S.J. Simpson's research while affiliated with The University of Sydney and other places

Publications (87)

Article
Nutritional environments, particularly those experienced during early life, are hypothesized to affect longevity. A recent cross-Taxa meta-Analysis found that, depending upon circumstance, average longevitymay be increased or decreased by early-life dietary restriction. Unstudied are the effects of diet during development on among-individual varian...
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Nutrition has long been considered more the domain of medicine and agriculture than of the biological sciences, yet it touches and shapes all aspects of the natural world. The need for nutrients determines whether wild animals thrive, how populations evolve and decline, and how ecological communities are structured.The Nature of Nutritionis the fir...
Chapter
David Raubenheimer was born and grew up in Cape Town, South Africa. He completed his B.Sc. and M.Sc. at the University of Cape Town, before moving to Oxford in 1987 to do a Ph.D. on insect nutrition. In 1991, David returned to Cape Town to take up a 1-year Postdoctoral Fellowship, and in 1992 returned to Oxford to take up a position as departmental...
Article
Excessive weight gain appears, thermodynamically at least, straightforward: growing energy intake and/or falling energy expenditure create an energetic surplus, resulting in fat accumulation. The situation is, however, far more complex, with genetic, physiological, social, psychological and economic factors all implicated. Thus the causes of excess...
Article
1In insects, cuticular melanization and immune function are strongly dependent on the quantity of dietary protein ingested. However, relatively little is known about the role played by the quality of nitrogenous resources in determining phenotypic variation in the degree of melanization and correlated immunological functions. We explored this issue...
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To investigate the ability of insects to discriminate between nutritionally balanced and unbalanced foods, fifth-instar nymphs of Locusta migratoria L. (Orthoptera: Acrididae) were given one of thirteen pairings of artificial foods differing only in their concentration of protein and carbohydrate. One food, containing a previously estimated optimum...
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ABSTRACT Final instar nymphs of Locusta migratoria (L.) and larvae of Spodoptera littoralis (Boisduval) were given an artificial diet deficient in either protein or digestible carbohydrate for a single meal during ad libitum feeding, after which they were provided with a choice of two diets, one containing protein but no digestible carbohydrate and...
Article
The time-course of behavioural phase change was investigated in nymphs of Schistocerca gregaria, using logistic regression analysis of behaviour recorded in a standard assay. Gregarization occurred very rapidly. Solitary-reared nymphs became markedly gregarious in behaviour within 1-4h of being placed in a crowd. These insects re-solitarized equall...
Article
A recently developed framework was applied to investigate the responses of newborn pea aphids, Acyrthosiphon pisum (Harris) (Homoptera: Aphididae), to simultaneous variations in dietary suerose and amino acid levels. The location of functional ‘targets’ for intake and growth were determined experimentally using performance criteria. Behavioural rul...
Article
Final instar nymphs of the oligophagous acridid Locusta migratoria (L.) and larvae of the polyphagous noctuid Spodoptera littoralis (Boisduval) were fed for 4, 8 or 12 h, the conditioning period, on one of four artificial diets. Of these, diet PC contained 20% protein and 10% digestible carbohydrate; another, P, contained 20% protein but with the d...
Article
In social insects, decisions are usually predicted to be more accurate than individual decisions, because individual preferences are amplified at the group level. Although social caterpillars, as individuals, possess considerable ‘nutritional wisdom’ and have the capacity to regulate their nutrient intake: does this mean that the collective nutriti...
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Full-text available
Recent models from theoretical physics have predicted that mass-migrating animal groups may share group-level properties, irrespective of the type of animals in the group. One key prediction is that as the density of animals in the group increases, a rapid transition occurs from disordered movement of individuals within the group to highly aligned...
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Mounting effective resistance against pathogens is costly in terms of energy and nutrients. However, it remains unexplored whether hosts can offset such costs by adjusting their dietary intake so as to recoup the specific resources involved. We test this possibility by experimentally challenging caterpillars (Spodoptera littoralis) with a highly vi...
