Susana Clusella-Trullas

Susana Clusella-Trullas
Stellenbosch University | SUN · Department of Botany and Zoology

PhD

About

91
Publications
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4,417
Citations

Publications

Publications (91)
Article
Full-text available
While essential in understanding impacts of climate change for organisms, diel variation remains an understudied component of temporal variation in thermal tolerance limits [i.e. the critical thermal minimum (CTmin) and maximum (CTmax)]. For example, a higher Ctmax might be expected for an individual if the measurement is taken during the day (when...
Article
Full-text available
Birds exhibit wide variation in their use of aquatic environments, on a spectrum from entirely terrestrial, through amphibious, to highly aquatic. Although there are limited empirical data on hearing sensitivity of birds underwater, mounting evidence indicates that diving birds detect and respond to sound underwater, suggesting that some modificati...
Article
Nest care and brooding in sunbirds (Nectariniidae) is thought to be performed exclusively by females. Here, we provide the first evidence that male sunbirds might help with brooding. During a ringing session in Hoekwil, South Africa, we observed one male Amethyst Sunbird (Chalcomitra amethystina) with a brood patch. Its sex was confirmed using mole...
Article
Full-text available
The impact of climate change on global biodiversity is firmly established, but the differential effect of climate change on populations within the same species is rarely considered. In ectotherms, melanism (i.e. darker integument due to heavier deposition of melanin) can significantly influence thermoregulation, as dark individuals generally heat m...
Article
Full-text available
Seabirds are amongst the most mobile of all animal species and spend large amounts of their lives at sea. They cross vast areas of ocean that appear superficially featureless, and our understanding of the mechanisms that they use for navigation remains incomplete, especially in terms of available cues. In particular, several large-scale navigationa...
Article
To forecast climate change impacts across habitats or taxa, thermal vulnerability indices (e.g., safety margins and warming tolerances) are growing in popularity. Here, we present their history, context, formulation, and current applications. We highlight discrepancies in terminology and usage, and we draw attention to key assumptions underpinning...
Article
Thermal adaptation theory posits that variation of thermal traits such as those affecting thermal budgets and the performance of ectotherms should be associated with climate gradients. Under a simple scenario, thermal traits should also co-vary to shape optimal thermal phenotypes under a particular climate. However, geographical variation and covar...
Article
Full-text available
1. Climate affects all aspects of biology. Physiological traits play a key role in mediating these effects, because they define the fundamental niche of each organism. 2. Climate change is likely to shift environmental conditions away from physiological optima. The consequences for species are significant: they must alter their physiology through p...
Article
With functions as diverse as communication, protection and thermoregulation, colouration is one of the most important traits in lizards. The ability to change colour as a function of varying social and environmental conditions is thus an important innovation. While colour change is present in animals ranging from squids, to fish and reptiles, not m...
Article
Full-text available
Understanding how species’ thermal limits have evolved across the tree of life is central to predicting species’ responses to climate change. Here, using experimentally-derived estimates of thermal tolerance limits for over 2000 terrestrial and aquatic species, we show that most of the variation in thermal tolerance can be attributed to a combinati...
Article
Full-text available
The fitness consequences of thermal plasticity of functional traits of insects, and the life stages at which these responses manifest, remain a subject of much debate. Here, we examine whether a short-term exposure to cold, medium or warm fluctuating temperature regimes during development (larval or adult) affects adult performance, thermal toleran...
Article
Full-text available
In a highly dynamic airspace, flying animals are predicted to adjust foraging behaviour to variable wind conditions to minimize movement costs. Sexual size dimorphism is widespread in wild animal populations, and for large soaring birds which rely on favourable winds for energy‐efficient flight, differences in morphology, wing loading and associate...
Article
Insects have been influential models in research on color variation, its evolutionary drivers and the mechanistic basis of such variation. More recently, several studies have indicated that insect color is responding to rapid climate change. However, it remains challenging to ascertain drivers of color variation among populations and species, and a...
Article
The perception of airborne infrasound (sounds below 20 Hz, inaudible to humans except at very high levels) has been documented in a handful of mammals and birds. While animals that produce vocalizations with infrasonic components (e.g. elephants) present conspicuous examples of potential use of infrasound in the context of communication, the extent...
Chapter
Full-text available
Ecological interactions, especially those that are beneficial (i.e. mutualism) or detrimental (i.e. parasitism), play important roles during the establishment and spread of alien species. This chapter explores the role of these interactions during biological invasions in South Africa, covering a wide range of taxonomic groups and interaction types....
Article
Full-text available
A classic question in evolutionary biology is whether behavioral flexibility hastens or hinders evolutionary change. The latter idea, that behavior reduces the number of environmental states experienced by an organism and buffers that organism against selection, has been dubbed the “Bogert Effect” after Charles Bogert, the biologist who first popul...
