Sara Diana Leonhardt

Sara Diana Leonhardt
Technische Universität München | TUM · Department of Ecology and Ecosystem Management

32.49
 · 
Dr. rer. nat.

About

105
Publications
17,296
Reads
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Citations
Introduction
No living being survives without food and shelter. The struggle for resource acquisition has thus shaped most biotic interactions. Plant-insect interactions, both antagonistic and mutualistic ones, frequently (if not always) involve resource allocation, shaping the ecology and life history traits of plants and insects alike. I am interested in the mechanisms by which insects exploit resources and how resources influence their (chemical) ecology, fitness and diversity.
Research Experience
August 2013 - present
University of Wuerzburg
Position
  • Akademische Rätin
March 2011 - July 2013
Leuphana University Lüneburg
Position
  • postdoctoral researcher
August 2005 - July 2006
Duke University
Position
  • Visiting student

Publications

Publications (105)
Article
Full-text available
Dietary macro-nutrients (i.e., carbohydrates, protein, and fat) are important for bee larval development and, thus, colony health and fitness. To which extent different diets (varying in macro-nutrient composition) affect adult bees and whether they can thrive on nectar as the sole amino acid source has, however, been little investigated. We invest...
Article
Full-text available
Bees need food of appropriate nutritional quality to maintain their metabolic functions. They largely obtain all required nutrients from floral resources, i.e., pollen and nectar. However, the diversity, composition and nutritional quality of floral resources varies with the surrounding environment and can be strongly altered in human-impacted habi...
Article
Full-text available
Nectar is crucial to maintain plant-pollinator mutualism. Nectar quality (nutritional composition) can vary strongly between individuals of the same plant species. The factors driving such inter-individual variation have however not been investigated closer. We investigated nectar quality of field scabious, Knautia arvensis in different grassland p...
Article
Full-text available
Preventing malnutrition through consuming nutritionally appropriate resources represents a challenge for foraging animals. This is due to often high variation in the nutritional quality of available resources. Foragers consequently need to evaluate different food sources. However, even the same food source can provide a plethora of nutritional and...
Article
Full-text available
Land-use change and habitat loss have profoundly disturbed the resource availability for many organisms in farmlands, including bees. To counteract the resulting decline of bees and to maintain their pollination service to crops, bee pollinator-friendly schemes have been developed. We assessed the most established bee pollinator-friendly schemes wh...
Presentation
Several studies have highlighted the importance of natural habitat to support bees in disturbed landscapes such as agroecosystems. However, little is known about the specific habitat requirements of solitary bees in such landscapes. We aimed to identify the plant sources of nest materials and brood provisions for cavity-nesting solitary bees in nat...
Article
Full-text available
A prime example of plant–animal interactions is the interaction between plants and pollinators, which typically receive nectar and/or pollen as reward for their pollination service. While nectar provides mostly carbohydrates, pollen represents the main source of protein and lipids for many pollinators. However, the main function of pollen is to car...
Article
Stingless bees are highly social pollinators in tropical ecosystems. Besides floral pollen and nectar, they collect substantial amounts of plant resins, which are used for nest construction/maintenance and defence against antagonists. Moreover, some stingless bees extract chemical compounds from resins and incorporate them in their cuticular chemic...
Article
Full-text available
Sand mines represent anthropogenically impacted habitats found worldwide, which bear potential for bee conservation. Although floral resources can be limited at these habitats, vegetation free patches of open sandy soils and embankments may offer good nesting possibilities for sand restricted and other bees. We compared bee communities as found in...
Article
Full-text available
Like all animals, bees need to consume essential amino acids to maintain their body’s protein synthesis. Perception and discrimination of amino acids are, however, still poorly understood in bees (and insects in general). We used chemotactile conditioning of the proboscis extension response (PER) to examine (1) whether Bombus terrestris workers are...
Article
Full-text available
Honeybees (Apis mellifera) are threatened by numerous pathogens and parasites. To prevent infections they apply cooperative behavioral defenses, such as allo-grooming and hygiene, or they use antimicrobial plant resin. Resin is a chemically complex and highly variable mixture of many bioactive compounds. Bees collect the sticky material from differ...