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Foraging deficiencies and supplementary feeding play critical roles in kakapo (Strigops habroptilus) breeding biology and conservation. We present a framework for the analysis of complex nutritional data (called the geometric framework - GF) which may contribute further understanding of the relationships between natural foods, supplementary feeding...
Article
It has been known for over a century that the dose-response curve for many micronutrients is non-monotonic, having an initial stage of increasing benefits with increased intake, followed by increasing costs as excesses become toxic. This phenomenon, termed Bertrand's rule, is widely assumed not to apply to caloric macronutrients. To date this assum...
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The obesity epidemic is among the greatest public health challenges facing the modern world. Regarding dietary causes, most emphasis has been on changing patterns of fat and carbohydrate consumption. In contrast, the role of protein has largely been ignored, because (i) it typically comprises only approximately 15% of dietary energy, and (ii) prote...
Article
We have studied the influence of variations in dietary protein (P) and digestible carbohydrate (C), the quantity of food eaten, and insect age during the fifth instar on the expression of the proliferating cell nuclear antigen (PCNA) in the epithelial cells of the midgut (with special reference to the midgut caeca) in the African migratory locust,...
Article
We examined correlates of nutrient balancing with dietary range by comparing diet selection and ingestive, post-ingestive and performance-related responses to macronutrient imbalance in two species of grasshopper. One of the two species, Locusta migratoria (the African migratory locust), is a specialist grass-feeder, while the other, Schistocerca g...
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Phase characteristics of locusts from parents that experienced different population densities were investigated under field conditions in Morocco. The density experienced by adults induced a marked phase change in colour, behaviour and morphometry of their offspring. A high-density subpopulation gave rise to a preponderance of black hatchlings that...
Article
[His(7)]-corazonin is a neuropeptide produced in the pars lateralis of the brain. It is stored in the corpora cardiaca and probably released from there. The only well-documented effect in locusts is increased melanization of the cuticle. We investigated whether this hormone might also be causally related to changes in behavior and morphometrics tha...
Article
The albino Okinawa strain of Locusta migratoria is deficient in the neurohormone [His(7)]-corazonin. This peptide induces darkening of the cuticle, one of the typical features of gregarious locusts. As part of a broader study on the possible role of [His(7)]-corazonin in phase transition, we explored whether corazonin-deficiency might be associated...
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Full-text available
A study was undertaken to assess the impact of the strepsipteran endoparasite Stichotrema dallatorreanum Hofeneder on the performance of its host Segestidea novaeguineae (Brancsik), a tettigoniid pest of oil palm in Papua New Guinea. This involved analyses of morphology, gut contents, body composition and reproductive variables of field-collected a...
Article
Nutritional regulatory responses of the generalist caterpillar Spodoptera littoralis (Boisduval) were explored, in choice and no-choice experiments, using the Geometric Framework. In the choice experiment, newly moulted final instar larvae were provided with one of three protein-biased foods (PB-food: p35:c7, p28:c5.6 or p21:c4.2) and one of three...
Article
Nutritional regulatory responses were compared for the cryptic 'solitarious' and the conspicuously coloured, aggregating 'gregarious' phases of the desert locust Schistocerca gregaria. The desert locust has the genetic potential to exist in either phase, changing between them within a lifetime and epigenetically across generations. Our aim was to c...
Article
A good understanding of the capabilities of commercially reared fish species to regulate intake of specific macronutrients has potential economic, welfare and environmental benefits. We present a conceptual and experimental framework for studying macronutrient intake in fish. This ‘geometric’ approach addresses the multidimensional and interactive...
Article
Feeding patterns were recorded and analysed for adult female weevils, Exopthalmus jekelianus (White) (Coleoptera: Curculionidae), feeding on Central American mahogany, Cedrela odorata L., in the field in Costa Rica. The study forms part of an investigation into the relationship between feeding patterns and the fine-scale variation in leaf chemistry...