Article
What makes some species successful invaders while others fail, and why some invaders have major impacts in invaded ecosystems are pivotal questions that are attracting major research effort. The increasing availability of high resolution, georeferenced stable isotope landscapes (‘isoscapes'), coupled with the commercialization of stable isotope‐enr...
Article
Full-text available
Although the impacts of climate change and invasive species are typically studied in isolation, they likely interact to reduce the viability of plant and animal populations. Indeed, invasive species, by definition, have succeeded in areas outside of their native range, and may therefore have higher adaptive capacity relative to native species. Neve...
Article
Full-text available
The advent of miniaturized biologging devices has provided ecologists with unprecedented opportunities to record animal movement across scales, and led to the collection of ever‐increasing quantities of tracking data. In parallel, sophisticated tools have been developed to process, visualize and analyse tracking data, however many of these tools ha...
Article
A growing body of research demonstrates the impacts of invasive alien plants on native animals, but few studies consider thermal effects as a driver of the responses of native organisms. As invasive alien plants establish and alter the composition and arrangement of plant communities, the thermal landscapes available to ectotherms also change. Our...
Article
Linking variation in species' traits to large-scale environmental gradients can lend insight into the evolutionary processes that have shaped functional diversity and future responses to environmental change. Here, we ask how heat and cold tolerance vary as a function of latitude, elevation and climate extremes, using an extensive global dataset of...
Article
Full-text available
Laboratory measurements of physiological and demographic tolerances are important to understanding the impact of climate change on species diversity; however, it has been recognized that forecasts based solely on these laboratory estimates overestimate risk by omitting the capacity for species to utilize microclimatic variation via behavioral adjus...
Article
Processing food (e.g. ingestion, digestion, assimilation) requires energy referred to as specific dynamic action (SDA) and is at least partially fuelled by oxidation of the nutrients (e.g. proteins and lipids) within the recently ingested meal. In ectotherms, environmental temperature can affect the magnitude and/or duration of the SDA, but is like...
Article
Ecologists often use indices or proxies to communicate complex ecological entities. Indices commonly known as thermal safety margin, habitat thermal quality and hours of restriction describe species’ vulnerability to climate change by comparing organisms’ thermal limits or preferences to available habitat temperatures. Ready access to temperature d...
Preprint
Full-text available
The advent of miniaturized biologging devices has provided ecologists with unparalleled opportunities to record animal movement across scales, and led to the collection of ever-increasing quantities of tracking data. In parallel, sophisticated tools to process, visualize and analyze tracking data have been developed in abundance. Within the R softw...
Article
Aim To determine whether recent range expansion of small‐bodied arboreal frogs, Hyperolius marmoratus Rapp, is accompanied by changes in species–environment relationships and whether its historical range was constrained by climate, availability of water bodies or topographic variables. We test if artificial water bodies in the novel range have faci...
Article
The spatial scale at which climate and species’ occupancy data are gathered, and the resolution at which ecological models are run, can strongly influence predictions of species performance and distributions. Running model simulations at coarse rather than fine spatial resolutions, for example, can determine if a model accurately predicted the dist...
Article
The precision and the extent of behavioral thermoregulation are likely to provide fitness benefits to ectotherms. Yet the factors driving variation in selected or preferred body temperature (Tset) and its usefulness as a proxy for optimal physiological temperature (Topt) are still debated. Although Tset is often conserved among closely related spec...
Article
Full-text available
How climate affects species distributions is a longstanding question receiving renewed interest owing to the need to predict the impacts of global warming on biodiversity. Is climate change forcing species to live near their critical thermal limits? Are these limits likely to change through natural selection? These and other important questions can...
Article
Full-text available
The visible spectrum represents a fraction of the sun’s radiation, a large portion of which is within the near infrared (NIR). However, wavelengths outside of the visible spectrum that are reflected by coloured tissues have rarely been considered, despite their potential significance to thermal effects. Here, we report the reflectivity from 300 to...
Article
The importance of colour for temperature regulation in animals remains controversial. Colour can affect an animal's temperature because all else being equal, dark surfaces absorb more solar energy than do light surfaces, and that energy is converted into heat. However, in reality, the relationship between colour and thermoregulation is complex and...
Article
Nutritional deprivation or desiccation can influence thermal tolerance by impacting the insects' ability to evaporatively cool, maintain cell membrane integrity and conduct protective or repair processes. Recovery from chilling is also linked to the re-establishment of iono- and osmo-regulatory homeostasis. Here, using Mediterranean fruit fly (Cera...