Data
List of all substances identified from resin samples of trees, bees and propolis and their relative amounts. (XLSX)
Data
List of substance classes and number components identified from resin samples. (DOCX)
Article
Full-text available
Bee population declines are often linked to human impacts, especially habitat and biodiversity loss, but empirical evidence is lacking. To clarify the link between biodiversity loss and bee decline, we examined how floral diversity affects (reproductive) fitness and population growth of a social stingless bee. For the first time, we related availab...
Article
Full-text available
Bees receive nectar and pollen as reward for pollinating plants. Pollen of different plant species varies widely in nutritional composition. In order to select pollen of appropriate nutritional quality, bees would benefit if they could distinguish different pollen types. Whether they rely on visual, olfactory and/or chemotactile cues to distinguish...
Data
Percentage of proboscis extension responses (%PER) shown by Apis mellifera individuals (N = 39) in differential olfactory conditioning to the odor of apple versus almond pollen over 10 trials with separate lines for rewarded (S+, filled symbols) and unrewarded (S-, clear symbols) stimuli. Both, apple (grey) and almond (black) pollen were used as S+...
Data
Number of individuals showing a proboscis extension response (PER) (dark grey) and not showing a PER (light grey) in the first trial of all experiments performed. There were no significant differences (n.s.) between different seasons or light conditions (Chi22 = 0.82, P = 0.663). (TIF)
Data
Number of proboscis extension responses (PER) shown by Apis mellifera individuals (N = 132) in differential chemotactile conditioning of summer (N = 64, left) and winter (N = 64, right) bees to the taste of apple versus almond pollen. Boxplots display responses to S+ and S-. S+ represents the rewarded stimulus, S- the unrewarded stimulus. Both, app...
Data
Amino acid content (in μmol/g dry weight) of apple and almond pollen used in the PER experiments: determined via ion exchange chromatography (see [27]). In addition to concentrations of 20 protein-coding amino acids, concentrations for gamma-Aminobutyric acid (GABA) and hydroxyproline are provided. (DOCX)
Data
Percentage of proboscis extension responses (%PER) shown by Apis mellifera individuals (N = 64) in differential chemotactile conditioning in the dark to the taste of apple versus almond pollen over 10 trials with all stimuli separated. S+ (filled) represents the rewarded conditioned stimulus, S- (clear) the unrewarded conditioned stimulus. Both, ap...
Presentation
Full-text available
Alpine Bombus International Meeting 29th-31st July, 2018 Book of Abstracts
Data
Data on chemotactile and olfactory PER conditioning to test which stimuli honeybees use to differentiate between different pollen types
Presentation
Trap nests or “bee hotels” have been used to manage solitary bees since the 1950s in agriculture, research and, more recently, for urban conservation. Various designs are available for different purposes and target species, however, site characteristics such as land use also need to be considered. In this study, we test the performance of a hybrid...
Article
Full-text available
Plant performance is correlated with element concentrations in plant tissue, which may be impacted by adverse chemical soil conditions. Antibiotics of veterinary origin can adversely affect plant performance. They are released to agricultural fields via grazing animals or manure, taken up by plants and may be stored, transformed or sequestered by p...
Data
data set used to test for effect of habitat and surrounding plant species richness on various fitness parameters in the Australian stingless bee Tetragonula carbonaria
Article
Stingless bees (Hymenoptera, Apidae: Meliponini) represent a highly diverse group of social bees confined to the world's tropics and subtropics. They show a striking diversity of structural and behavioral adaptations and are important pollinators of tropical plants. Despite their diversity and functional importance, their ecology, and especially ch...
Article
Full-text available
Numerous studies revealed a positive relationship between biodiversity and ecosystem functioning, suggesting that biodiverse environments may not only enhance ecosystem processes, but also benefit individual ecosystem members by, for example, providing a higher diversity of resources. Whether and how the number of available resources affects resour...
Article
Antibiotics of veterinary origin are released to agricultural fields via grazing animals or manure. Possible effects on human health through the consumption of antibiotic exposed crop plants have been intensively investigated. However, information is still lacking on the effects of antibiotics on plants themselves, particularly on non-crop species,...
