systems. We also found taxonomic gaps, with amphibians being understudied as compared to other, less threatened, taxonomic groups. Finally, we discovered that studies of invasive species are still lacking, despite the magnitude of the threat they pose to global biodiversity. Although there was a weak trend towards filling these gaps between 1984 and 2004, progress has been slow. To be more effective, the research community must quickly redirect research to better match conservation priorities.
Leadership is a critical tool for expanding the influence of conservation science, but recent advances in leadership concepts and practice remain underutilized by conservation scientists. Furthermore, an explicit conceptual foundation and definition of leadership in conservation science are not available in the literature. Here we drew on our diverse leadership experiences, our reading of leadership literature, and discussions with selected conservation science leaders to define conservation-science leadership, summarize an exploratory set of leadership principles that are applicable to conservation science, and recommend actions to expand leadership capacity among conservation scientists and practitioners. We define 2 types of conservation-science leadership: shaping conservation science through path-breaking research, and advancing the integration of conservation science into policy, management, and society at large. We focused on the second, integrative type of leadership because we believe it presents the greatest opportunity for improving conservation effectiveness. We identified 8 leadership principles derived mainly from the "adaptive leadership" literature: recognize the social dimension of the problem; cycle frequently through action and reflection; get and maintain attention; combine strengths of multiple leaders; extend your reach through networks of relationships; strategically time your effort; nurture productive conflict; and cultivate diversity. Conservation scientists and practitioners should strive to develop themselves as leaders, and the Society for Conservation Biology, conservation organizations, and academia should support this effort through professional development, mentoring, teaching, and research.
Summary 1.Aposematism is a widely used antipredator strategy in which an organism possesses both warning coloration and unprofitable characters. Theoretical evidence suggests that aposematic colour should develop when high opportunity costs imposed by crypsis force an organism to engage in conspicuous behaviours. Hence, it is expected that ontogenetic colour change (OCC) in larval insects should include aposematism when foraging needs compel behavioural modifications that preclude a continued state of crypsis. 2. To test this idea, I first investigated whether OCC in caterpillars of the panic moth Saucrobotys futilalis was indicative of a switch from cryptic to aposematic coloration. I then examined the context of panic moth OCC as it related to foraging patterns and behavioural conspicuousness. 3. Early Saucrobotys instars are a cryptic green, but later instars become progressively more orange and develop black spots. Early instar larvae forage cryptically on the inner parenchyma of silked-together host plant leaves to avoid predation, but are rapidly forced to engage in conspicuous foraging behaviours as they outgrow the resources afforded by their shelters. Both coloration and behaviour reach maximal conspicuousness in final instar larvae. 4. As predicted, OCC encompassed a change from crypsis to aposematism in Saucrobotys . Aposematic function was demonstrated by changes in both antipredator behaviour patterns and effectiveness of predator deterrence in early and late instars. Moreover, increased opportunity costs of crypsis and behavioural conspicuousness coincided with the onset of aposematic coloration. 5. This pattern of OCC suggests that aposematic coloration in Saucrobotys develops as a response to constraints imposed by crypsis. Moreover, my study illustrates the importance of the study of ontogenetic patterns in determining how behaviour, morphology, and predator responses interact to influence the initial evolution of phenomena such as aposematism.
Pinoresinol, a lignan of wide distribution in plants, is found to occur as a minor component in the defensive secretion produced by glandular hairs of caterpillars of the cabbage butterfly, Pieris rapae. The compound or a derivative is appropriated by the larva from its normal food plant (the cabbage, Brassica oleracea). Pinoresinol was shown to be absent from the secretion if the larva was given a cabbage-free diet but present in the effluent if that diet was supplemented with pinoresinol. Pinoresinol is shown to be a feeding deterrent to ants (Formica exsectoides), indicating that it can complement the defensive action of the primary components of the secretion, a set of previously reported lipids called mayolenes. In the test with F. exsectoides, pinoresinol proved to be more potent than concomitantly tested mayolene-16.ignans comprise a large class of secondary metabolites in vascular plants. Derived from the three phenyl-propanoid precursors, p-coumaryl alcohol (1 in Fig. 1), coniferyl alcohol (2 in Fig. 1) and sinapyl alcohol (3 in Fig. 1), they fulfill important physiological functions in plants (1) and are of considerable pharmaceutical interest (2). For example, podophyllotoxin (4 in Fig. 1) derivatives are used extensively in anticancer treatments and have been shown recently to possess antiviral properties as well (3). Pinoresinol (5 in Fig. 1) is one of the structurally simplest lignans, being a dimer of coniferyl alcohol, and its frequent presence in woody or fibrous plants should come as no surprise [the Beilstein database (MDL Information Systems, San Leandro, CA) revealed 46 and 8 references, respectively, for the isolation of (ϩ)-pinoresinol and (Ϫ)-pinoresinol from plants] (4). Virtually any plant capable of producing lignin can be presumed to have the enzymes necessary to link two units of coniferyl alcohol (2 in Fig. 1) in a fashion leading to the bicyclic ring core of pinoresinol (5 in Fig. 1).The amount of pinoresinol produced by plants varies widely. Particularly high concentrations of pinoresinol have been found in young foliage, for example of Forsythia spp., as well as in the reproductive organs and seeds of many plants (5). The compound is therefore generally presumed to be a defensive agent, as is suggested also by its antihelminthic and antifungal activity (6-9). Animals are not known to produce pinoresinol or other dimeric lignols, nor have they been shown to acquire such compounds from plants. We here report the presence of pinoresinol in the defensive secretion of a caterpillar, the larva of Pieris rapae, the cabbage butterfly, one of the world's most familiar lepidopterans (10). We had earlier reported on the composition of this secretion, produced as droplets by glandular hairs on the back and flanks of the larva (11) (Fig. 2). We had noted the fluid to contain a series of structurally labile linolenic acid derivatives, the mayolenes (6 in Fig. 3), which we demonstrated to be protective against ants (Crematogaster lineolata) (11). We have found pinoresinol itself to also be dete...
