Pieter A ArnoldAustralian National University | ANU · Research School of Biology (RSB)
Pieter A Arnold
BSc (Hons), PhD
About
34
Publications
8,014
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Introduction
My research is focused on the ecology and evolution of organisms and functional or ecophysiological responses to environmental change. My research investigates phenotypic plasticity and thermal tolerance in plants in response to the changing climate - mainly heat and drought stress. My interests are broad and I am also involved in projects covering evidence synthesis (systematic reviews and meta-analyses), dispersal, metabolic rate, host-pathogen interactions, and other stress responses.
Additional affiliations
March 2014 - December 2016
Position
- Tutor
Description
- Biostatistics & experimental design (2014-2016); Sampling design & analysis in conservation science (2014-2016); Evolutionary perspectives on modern society (2015-2016); Animal Behaviour (2016)
February 2013 - August 2016
Position
- PhD Student
Description
- I used an invasive beetle species to examine physiological and behavioural trait dynamics and movement patterns of individuals in response to selection pressure for high and low dispersal propensity.
February 2012 - December 2012
Position
- Honours Student
Description
- I investigated the physiological, metabolic, and behavioural consequences of viral infection on Drosophila melanogaster.
Education
February 2013 - January 2017
February 2009 - November 2012
Publications
Publications (34)
Climate change presents many challenges for plants, a major one of which is the steady increase in the temperatures that plants are exposed to during germination, growth, and reproduction. Generating a more complete understanding of the capacity for plants to respond and of the role that phenotypic plasticity plays in facilitating species’ response...
Seasonal snow is among the most important factors governing the ecology of many terrestrial ecosystems, but rising global temperatures are changing snow regimes and driving widespread declines in the depth and duration of snow cover. Loss of the insulating snow layer will fundamentally change the environment. Understanding how individuals, populati...
Plant biology is experiencing a renewed interest in the mechanistic underpinnings and evolution of phenotypic plasticity that calls for a re‐evaluation of how we analyse phenotypic responses to a rapidly changing climate. We suggest that dissecting plant plasticity in response to warming temperature needs an approach that (1) can represent plastici...
Understanding plant thermal tolerance is fundamental to predicting impacts of extreme temperature events that are increasing in frequency and intensity across the globe. Extremes, not averages, drive species evolution, determine survival, and increased crop performance. To better prioritise agricultural and natural system research, it is crucial to...
![Differences in a the inter-group initial trait difference [(C – A)/A]...](publication/358421930/figure/fig3/AS:1137707975753730@1648262127835/Differences-in-a-the-inter-group-initial-trait-difference-C-A-A-and-b-the-reaction_Q320.jpg)
Phenotypic plasticity index (PI), the slope of reaction norm (K) and relative distances plasticity index (RDPI), the most commonly used estimators, have occasionally been found to generate different plasticity rankings between groups (species, populations, cultivars or genotypes). However, no effort has been made to determine how frequent this inco...
Snow is an important driver of ecosystem processes in cold biomes. Snow accumulation determines ground temperature, light conditions, and moisture availability during winter. It also affects the growing season’s start and end, and plant access to moisture and nutrients. Here, we review the current knowledge of the snow cover’s role for vegetation,...
Snow is an important driver of ecosystem processes in cold biomes. Snow accumulation determines ground temperature, light conditions and moisture availability during winter. It also affects the growing season’s start and end, and plant access to moisture and nutrients. Here, we review the current knowledge of the snow cover’s role for vegetation, p...
High phenotypic plasticity has long been considered as a characteristic promoting exotic plant invasions. However, the results of the studies testing this hypothesis are still inconsistent. Overlooking the effects of species resource requirements and environmental resource availability may be the main reasons for the ambiguous conclusions. Here, we...
Explaining variation in the fitness of organisms is a fundamental goal in evolutionary ecology. Maintenance energy metabolism is the minimum energy required to sustain biological processes at rest (resting metabolic rate: RMR) and is proposed to drive or constrain fitness of animals; however, this remains debated. Hypotheses have been proposed as t...
When seeking to inform and improve prevention efforts and policy, it is important to be able to robustly synthesize all available evidence. But evidence sources are often large and heterogeneous, so understanding what works, for whom, and in what contexts can only be achieved through a systematic and comprehensive synthesis of evidence. Many barrie...
Global warming may pose a serious threat to seed germination and establishment in alpine ecosystems, given that temperature is a primary factor in stimulating seed germination and regulating changes in seed dormancy. However, to date, little is known about the relative importance of temperatures experienced by parents versus by the seeds (after dis...
Plant thermal tolerance is a crucial research area as the climate warms and extreme weather events become more frequent. Leaves exposed to temperature extremes have inhibited photosynthesis and will accumulate damage to PSII if tolerance thresholds are exceeded. Temperature-dependent changes in basal chlorophyll fluorescence (T-F0) can be used to i...
Climate change is generating both sustained trends in average temperatures and higher frequency and intensity of extreme events. This poses a serious threat to biodiversity, especially in vulnerable environments, like alpine systems. Phenotypic plasticity is considered to be an adaptive mechanism to cope with climate change in situ, yet studies of...
Synthesis of evidence from the totality of relevant research is essential to inform and improve prevention efforts and policy. Given the large and usually heterogeneous evidence available,reaching a thorough understanding of what works, for whom, and in what contexts, can only be achieved through a systematic and comprehensive synthesis of evidence...