Article
Full-text available
Chemical communication is ubiquitous. The identification of conserved structural elements in visual and acoustic communication is well established, but comparable information on chemical communication displays (CCDs) is lacking. We assessed the phenotypic integration of CCDs in a meta-analysis to characterize patterns of covariation in CCDs and ide...
Article
Full-text available
When tasting food, animals rely on chemical and tactile cues, which determine the animal’s decision on whether or not to eat food. As food nutritional composition has enormous consequences for the survival of animals, food items should generally be tasted before they are eaten or collected for later consumption. Even though recent studies confirmed...
Article
Full-text available
Social immunity is a key factor for honeybee health, including behavioral defense strategies such as the collective use of antimicrobial plant resins (propolis). While laboratory data repeatedly show significant propolis effects, field data are scarce, especially at the colony level. Here, we investigated whether propolis, as naturally deposited in...
Article
Tree invasions have substantial impacts on biodiversity and ecosystem functioning, and trees that are dispersed by animals are more likely to become invasive. In addition, hybridisation between plants is well documented as a source of new weeds, as hybrids gain new characteristics that allow them to become invasive. Corymbia torelliana is an invasi...
Article
Full-text available
To date, no study has investigated how landscape structural (visual) alterations affect navigation and thus homing success in stingless bees. We addressed this question in the Australian stingless bee Tetragonula carbonaria by performing marking, release and re-capture experiments in landscapes differing in habitat homogeneity (i.e., the proportion...
Article
Access to abundant and diverse floral plant sources is essential for generalist bees as they obtain all energy and nutrients required from pollen and nectar. Despite their importance, we still know little about the precise nutritional requirements of most bee species. Here, we investigated differences in floral and amino acid profiles of pollen col...
Article
Full-text available
Context Abundance and diversity of bumblebees have been declining over the past decades. To successfully conserve bumblebee populations, we need to understand how landscape characteristics affect the quantity and quality of floral resources collected by colonies and subsequently colony performance. Objectives We therefore investigated how amount an...
Article
Full-text available
Nutritional deficits may be one factor contributing to the ongoing decline of wild and managed bees. As a consequence, interest in understanding the effect of floral resource availability on nutritional intake - and subsequently bee health and performance - has increased. However, the proximate mechanisms underlying bee foraging choices are still p...
Article
Full-text available
Insect life strategies comprise all levels of sociality from solitary to eusocial, in which individuals form persistent groups and divide labor. With increasing social complexity, the need to communicate a greater diversity of messages arose to coordinate division of labor, group cohesion, and concerted actions. Here we summarize the knowledge on p...
Article
Full-text available
Increasing human land use for agriculture and housing leads to the loss of natural habitat and to widespread declines in wild bees. Bee foraging dynamics and fitness depend on the availability of resources in the surrounding landscape, but how precisely landscape related resource differences affect bee foraging patterns remains unclear. To investig...
Data
Table S1. Location of study sites and geographic information. Data S1. Influence of daytime. Table S2. Spearman correlation matrix with correlation coefficients (rS) for forager numbers and weather variables. Table S3. Results of generalized linear mixed effect models (GLMMs) for each response variable, for the second year with all weather facto...
Article
Full-text available
Tree invasions have substantial impacts on biodiversity and ecosystem functioning, and trees that are dispersed by animals are more likely to become invasive. In addition, hybridisation between plants is well documented as a source of new weeds, as hybrids gain new characteristics that allow them to become invasive. Corymbia torelliana is an invasi...
Article
Full-text available
Body surfaces of organisms must prevent desiccation and inhibit the intrusion of harmful compounds and organisms. In insects, these functions are fulfilled by their cuticle, of which the external one represents a lipid layer that comprises different compound groups with various functions. In the highly social stingless bees, cuticular compounds are...
Conference Paper
Full-text available
Increasing human land use for farming and housing led to the loss of natural habitat and to widespread declines in wild bees, which in turn puts pollination services at risk. The quantity and quality of plant resources available in a landscape drive bee foraging dynamics and hence fitness of bee colonies. Yet how bee foraging patterns and colony pe...