Extensive chemical analyses of spider venoms from many species have revealed complex mixtures of biologically active compounds, of which several have provided important leads for drug development. We have recently shown that NMR spectroscopy can be used advantageously for a direct structural characterization of the small-molecule content of such complex mixtures. Here, we report the application of this strategy to a larger-scale analysis of a collection of spider venoms representing >70 species, which, in combination with mass spectrometric analyses, allowed the identification of a wide range of known, and several previously undescribed, small molecules. These include polyamines, common neurotransmitters, and amino acid derivatives as well as two additional members of a recently discovered family of natural products, the sulfated nucleosides. In the case of the well studied brown recluse spider, Loxosceles reclusa, sulfated guanosine derivatives were found to comprise the major small-molecule components of the venom. chemical prospecting ͉ Loxosceles ͉ metabolomics ͉ natural products ͉ neurotoxins
SUMMARY The relationship between insect gut structure and foraging strategy has been studied for several hundred years; however, we know little about how, or even if, other common insect behaviors are linked to gut morphology. For example, many insects defend themselves by regurgitation, a behavior which is expected to be closely connected to gut structure. Caterpillars belong to an insect taxon, the Lepidoptera, with a particularly well-studied digestive tract and a known predilection for defensive regurgitation. I have explored whether defensive regurgitation is associated with specific gut structure by examining the relationship between defensive behavior and gut morphology in the larvae of 36 butterfly and moth species. My analysis shows that predilection to defensively regurgitate is closely associated with fore- and midgut morphology. Species that primarily regurgitate in defense have enlarged foreguts and shortened midguts, whereas the opposite relationship is seen among those that do not readily regurgitate. These results reveal that: (i)defensive regurgitation is not the primary defense of all caterpillars, and(ii) gut morphology can be associated with other factors than the chemical and mechanical properties of ingested foods. These findings challenge long held beliefs concerning the ubiquity of defensive regurgitation in caterpillars and the causes of diversification of gut morphology, and further reinforce the gut's standing as a complex and sophisticated organ.
Beetles of the family Lycidae have long been known to be chemically protected. We present evidence that North American species of the lycid genera Calopteron and Lycus are rejected by thrushes, wolf spiders, and orb-weaving spiders, and that they contain a systemic compound that could account, at least in part, for this unacceptability. This compound, a novel acetylenic acid that we named lycidic acid, proved actively deterrent in feeding tests with wolf spiders and coccinellid beetles.Species of Lycus commonly figure as models of mimetic associations. Among their mimics are species of the cerambycid beetle genus Elytroleptus, remarkable because they prey upon the model lycids. We postulated that by doing so Elytroleptus might incorporate the lycidic acid from their prey for their own defense. However, judging from analytical data, the beetles practice no such sequestration, explaining why they remain relatively palatable (in tests with wolf spiders) even after having fed on lycids. Chemical analyses also showed the lycids to contain pyrazines, such as were already known from other Lycidae, potent odorants that could serve in an aposematic capacity to forestall predatory attacks.
Widespread and intensive application of road deicers, primarily road salt (NaCl), in North America threatens water quality and the health of freshwater ecosystems. Intensive use of NaCl can be harmful to sensitive members of freshwater ecosystems such as amphibians. Detection of negative effects of NaCl application has prompted the search for alternative chemical deicers with lower environmental impacts. We conducted a series of 96-h acute toxicity tests to determine the negative sensitivity of larval wood frogs (Rana [Lithobates] sylvatica) to six deicing chemicals: urea (CH(4) N(2) O), sodium chloride (NaCl), magnesium chloride (MgCl(2) ), potassium acetate (CH(3) COOK), calcium chloride (CaCl(2) ), and calcium magnesium acetate (C(8) H(12) CaMgO(8) ). Acetates are sometimes touted as environmentally friendly alternatives to NaCl but have not been examined in enough detail to warrant this designation. When exposed to a range of environmentally realistic concentrations of these chemicals, larvae were least sensitive (i.e., had the lowest mortality rate) to CH(4) N(2) O, NaCl, and MgCl(2) and most sensitive to acetates (C(8) H(12) CaMgO(8) , CH(3) COOK) and CaCl(2) . Our observed median lethal concentration estimates (LC50(96-h) ) for NaCl were over two times higher than values presented in previous studies, which suggests variability in tolerance among R. sylvatica populations. The deicers varied greatly in their toxicity, and further research is warranted to examine the differential effects of this suite of deicers on other species.
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