Article
High resolution 1H NMR spectroscopy provided a rapid and non-invasive means of establishing a multicomponent profile of the low molecular weight organic metabolites present in the haemolymph of crowd-reared and solitary-reared desert locusts. Assignments of the 1H NMR resonances detected in the one-dimensional (1D) spectra were supported by the com...
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Full-text available
Desert locusts (Schistocerca gregaria Forskål (Orthoptera: Acrididae)) change phase in response to population density. Solitarious insects avoid one another; when crowded, they shift to the gregarious phase and aggregate. Laboratory experiments and individual-based modelling have shown that small-scale resource distribution can affect locust phase...
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Full-text available
Desert locusts in the solitarious phase were repeatedly touched on various body regions to identify the site of mechanosensory input that elicits the transition to gregarious phase behavior. The phase state of individual insects was measured after a 4-h period of localized mechanical stimulation, by using a behavioral assay based on multiple logist...
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Full-text available
The behaviour of herbivorous insects is influenced by their nutritional state. Nutrition-induced behavioural changes are often interpreted as adaptive mechanisms for controlling nutrient intake; however, their influence on other life history traits has received far less attention. We investigated the effect of food quality and distribution on the b...
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Full-text available
Desert locusts (Schistocerca gregaria) change phase in response to population density: ‘solitarious’ insects avoid one another, but when crowded they shift to the gregarious phase and aggregate. This individual-level process is the basis for population-level responses that may ultimately include swarm formation. We have recently developed an indivi...
Article
We present and illustrate using data from insects an integrative approach to modelling animal nutrition. This framework enables the unification within simple geometrical models of several nutritionally relevant measures. These include: the optimal balance and amounts of nutrients required to be ingested and allocated to growth by an animal over a g...
Article
We have studied the influence of variations in dietary protein and digestible carbohydrate content, of insect age and of time during the feeding cycle on the endocrine cells of the ampullar region of the midgut in the African migratory locust Locusta migratoria L. Morphometric analysis of FMRFamide-like immunoreactivity was used as an indirect meas...
Article
To determine whether relative enrichments of 15N and 13C in locusts are influenced by diet, locust nymphs were raised from hatchlings to adults on either seedling wheat or maize. Maize provided less hexose sugars and protein per gram than did wheat. Maize also depends on the C4 form of photosynthesis, while wheat uses the C3 form; this difference i...
Article
We describe and extend a graphical approach to quantitative nutrition that focuses on the interplay between behavioural and physiological components of nutritional regulation. The site of integration is the nutrient transfer function, which is the function describing the time course of nutrient transfer between serially connected nutritional compar...
Article
Locust nymphs were raised from hatching to adult locusts on either seedling wheat (C3) or maize (C4), to determine whether relative enrichments/depletions of 15N and 13C within body tissues are influenced by diet. The maize contained less hexose sugars and protein per gram than wheat. The isotopic spacing between the food and the whole insect was f...
Article
To investigate the consequences of different patterns of switching between nutritionally complementary foods, nymphs of Locusta migratoria L. (Orthoptera: Acrididae) were forced to alternate between pairs of artificial foods differing only in their protein and carbohydrate content at one of several fixed intervals. Total food and nutrient intake ov...
Article
Cross-sectional structural features of carbon nanotubes have been investigated by high resolution electron microscopy (HREM). Carbon nanotube-bundles with 0.2–0.6 mm in diameter and 5–10 mm in length were produced by means of an arc-discharge method, which is suitable for preparing TEM cross-sectional samples of carbon nanotubes. Our HREM observati...
Article
A conceptual framework is introduced which has been derived from work on insects. The scheme is intended to integrate studies of diet selection, regulation of amounts eaten, nutrient utilization, body composition and animal performance. Aspects of framework are illustrated with published data on macronutrient selection in the rat. An animal is view...
Article
Abstract Locust nymphs were raised from hatching to adult locusts on either seedling wheat (C(3)) or maize (C(4)), to determine whether relative enrichments/depletions of (15)N and (13)C within body tissues are influenced by diet. The maize contained less hexose sugars and protein per gram than wheat. The isotopic spacing between the food and the w...