Article
Full-text available
In view of the ongoing pollinator decline, the role of nutrition in bee health has received increasing attention. Bees obtain fat, carbohydrates and protein from pollen and nectar. As both excessive and deficient amounts of these macronutrients are detrimental, bees would benefit from assessing food quality to guarantee an optimal nutrient supply....
Article
Full-text available
Bumble bees play an important role as pollinators of many crop plants and wild flowers. As in many wild bees, their abundance and diversity have declined in recent years, which may threaten the stability of pollination services. The observed decline is often linked with the loss or alteration of natural habitat, e.g., through urbanization, the conv...
Article
Many insect groups are important mutualistic partners of plants. Bees in particular provide an essential mutualistic service to plants: pollination of their flowers. They can also act as seed dispersers for plants, a rare seed dispersal mutualism termed melittochory. One group of known bee seed dispersers are stingless bees (Apidae: Meliponini). Au...
Article
Full-text available
Recent evidence highlights the value of wild-insect species richness and abundance for crop pollination worldwide. Yet, deliberate physical importation of single species (eg European honey bees) into crop fields for pollination remains the mainstream management approach, and implementation of practices to enhance crop yield (production per area) th...
Conference Paper
Full-text available
Global declines in wild and native bees have raised concerns about reliable pollination services to crop plants. The bees in turn depend on the availability and diversity of their key resources (pollen, nectar, resin) provided by various plants. Yet how plant composition and resource diversity on the landscape level affect the foraging behaviour an...
Article
Full-text available
Biodiverse environments provide a variety of resources that can be exploited by consumers. While many studies revealed a positive correlation between biodiversity and consumer biomass and richness, only few studies have investigated how resource diversity affects single consumers. To better understand whether a single consumer species benefits from...
Article
Full-text available
Stingless bees accumulate deposits of plant resins that are mixed with beeswax to produce propolis. Previous studies have reported anti-microbial constituents of stingless bee (Tetragonula carbonaria) propolis from East Australia, but several components remained to be characterized. In the search of natural products yet unreported for Australian pr...
Article
Full-text available
Bacterial symbionts of insects have received increasing attention due to their prominent role in nutrient acquisition and defense. In social bees, symbiotic bacteria can maintain colony homeostasis and fitness, and the loss or alteration of the bacterial community may be associated with the ongoing bee decline observed worldwide. However, analyses...
Conference Paper
Background/Question/Methods In animal farming, veterinary anti-infectives such as antibiotics are frequently used. They are incompletely metabolized by the animals and excreted with manure. Through the use of manure as fertilizer, crop species can be exposed to these antibiotics when they persist in manure and soil but little is known about the e...
Conference Paper
Full-text available
Global declines of pollinators raise concerns about the stability of pollination services to wild and crop plants. Bees are highly important pollinators and strongly depend on (flowering) plants that provide their key resources (pollen, nectar, resin). How variations in landscape related resource diversity affect the foraging behaviour and colony f...
Article
Full-text available
Tetragonula carbonaria and Austroplebeia australis are two species of eusocial stingless bees with phylogeographically different origins that can occur sympatrically on the Australian east coast. We studied their foraging activity and resource intake and found pronounced differences between species. Tetragonula carbonaria showed consistently higher...
Article
Full-text available
Bees are in decline potentially leading to reduced pollination and hence production of insect-pollinated crops in many countries. It is however still unclear whether the consequences of pollinator shortages differ among countries with different environmental and societal conditions. Here, we calculated economic gains attributed to insect (particula...
Article
Full-text available
Chemical compounds are highly important in the ecology of animals. In social insects, compounds on the body surface represent a particularly interesting trait, because they comprise different compound classes that are involved in different functions, such as communication, recognition and protection, all of which can be differentially affected by e...
Conference Paper
Full-text available
Recent declines in wild and managed bees have raised global concerns about loss of pollination services. There is much evidence that diverse landscapes support a greater diversity of different pollinators than low diversity landscapes, but they also provide single species with a higher diversity of resources to exploit. However, little is known abo...
Poster
Full-text available
Worldwide, wild and managed Apis bees as the main pollinators of many plants are at a serious decline. Habitat loss is thought to play a major role in this decline, with diverse landscapes (comprising a variety of resources) most likely providing bees with a nutritional advantage over intensively farmed monocultures. However, little is known about...