Article
Full-text available
Harmonia axyridis (Coleoptera: Coccinellidae) has been introduced widely for biological control of agricultural pests. Harmonia axyridis has established in four continents outside of its native range in Asia and it is considered an invasive alien species (IAS). Despite a large body of work on invasion ecology, establishment mechanisms of IAS and th...
Article
Full-text available
Background: Increasing numbers of invasive alien plant (IAP) species are establishing around the globe and can have negative effects on resident animal species function and diversity. These impacts depend on a variety of factors, including the extent of invasion, the region and the taxonomic group affected. These context dependencies make extrapola...
Article
Full-text available
Increasing numbers of invasive plant species are establishing around the globe, and these species frequently form dense stands that alter habitat structure in critical ways. Nevertheless, little is known about the mechanisms underlying the impacts of invasive alien plant species on native fauna. We first ask whether alien pine trees impact lizard s...
Article
Full-text available
Critical thermal limits form an increasing component of the estimation of impacts of global change on ectotherms. Whether any consistent patterns exist in the interactive effects of rates of temperature change (or experimental ramping rates) and acclimation on critical thermal limits and warming tolerance (one way of assessing sensitivity to climat...
Article
Full-text available
The theory of thermoregulation has developed slowly, hampering efforts to predict how individuals can buffer climate change through behaviour. Mixed results of field and laboratory experiments underscore the need to test hypotheses about thermoregulation explicitly, while measuring costs and benefits in different thermal landscapes. 2.We simulated...
Article
The energetics of processing a meal is crucial for understanding energy budgets of animals in the wild. Given that digestion and its associated costs may be dependent on environmental conditions, it is crucial to obtain a better understanding of these costs under diverse conditions and identify resulting behavioural or physiological trade-offs. Thi...
Article
Full-text available
Climate change affects the rate of insect invasions as well as the abundance, distribution and impacts of such invasions on a global scale. Among the principal analytical approaches to predicting and understanding future impacts of biological invasions are Species Distribution Models (SDMs), typically in the form of correlative Ecological Niche Mod...
Article
Full-text available
The harlequin ladybird, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), is native to Asia but has been intentionally introduced to many countries as a biological control agent of pest insects. In numerous countries, however, it has been introduced unintentionally. The dramatic spread of H. axyridis within many countries has been met with co...
Article
Although isopod crustaceans frequently show sexual dimorphism in body size, sexual differences in other non-reproductive (secondary sexual) traits have been rarely studied. Furthermore, little is known about the physiological correlates of variation in the expression of sexually dimorphic traits in animals generally. Here, we show that the unusual...
Article
Full-text available
Hesperomyces virescens is a fungal ectoparasite (Laboulbeniales) that infects adult ladybirds. Research has recently focused on this parasite due to the discovery of its prevalence on the globally invasive harlequin ladybird Harmonia axyridis and for its potential use in studies of co-evolution and pathogen spread. We collected adults from ten spec...
Conference Paper
Evolutionary adaptation of the ‘thermal performance curve’ (TPC) to changes in the thermal environment may be an important avenue by which ectotherms can avoid extinction in the face of climate change. Indeed, studies have shown that many populations have sufficient phenotypic variation in TPCs, and that selection can target them when the environme...
Article
Phenotypic plasticity may buffer the selection pressures on organisms that inhabit novel or rapidly-changing environments. We investigated plasticity of thermal tolerance, energetic and water loss traits and their interaction with behaviour in a small-bodied, arboreal anuran (Hyperolius marmoratus Rapp, Hyperoliidae) undergoing rapid range expansio...
Article
Environmental variability occurring at different timescales can significantly reduce performance, resulting in evolutionary fitness costs. Shifts in thermoregulatory behavior, metabolism, and water loss via phenotypic plasticity can compensate for thermal variation, but the relative contribution of each mechanism and how they may influence each oth...
Article
Full-text available
Desert resource environments (e.g., microclimates, food) are tied to limited, highly localized rainfall regimes which generate microgeographic variation in the life histories of inhabitants. Typically, enhanced growth rates, reproduction and survivorship are observed in response to increased resource availability in a variety of desert plants and s...
Article
The influence of thermal history on temperature-dependent flight performance was investigated in an invasive agricultural pest insect, Ceratitis capitata (Diptera: Tephritidae). Flies were exposed to one of four developmental acclimation temperatures (Tacc: 15, 20, 25, 30°C) during their pupal stage and tested at these temperatures (Ttest) as adult...
Article
Full-text available
This study examined high temperature survival and heat shock protein 70 (Hsp70) responses to temperature variation for two marine invertebrate species on sub-Antarctic Marion Island. The isopod Exosphaeroma gigas Leach and the amphipod Hyale hirtipalma Dana had the same tolerance to high temperature. The mean upper temperature which was lethal for...