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Full-text available
We present and apply to data for insects, chickens and rats a conceptual and experimental framework for studying nutrition as a multi-dimensional phenomenon. The framework enables the unification within a single geometrical model of several nutritionally relevant measures, including: the optimal balance and amounts of nutrients required by an anima...
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Full-text available
Maintenance of carbohydrate balance via changes in CO2 output volume was investigated in locusts using a flow-through respirometer. The effect of an imbalance in the dietary protein to digestible carbohydrate ratio on expired CO2 levels was measured in locusts fed one of two synthetic diets [7% protein, 21% digestible carbohydrate (7:21) and 21% pr...
Article
The design features of gustatory systems are considered in relation to the need for insect herbivores (or indeed any animal) to regulate their nutrient intake. The gustatory system (defined to include both peripheral and central components) should ideally be designed to reflect: (a) the average nutritional requirements of the insect during its vari...
Article
Nutrition can be viewed as a process whereby an organism transfers nutrients from the environment to its utilisation sinks. Accordingly, the quantitative study of nutrition centres around two key variables: the rate of nutrient transfer [henceforth termed ‘power’, following Slansky & Feeny (1977)] and the efficiency with which acquired nutrient is...
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Full-text available
Aspects of pre- and post-ingestive compensation were investigated in locusts (Locusta migratoria) fed nutritionally unbalanced artificial diets containing 7% protein and 21% digestible carbohydrate (7:21) or 21% protein and 7% digestible carbohydrate (21:7). Feeding behaviour and haemolymph levels of amino acids and sugars were measured in locusts...
Article
This study addresses the short-term behavioural mechanisms that underlie nutrient balancing by a herbivorous insect. Fifth instar Locusta migratoria nymphs were given one of four pairings of artificial foods, with each food containing different levels of protein and carbohydrate. The foods were chosen such that the treatment groups would have to in...
Article
A practical guide is provided for the use of recently developed techniques for the analysis of feeding and post-ingestive processing in insects. We argue that a primary aim of studies in nutrition should be the experimental estimation of the positions of functional optima (the intake, nutrient and growth targets) in nutrient space. Next, rules of b...
Article
Growth, survivorship and food intake were measured for newborn pea aphids maintained on one of 25 chemically-defined diets varying in sucrose and amino acid content (200–1000 and 50–250 mM, respectively), with amino acids comprising 20:80 essential/non-essentials (e:n). Survivorship varied positively with dietary amino acid concentration, while dry...
Article
We present a formalised, yet flexible, scheme for classifying and symbolising the components of nutrient budgets. The scheme distinguishes hierarchically both among components of the ingesta and among the various sinks to which they are allocated. The primary terms in the budget are distinguished according to either methodological criteria (whether...
Chapter
Insects have evolved means of using an extraordinary variety of food sources, many of which are, to say the least, nutritionally unpromising. In addition to possessing an impressive array of mechanisms to deal with the physical, chemical, and other challenges posed by such foods, it has become evident in recent years that insects can also cope with...
Article
1. We recommend the use of bicoordinate plots, termed utilization plots, for the analysis of nutrient budgets. 2. Utilization plots explore the relationship between nutrient uptake (intake or absorption from the gut) and the various compartments to which ingested nutrients are allocated. 3. They provide more information, and are numerically less pr...
Article
Investigations were undertaken into the mechanisms controlling regulation of salt intake in fifth-instar nymphs of Locusta migratoria L. Initially, the pattern of feeding was recorded for 24 h in locusts fed a chemically-defined food either with or without salt. Differences were apparent from the first meal, with smaller meals being eaten more freq...
Article
The quantitative profile of amino acids egested by fifth-stadium Locusta migratoria fed artificial foods differing in protein and carbohydrate content was investigated. Locusts fed foods with high (21%) protein content and low (7%) carbohydrate content selectively egested a large amount of lysine compared with other amino acids, despite its presenc...
