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121.
David W. Kikuchi William L. Allen Kevin Arbuckle Thomas G. Aubier Emmanuelle S. Briolat Emily R. Burdfield-Steel Karen L. Cheney Klára Daňková Marianne Elias Liisa Hämäläinen Marie E. Herberstein Thomas J. Hossie Mathieu Joron Krushnamegh Kunte Brian C. Leavell Carita Lindstedt Ugo Lorioux-Chevalier Melanie McClure Callum F. McLellan Iliana Medina Viraj Nawge Erika Páez Arka Pal Stano Pekár Olivier Penacchio Jan Raška Tom Reader Bibiana Rojas Katja H. Rönkä Daniela C. Rößler Candy Rowe Hannah M. Rowland Arlety Roy Kaitlin A. Schaal Thomas N. Sherratt John Skelhorn Hannah R. Smart Ted Stankowich Amanda M. Stefan Kyle Summers Christopher H. Taylor Rose Thorogood Kate Umbers Anne E. Winters Justin Yeager Alice Exnerová 《Journal of evolutionary biology》2023,36(7):975-991
Prey seldom rely on a single type of antipredator defence, often using multiple defences to avoid predation. In many cases, selection in different contexts may favour the evolution of multiple defences in a prey. However, a prey may use multiple defences to protect itself during a single predator encounter. Such “defence portfolios” that defend prey against a single instance of predation are distributed across and within successive stages of the predation sequence (encounter, detection, identification, approach (attack), subjugation and consumption). We contend that at present, our understanding of defence portfolio evolution is incomplete, and seen from the fragmentary perspective of specific sensory systems (e.g., visual) or specific types of defences (especially aposematism). In this review, we aim to build a comprehensive framework for conceptualizing the evolution of multiple prey defences, beginning with hypotheses for the evolution of multiple defences in general, and defence portfolios in particular. We then examine idealized models of resource trade-offs and functional interactions between traits, along with evidence supporting them. We find that defence portfolios are constrained by resource allocation to other aspects of life history, as well as functional incompatibilities between different defences. We also find that selection is likely to favour combinations of defences that have synergistic effects on predator behaviour and prey survival. Next, we examine specific aspects of prey ecology, genetics and development, and predator cognition that modify the predictions of current hypotheses or introduce competing hypotheses. We outline schema for gathering data on the distribution of prey defences across species and geography, determining how multiple defences are produced, and testing the proximate mechanisms by which multiple prey defences impact predator behaviour. Adopting these approaches will strengthen our understanding of multiple defensive strategies. 相似文献
122.
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124.
Saidi Y Finka A Chakhporanian M Zrÿd JP Schaefer DG Goloubinoff P 《Plant molecular biology》2005,59(5):697-711
The ability to express tightly controlled amounts of endogenous and recombinant proteins in plant cells is an essential tool
for research and biotechnology. Here, the inducibility of the soybean heat-shock Gmhsp17.3B promoter was addressed in the moss Physcomitrella patens, using β-glucuronidase (GUS) and an F-actin marker (GFP-talin) as reporter proteins. In stably transformed moss lines, Gmhsp17.3B-driven GUS expression was extremely low at 25 °C. In contrast, a short non-damaging heat-treatment at 38 °C rapidly induced
reporter expression over three orders of magnitude, enabling GUS accumulation and the labelling of F-actin cytoskeleton in
all cell types and tissues. Induction levels were tightly proportional to the temperature and duration of the heat treatment,
allowing fine-tuning of protein expression. Repeated heating/cooling cycles led to the massive GUS accumulation, up to 2.3%
of the total soluble proteins. The anti-inflammatory drug acetyl salicylic acid (ASA) and the membrane-fluidiser benzyl alcohol
(BA) also induced GUS expression at 25 °C, allowing the production of recombinant proteins without heat-treatment. The Gmhsp17.3B promoter thus provides a reliable versatile conditional promoter for the controlled expression of recombinant proteins in
the moss P. patens. 相似文献
125.
Dianna K. Padilla 《Evolutionary ecology》1993,7(6):634-644
Summary Structural features of marine macrophytes are generally believed to act as defences against herbivores by reducing the ability of herbivores to consume the plants. Thallus form and calcification in particular have been considered structural defences that act by reducing the probability of consumption of tissue by herbivores. Studies directly measuring the mechanical resistance of a variety of marine algae (tropical and temperate) to herbivores of two important feeding types, rasping herbivores (docoglossan limpets) and a biting herbivore (an herbivorous crab), do not support this hypothesis. I suggest that thallus form and calcification may play a more important role in minimizing the impact of herbivores by reducing the probability of subsequent tissue loss due to herbivore-induced damage. For some algal species, tissue lost subsequent to herbivore damage may greatly exceed loss due to direct consumption by herbivores. I suggest that calcification and thallus properties resulting in preferential tear directions reduce the probability of tissue loss subsequent to herbivore damage rather than prevent herbivores from removing tissue as has been suggested in the past. 相似文献
126.