Article
Full-text available
The weevil Cyrtobagous salviniae Calder & Sands 1985 (Family: Curculionidae) is a highly effective biocontrol agent for the invasive water fern Salvinia molesta D.S. Mitchell (Family: Salviniaceae). The life histories of both organisms are affected by temperature, making the potential impacts of climate change on efficacy of control an important ar...
Article
Physiological responses to transient conditions may result in costly responses with little fitness benefits, and therefore, a trade-off must exist between the speed of response and the duration of exposure to new conditions. Here, using the puparia of an important insect disease vector, Glossina pallidipes, we examine this potential trade-off using...
Article
Climate change is expected to drive range shifts among a wide array of organisms. Non-indigenous species (NIS) provide a unique opportunity to observe the establishment of range boundaries in a way that cannot be directly seen for native species. Recent studies have indicated that climate change facilitates biological invasions at local scales. How...
Article
Understanding the extent to which organisms are affected by climate change and are capable of adapting to warming is essential for managing biodiversity. Recent macrophysiological analyses suggest that range-related responses to warming may be more coherent (less variable) and predictable in marine than in terrestrial systems.To examine this genera...
Article
Full-text available
Thermal trait variation is of fundamental importance to forecasting the impacts of environmental change on lizard diversity. Here, we review the literature for patterns of variation in traits of upper and lower sub-lethal temperature limits, temperature preference and active body temperature in the field, in relation to space, time and phylogeny. T...
Article
Full-text available
Several reasons have been proposed for animal aggregation, including energy or water conservation. However, the latter physiological hypotheses have not been well investigated. Here, we report the effects of aggregation on metabolic (VCO2) and evaporative water-loss rates (VH2O) of the gregarious caterpillar Eutricha capensis, by comparing individu...
Article
1. Terrestrial ectotherms are likely to face increased periods of heat stress as mean temperatures and temperature variability increase over the next few decades. Here, we consider the extent to which changes in upper thermal limits, through plasticity or evolution, might be constrained, and we survey insect and reptile data to identify groups like...
Article
Driven by the mobility of organisms and novel habitats created by anthropogenic changes of landscape structure and climate, range expansion can modify the functioning of recipient ecosystems by altering ecosystem processes such as intra-and cross-trophic biotic interactions. We explain the spatial and temporal dynamics of the recent range expansion...
Article
Full-text available
Velvet worms (Onychophora) are characterised by a dearth of mechanisms to retain water, yet recently identified cryptic species are located in areas with seemingly different climates. Using flow-through respirometry, this study determined the metabolic, water loss and cuticular water loss rates of two cryptic species of Opisthopatus cinctipes s.l....
Data
Online Resource 1. Standard metabolic rate of Opisthopatus cinctipes s.l. from two sites in the Eastern Cape, South Africa, at three test temperatures. A: 15 °C; B: 10 °C; C: 5 °C. Black diamonds: Katberg; grey circles: Zuurberg.
Data
Online Resource 2. Cuticular water loss rate of Opisthopatus cinctipes s.l. from two sites in the Eastern Cape, South Africa, at three test temperatures. A: 15 °C; B: 10 °C; C: 5 °C. Black diamonds: Katberg; grey circles: Zuurberg
Article
Critical thermal limits provide an indication of the range of temperatures across which organisms may survive, and the extent of the lability of these limits offers insights into the likely impacts of changing thermal environments on such survival. However, investigations of these limits may be affected by the circumstances under which trials are u...
Article
Determining organismal responses to climate change is one of biology's greatest challenges. Recent forecasts for future climates emphasize altered temperature variation and precipitation, but most studies of animals have largely focused on forecasting the outcome of changes in mean temperature. Theory suggests that extreme thermal variation and pre...
Article
Full-text available
Using a regionally calibrated model, Sinervo et al. (Reports, 14 May 2010, p. 894) predicted potential climate change impacts on lizard populations and estimated that many extinctions are under way. We argue that this model is not sufficient for predicting global losses in lizard species in response to anthropogenic climate change.
Article
An official journal of the Genetics Society, Heredity publishes high-quality articles describing original research and theoretical insights in all areas of genetics. Research papers are complimented by News & Commentary articles and reviews, keeping researchers and students abreast of hot topics in the field.
Article
Investigation of gas exchange patterns and modulation of metabolism provide insight into metabolic control systems and evolution in diverse terrestrial environments. Variation in metabolic rate in response to environmental conditions has been explained largely in the context of two contrasting hypotheses, namely metabolic depression in response to...
Article
Full-text available
Temperature dependence, energetics, and speed of locomotion have important implications for the ecology and evolution of ants. Here, we report the results of a full-factorial study investigating the responses of active metabolic rate (AMR), voluntary locomotion speed, and cost of transport (COT) to three temperature acclimations (7-10 d; 20 degrees...