Article
We have presented and tested in experiments with insects a new framework which integrates functional, mechanistic, ontogenetic and comparative aspects of nutrition. The framework firstly identifies local optima (nutritional, intake and growth `targets') within a multi-dimensional nutritional space, where each functionally relevant nutrient forms a...
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Full-text available
Summary Post-ingestive responses to four different diets containing protein and digestible carbohydrate in balanced (7% protein, 7% digestible carbohydrate or 21% protein, 21% digestible carbohydrate) or unbalanced proportions (7% protein, 21% digestible carbohydrate or 21% protein, 7% digestible carbohydrate) were assessed in fifth stadium Locusta...
Article
A synthesis is presented for the control of nutrient intake in insects. The haemolymph plays a central role and provides a constantly updated summary of nutritional state. Various ways are discussed in which haemolymph parameters are directly and indirectly linked to the three key aspects of feeding behaviour: food location, food selection and inge...
Article
Fifth-instar nymphs of Locusta migratoria exhibited regulatory feeding for salt by defending an “intake target” for salt vs non-mineràl nutrients when challenged with a range of choices of artificial foods varying in salt content. When provided with no choice of food, however, nymphs did not regulate salt intake, due to the greater strength of regu...
Article
A framework is presented for the study of feeding behaviour in the context of the multiple nutrient requirements of animals. Each nutrient required is represented by a single axis in a multi-dimensional plot. At any time the tissues will require a particular quantity and mix of nutrients. This ideal point is termed the 'nutritional target'. Meeting...
Article
Fifth-instar caterpillars chew more or less continuously after their neck connectives have been cut, implying that the neural circuitry responsible for chewing is tonically inhibited by input arriving via the neck connectives. We have investigated the source of this inhibitory signal by lesion experiments. It appears to originate in peripheral stru...
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This study concerns the responses of the pea aphid Acyrthosiphon pisum to chemically-defined diets containing different concentrations of nitrogen (45–270 mM amino acids) and how these responses are influenced by the antibiotic chlortetracycline, which selectively disrupts the aphids' symbiotic bacteria. The chlortetracycline-treated aphids ingeste...
Article
Some statistical problems are added to the growing list of cautionary tales regarding the use of the conventional, ratio-based nutritional indices (RCR, RGR, ECI, AD and ECD). Analysis of ratios is based on the, probably unrealistic, assumption of an isometric relationship between denominator and numerator variables. Analysis of covariance (ANCOVA)...
Chapter
Meeting the nutritional needs of an insect can be seen as a problem of multidimensional geometry. At any given time there is a requirement by the tissues for a particular quantity and mix of nutrients. This constitutes a “nutritional target” in an n-dimensional s’ a’ e, where n is the number of nutrients. Providing the tissues with nutrients involv...
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Full-text available
Summary 1. This paper forms part of our study of the behavioural and neural mechanisms involved in dietary selection behaviour of larvae of the polyphagous noctuid Spodoptera littoralis (Boisduval). 2. Larvae were conditioned on one of four chemically defined artificial diets for 4, 8 or 12 h. Diets differed in their proportions of protein and dige...
Article
Investigations into the behavioural and underlying physiological mechanisms of dietary selection are presented for the locust, Locusta migratoria. Locusts were fed for 4, 8 or 12 h on one of four chemically defined artificial diets: diet PC, which was nutritionally complete; diet P, containing no digestible carbohydrate; diet C, containing no prote...
Article
Experiments are described that show, first, that locusts, Locusta migratoria (L.), are able to associate an odour paired with a diet and the protein content of that diet and, second, that the behavioural response shown to the odour depends specifically on the insects' state of protein deprivation. Nymphs were trained for 2 days with free access to...
Article
Dietary selection was investigated during the first 15 days of adult life in male and female Locusta migratoria L. Insects were provided with two artificial diets, one containing 10, 20 or 28% protein but no digestible carbohydrate, the other 10, 20 or 28% digestible carbohydrate but no protein. Amounts eaten, detailed feeding patterns and somatic...