Plant thermal tolerance is a crucial research area as the climate warms and extreme weather events become more frequent. We developed and tested a high-throughput method for measuring photosynthetic critical thermal limits at low ( CT MIN ) and high ( CT MAX ) temperatures to achieve pragmatic and robust measures of thermal tolerance limits using a...
Seasonal snow is among the most important factors governing the ecology of many terrestrial ecosystems, but rising global temperatures are changing snow regimes and driving widespread declines in the depth and duration of snow cover. Loss of the insulating snow layer will fundamentally change the environment – far more than incremental temperature...
Current policy has the world on track to experience around 3°C of warming by 2100. The responses of organisms to our warming world will be mediated by changes in physiological processes, including metabolic rate. Metabolic rate represents the energetic cost of living, and is fundamental to understanding the energy required to sustain populations. C...
Synthesizing evidence is an essential part of scientifc progress, but it is often done in a slow and uncoordinated
manner, sometimes producing misleading conclusions. Here, we propose the idea of an ‘open synthesis
community’ to resolve this pressing issue.
An understanding of how sublethal exposure to phosphine affects an organism’s respiration is important for predicting its effects on activities depending on a reliable energy source including movement. After treatment with the appropriate sublethal doses of phosphine (LC10), both resistant and susceptible Tribolium castaneum beetles suffered reduct...
Plants tolerate temperature extremes within physiological limits before they can no longer photosynthesise and begin to incur damage. We can measure the critical thermal limits of leaves using many different methods. But how do variations within a measurement method affect estimates of thermal tolerance limits? Can we make valid interspecific compa...
Organisms vary widely in size, from microbes weighing 0.1 pg to trees weighing thousands of megagrams — a 1021-fold range similar to the difference in mass between an elephant and the Earth. Mass has a pervasive influence on biological processes, but the effect is usually non-proportional; for example, a tenfold increase in mass is typically accomp...
Phenotypic plasticity is frequently assumed to be an adaptive mechanism by which organisms cope with rapid changes in their environment, such as shifts in temperature regimes owing to climate change. However, despite this adaptive assumption, the nature of selection on plasticity within populations is still poorly documented. Here, we performed a s...
1. Temperature plays a fundamental role in the dynamics of host–pathogen interactions. Wolbachia is an endosymbiotic bacteria that infects about 40% of arthropod species, which can affect host behaviour and reproduction. Yet, the effect of Wolbachia on host thermoregulatory behaviour is largely unknown, despite its use in disease vector control pro...
Temperature plays a fundamental role in the dynamics of host-pathogen interactions.
Wolbachia is an endosymbiotic bacteria that infects about 40% of arthropod species, which can affect host behaviour and reproduction. Yet, the effect of Wolbachia on host thermoregulatory behaviour is largely unknown, despite its use in disease vector control progra...
Individuals vary in their ability to disperse. Much of this variation can be described by covarying phenotypic traits that are related to dispersal (constituting the 'dispersal phenotype' or 'dispersal syndrome'), but the nature of the associations among these traits are not well understood. Unravelling the associations among traits that potentiall...
The natural dispersal of Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) has been emulated in the laboratory for more than 50 years, using a simple dispersal apparatus. This has typically comprised of a starting container (initial resource or patch) connected by tubing, which contains thread for the animals to climb into a tube and hence to...
The cerambycid beetles comprise a diverse family that includes many economically important pests of living and dead trees. Pheromone lures have been developed for cerambycids in many parts of the world, but to date, have not been tested in Australia. In this study, we tested the efficacy of several pheromones, identified from North American and Eur...
Transitioning between life stages involves significant changes to the physiology, structural morphology, biochemistry and behaviour of an organism. Eclosion, metamorphosis and the onset of sexual maturity have consequences for the life history evolution of an organism by initiating reproductive and dispersal-related behaviours that are both energet...
Understanding viral dynamics in arthropods is of great importance when designing models to describe how viral spread can influence
arthropod populations. The endosymbiotic bacterium Wolbachia spp., which is present in up to 40% of all insect species, has the ability to alter viral dynamics in both Drosophila spp. and mosquitoes, a feature that in m...
Behavioural fever is a widely conserved response to infection. The host increases body temperature (Tb) by altering their preferred temperature (Tp), generating a fever and delaying or avoiding pathogen-induced mortality. This response is not ubiquitous in insects, however, though few studies have investigated this response to viral infection. Here...
An extensively used model system for investigating anti-pathogen defence and innate immunity involves Drosophila C virus (DCV) and Drosophila melanogaster. While there has been a significant effort to understand infection consequences at molecular and genetic levels, an understanding of fundamental higher-level physiology of this system is lacking....
Projects
Projects (2)
Individual differences in dispersal contribute to the evolution of traits at population range edges during biological invasions. This project aimed to determine the influence of age on dispersal-related traits (e.g., body size, limb length, metabolic rate, and movement characteristics), the relationships among these traits, and how they evolve under experimental spatial assortment. To meet these aims we are using a model species, the red flour beetle (Tribolium castaneum) in a laboratory dispersal system.
The Drosophila melanogaster – Drosophila C virus (DCV) model system is widely used, however an understanding of fundamental higher-level physiology of this host-virus system has been largely unexplored. The aim of this project was to investigate the consequences of viral infection at the whole-animal level, specifically exploring metabolic rate, mass, water content, spontaneous activity, and temperature preference of infected and non-infected flies across the infection period leading to mortality.