Mechanism of a plastic phenotypic response: predator-induced shell thickening in the intertidal gastropod Littorina obtusata 总被引:1,自引:0,他引:1
Phenotypic plasticity has been the object of considerable interest over the past several decades, but in few cases are mechanisms underlying plastic responses well understood. For example, it is unclear whether predator-induced changes in gastropod shell morphology represent an active physiological response or a by-product of reduced feeding. We address this question by manipulating feeding and growth of intertidal snails, Littorina obtusata, using two approaches: (i) exposure to predation cues from green crabs Carcinus maenas and (ii) reduced food availability, and quantifying growth in shell length, shell mass, and body mass, as well as production of faecal material and shell micro-structural characteristics (mineralogy and organic fraction) after 96 days. We demonstrate that L. obtusata actively increases calcification rate in response to predation threat, and that this response entails energetic and developmental costs. That this induced response is not strictly tied to the animal's behaviour should enhance its evolutionary potential. 相似文献
127.
电针诱导心肌缺血大鼠延髓头端腹外侧区nNOS和iNOS差异表达 总被引:1,自引:0,他引:1
许多研究表明,延髓头端腹外侧区(rostral ventrolateml medulla,RVLM)的NO/NOS系统参与心血管活动的中枢调节.本实验以结扎Wistar大鼠左冠状动脉前降支法建立急性心肌缺血(acute myocardial ischemia,AMI)动物模型,观察针刺"内关"穴改善AMI大鼠的心功能作用,同时检测大鼠RVLM区神经元型一氧化氮合酶(neuronal nitric oxide synthase,nNOS)和诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)表达的变化,进而探讨针刺治疗AMI的中枢机制.实验观察显示,AMI大鼠心功能各项指标减弱,伴随外周血去甲肾上腺素(norepinephrine,NE)和脑钠肽(brain natriuretic peptide,BNP)水平显著升高,同时RVLM区nNOS阳性神经元数和nNOS mRNA表达升高,而iNOS水平则降低.针刺"内关"穴(Pe 6)(每天30 min,连续5天)改善心功能,降低AMI大鼠血清中NE和BNP的水平,同时升高iNOS并降低nNOS在RVLM的表达.以上结果提示,针刺治疗心肌缺血的同时可以调节iNOS/NO和nNOS/NO在RVLM的变化,这可能与针刺通过调节RVLM区的NO含量进而降低交感传出,从而改善AMI大鼠的心功能有关. 相似文献
128.
JOHN SKELHORN HANNAH M. ROWLAND GRAEME D. RUXTON 《Biological journal of the Linnean Society. Linnean Society of London》2010,99(1):1-8
Many organisms appear to mimic inanimate objects such as twigs, leaves, stones, and bird droppings. Such adaptations are considered to have evolved because their bearers are misidentified as either inedible objects by their predators, or as innocuous objects by their prey. In the past, this phenomenon has been classified by some as Batesian mimicry and by others as crypsis, but now is considered to be conceptually different from both, and has been termed ‘masquerade’. Despite the debate over how to classify masquerade, this phenomenon has received little attention from evolutionary biologists. Here, we discuss the limited empirical evidence supporting the idea that masquerade functions to cause misidentification of organisms, provide a testable definition of masquerade, and suggest how masquerade evolved and under what ecological conditions. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 1–8. 相似文献
129.
Ernesto Gianoli Sebastián Sendoya Fernando Vargas Paula Mejía Rodolfo Jaffé Mayanín Rodríguez Adrián Gutiérrez 《Ecological Research》2008,23(5):905-908
Optimal defence theory (ODT) predicts that, whereas high risk of herbivory should select for high constitutive levels of defence,
induced defences should be more advantageous in environments with a low probability of herbivory. In the present field study,
conducted on the Azteca–Cecropia ant–plant system in a Neotropical rainforest, we evaluated whether the constitutive and induced ant defence of leaves are
directly and inversely related to an estimate of herbivory risk, respectively. To assess the constitutive level of Azteca defence in Cecropia obtusifolia trees, we recorded the number of ants patrolling undamaged leaves. To evaluate the induced level of Azteca defence, the same leaves were subjected to simulated herbivory by punching circular holes in them. We recorded the maximum
number of ants patrolling the damaged leaves from 2 to 15 min after damage. Past herbivory (% defoliation of old leaves) was
assumed to indicate a risk of herbivory. Regression analyses showed that, whereas the constitutive level of ant patrolling
was positively associated with the magnitude of herbivory on old leaves, there was a negative association between the magnitude
of induced ant defence and past herbivory. These preliminary results lend support to ODT. 相似文献
130.
David Charifson 《Invertebrate Biology》2019,138(4)
A laboratory experiment was conducted with the marine gastropod Littorina littorea from three different sites in Long Island Sound to test for inducible responses to the non‐native predatory crab Hemigrapsus sanguineus. Individuals of L. littorea did not exhibit decreased shell growth in response to increased predation risk, which differs from the response seen in other species of Littorina. However, snails did exhibit slower growth in response to reduced food availability, as seen in other gastropods. Surprisingly, snails from two sites exhibited differences between the crab‐exposed and reduced food‐availability treatments in how they remodeled the thickness of different microstructural layers of shell material in apical parts of the shell. Although individuals of L. littorea did not show the typical shell thickening response seen in other gastropods, they did show differences among populations in remodeling their shell. This underlies the importance of examining how the shell is constructed and remodeled in studies of inducible defenses in gastropods, as well as the importance of examining animals from multiple populations. 相似文献