Article
There were no interactive effects of nutrient levels and tannic acid, despite the fact that both species compensated for dilution of dietary protein by increasing consumption. Only male Locusta compensated for dilution of dietary carbohydrates; this compensation was much less marked than for protein. Tannic acid did influence feeding as a main effe...
Article
The relationship between the amount eaten during a meal, meal duration and ingestion rate was investigated in the locust, Locusta migratoria (L.). The results suggested a relatively simple model for the control of meal termination whereby a variety of exogenous and endogenous factors, including chemosensory stimuli provided by the food, the presenc...
Article
SUMMARY 1. Previous work has shown that fifth-instar nymphs of Locusta migratoria (L.) compensate for a dilution of their dietary protein by reducing intermeat interval (Simpson & Abisgold, 1985). 2. The effect of dietary protein on intermeal interval is regulated, either directly or indirectly, by the osmolality and free amino acid content of the...
Article
SUMMARY 1. Previous work has demonstrated that fifth-instar nymphs of Locusta migrat- oria L. respond to differences in levels of dietary protein by altering intermeal interval but not meal size (Simpson & Abisgold, 1985): insects fed a diet with 14% protein (p) eat the same sized meals more frequently than those fed a diet with 28% protein (P). Th...
Article
The detailed behavioural mechanisms underlying an instance of compensation for changes in dietary nutrients are described for the first time in an insect. Nymphs of Locusta migratoria L. were given one of four artificial diets on the third day of the fifth instar, and their feeding patterns recorded in detail for 12 h. The diets represented combina...
Article
The role and nature of volumetric feedbacks in the regulation of meal size was investigated for Schistocerca gregaria. Feedback from the anterior region of the crop was found to be important and denervation led to hyperphagia. Additional feedbacks were found from more posterior gut regions. Cannulating agar or paraffin into the mid- and hindgut cau...
Article
The regulation of feeding in two insect groups, the locusts and the blowflies, is reviewed. The patterning of feeding is discussed first, and then the underlying mechanisms are considered in detail. The concept of "central excitability" is the key to understanding the controls of feeding. It represents a central nervous mechanism for tuning the sen...
Article
In the field in India, most eggs of Chilo partellus (Swinh.) hatched in the morning soon after first light. Laboratory experiments show that in continuous light hatching occurs after 250 hour-degrees of development above 12°C from the time at which the head capsule darkens (blackheading). Hatching may be advanced by a lights-on stimulus or retarded...
Chapter
The regulation of food intake has been investigated in a number of insects, most notably blowflies and locusts. Results have tended to suggest that the mechanisms involved vary considerably between groups, between species within groups, and even within a species under different conditions. This chapter provides an overall synthesis of feeding in th...
Article
Cavariella aegopodii is induced to land on traps by the monoterpene carvone, and the relevance of this to host-finding by the aphid is discussed. Catches are reduced by linalool. The interaction of plant chemicals in natural communities is discussed, and the possibility of using repellent chemicals for crop protection is suggested.

Citations

... However, meta-analysis of differences in variance should give increased power to detect effect modification. A small number of meta-analyses in epidemiology and ecology have reported on differences in variance, 9,10,[15][16][17][18][19][20][21][22][23] with applications to RCTs and other types of comparative study. Most of them found evidence of a difference in variance between arms, with varying strength of evidence (eTable 1; http://links.lww.com/EDE/B835). ...
... The temperature tolerance range in which locusts are active is 18 -45 °C (Herter, 1953) and the mean of temperature preference is around 29 °C (Herter, 1953), but can reach values up to 35 °C (Makings, 1987). The preferred temperature range is plastic and depends on body size, developmental stage and is conjunct to nutrition absorption (Chapman, 1955;Clark, 2014;Herter, 1953) or pathogen infection (Ouedraogo et al., 2003;Zimmer, 2001). ...
... This further emphasises the significance of our findings. Future research is advised to investigate the impact of nutritional supplementation on habitual protein intake in older populations since according to the Protein Leverage Hypothesis dietary protein is more tightly regulated (Simpson et al. 2005;Martinez-Cordero et al. 2012). ...
... The nutrient content of animals, measured through elements or macronutrients, underpins many biological processes, and each nutrient performs a distinct set of roles, from energy provision to cell signalling (Elser & Sterner, 2002;Roeder & Behmer, 2014;Simpson & Raubenheimer, 2012). Nutrition has long been associated with ecology and integrated into studies of ecological interactions (Lihoreau et al., 2015;Simpson, Raubenheimer, Charleston, & Clissold, 2010) from dietary choice by individual foragers to flows of elements through entire ecosystems (Elser & Sterner, 2002;Raubenheimer et al., 2009;Simpson & Raubenheimer, 2012). These studies have often focused on specific taxa or contexts, such as nutrient-based prey choice in spiders (Rendonet al. 2019), balancing of macronutrient intake by mink (Mayntzet al. 2009), compensatory feeding in beetles following diapause (Raubenheimer, Mayntz, Simpson, & Toft, 2007), nutrient recycling by zooplankton and fish (Elser & Urabe, 1999) or trophic cascades in lakes (Elser, Chrzanowski, Sterner, & Mills, 1998). ...
... Supplemental food can cause concentrations of animals at the feeding sites, which increases intraspecific and interspecific contact and thus infectious disease risks (Lawson et al., 2012;Adelman et al., 2015;Wilcoxen et al., 2015;Murray et al., 2016). Supplemental food with insufficient nutritional quality might result in malnutrition and harm the physiology and health of the conservation targets (Ishigame et al., 2006;Raubenheimer and Simpson, 2006). Supplemental feeding can affect offspring sex ratio and increase the risks of stochastic fluctuations in the sex ratio in small populations (Clout et al., 2002). ...
... Because neither food intersects the intake target, in this case the regulatory challenge is more complex: it needs to 'zig-zag' its way to the target by combining a series of steps none of which on its own would be adequate. To achieve this, regulatory systems are needed that are linked independently to the two nutrients, enabling the animal to switch to the high-protein food with carbohydrate-replete and protein-deficient, and vice versa, and terminate feeding only when the target levels for both nutrients are achieved simultaneously (26) . ...
... The consumption of protein and essential amino acids is tightly controlled in animals. Previous studies revealed that forced feeding of animals with a low-protein diet increases total calorie intake, because of compensatory feeding for essential amino acid intake [56]. In contrast, rodents reject diets that lack even a single essential amino acid [57]. ...
... Finally, it is possible that the bees needed to consume more pollen substitute than natural pollen to fulfill their nutritional needs, giving the appearance of "preference" for the substitute diet when it is just a need to consume more to receive the same level of nutrition as they would if they consumed bee bread. Some insects are known to overeat to compensate for insufficient nutrients (Simpson et al., 1995). For example, Haydak (1949) found that honey bees ingested more total nitrogen than usual when pollen substitutes were deficient in certain vitamins. ...
... Animals often balance their diet to maximize life-history traits with diverging nutritional needs (Raubenheimer & Simpson, 2020;Simpson & Raubenheimer, 2012). This creates the potential for trade-offs in the balance and allocation of nutrients needed for optimum fitness, aka "nutritional trade-off" (Lee et al., 2008;Maklakov et al., 2008;Morimoto & Lihoreau, 2019). ...
... So the foraging on different resources at the same time is the best strategy adapted by social insects like bees to get a balanced diet (McLellan, 1978). Insects can detect the level of amino acid and could reject the diet that is deficient amino acids (Abisgold and Simpson, 1987;Simpson et al., 1990;Ribeiro and Dickson, 2010;Toshima and Tanimura, 2012). The balance of nutrients is a complex phenomenon in which alimentary cues are integrated with the prerecorded information about food quality (Simpson and Raubenheimer, 2012b). ...