- Chemical Ecology
- Nutritional Ecology
- Tropical Biology
- Behavioral Ecology
- Evolutionary Biology
- Bee-plant Interactions
Resource use by (social) insects.
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 on (at least) the insect's site. They have led (and still lead to) partly remarkably complex co-evolutionary adaptations which shape the ecology and life history traits of plants and insects alike. We are interested in the mechanisms by which insects exploit resources and how resources influence their (chemical) ecology, sensory adaptations, behavior, fitness and diversity.
Importance of resource diversity for stingless bees in Australia (DFG Project)
Biodiversity is known to be crucial for ecosystem functioning and stability. Moreover, species rich systems provide a diversity of resources to be exploited, with diversity on one level (e.g. primary producers/resources) strongly affecting other levels (e.g. consumers). But how resource diversity affects other species/ higher trophic levels that depend on these resources has been poorly investigated. We attempt to unravel the mechanisms by which resource diversity affects eusocial stingless bees. Stingless bees collect both floral resources (pollen and nectar) for nutrition, but also other plant materials (e.g. plant resins) for nest construction, nest defense and to build up their chemical body and nest profiles. They collect all these resources from various plant species available. We investigate whether this broad resource collection is by chance or adaptive and whether as well as how bees collecting in diverse ecosystems (e.g. rainforests, suburban habitats) gain a fitness advantage over bees collecting in less diverse habitats or even monocultures (e.g., macadamia plantations, eucalypt forests).
In collaboration with: Helen Wallace, Tim Heard
Plant resins – a neglected resource in the ecology of bees: How do resin plants and resin plant diversity influence bee colonies?
Bees are important pollinators of various plants, including many agricultural crop species. Hence, their decline has caused global concern. The highly social honey bees (Apis mellifera) and tropical stingless bees (Meliponini) play a particularly important role as pollinators. Besides nectar and pollen, these groups of bees also collect resin, a sticky substance that is produced by plants and has antimicrobial and repellent properties. Bees use resin for nest construction and defense against natural enemies and pathogens. Because of its antibiotic properties, people used the mixture of various resins and wax that is produced by honeybees (propolis) in traditional folk medicine for centuries. Consequently, research has focused primarily on the chemical composition and the biological activity of propolis, whereas little is known about the importance of resins for the bees themselves. But several studies have shown that resin deters bee parasites and pathogenes, such as the causative agent of American foul-brood (Paenibacillus larvae), the varroa mite (Varroa destructor) and the small hive beetle (Aethina tumida). A lack of resin sources or resin diversity and breeding of “resin-free” honeybees may thus be one reason for the global decline of honeybees.
Bees collect resins from tree wounds as well as from leaf buds, flowers and fruits of a multitude of plant species. Moreover, several stingless beee species transfer resin components to their body surface and thereby influence their chemical ecology. Consequently, plant resins represent an essential resource for these bees, and a lack of resin/ resin diversity may have a strong negative impact on colony health.
In this project, we study the origin of resin as well as the influence of resin and resin diversity on bee colonies.
In collaboration with: Alexandra-Maria Klein
(Tetrigona binghami collecting resin, Borneo)
Effects of degradation-resistent antibiotics used in veterinary medicine on plants, seed predators and pollinators (DFG Project)
In recent years, we have seen an increasingly intense use of antibiotics, which are primarily fed to livestock in order to prevent the outbreak of diseases in the densely populated farms of modern meat production. The extensive use of antibiotics has caused growing concern among scientists, and experts caution that the massive application of antibiotics does not only accelerate the evolution of resistant strains of pathogenic bacteria, but also increases the likelihood that antibiotics are transferred to the environment via manure or other types of waste. If antibiotics do not degrade immediately they may be taken up by other organisms, such as soil microbes or plants, and thus be distributed within the ecosystem with unknown consequences for its inhabitants. Given the lack of knowledge on the effect of antibiotics on plant-insect communities, the aim of this project is to investigate whether antibiotics that are taken up by plants are transferred to floral resources (i.e., pollen and nectar) as well as to leaves and whether they subsequently affect the plant’s interaction partners, i.e. herbivores and pollinators.
Consequences of land-use for solitary bee microbiota composition and function (MicroBEEs, DFG Project within Biodiversity Exploratories Priority Program)
When addressing land-use effects on plant-pollinator interaction networks, a major player has so far been largely ignored: Microbes. In MicroBEEs, we investigate how land-use induced changes in flowering plant composition and diversity affect bee-microbe interactions via changes in the species and nutritional composition of available floral resources. We combine network analyses of bee-plant (resource) and bee-microbe interactions with DNA-meta barcoding, shotgun metagenomics, laboratory assays and nutritional analyses. Our aim is to better understand which functions underlie interactions among and between mutualistic bee-microbe networks at both gene and taxonomic level. Specifically, we want to 1) disentangle bee-microbe networks in relation to land-use intensity and corresponding plant-bee diversity and network complexity, 2) define major functional genes of the bee microbiome, 3) experimentally verify the functional role of selected bacteria, and 4) assess how resource diversity and composition (and thus land-use intensity) affect the functional/taxonomic stability of (mutualistic) interactions.
Also see: Biodiversity Exploratories
How do bumblebees respond to and regulate food quality? (DFG Project)
The primitively eusocial bumblebees (Bombus spec.) are essential pollinators in temperate regions, but are threatened by anthropogenic activities that directly or indirectly affect the availability and diversity of flowering plants and hence the bees’ food sources. However, we still do not fully understand how resource availability and diversity and particularly their interactions with nutrient quality affect bumblebees. In a previous study, we could show that bumblebees collect a steady pollen diet of comparatively high protein content, suggesting that they regulate food quality. The aim of this project is to investigate (1) how bumblebees assess the nutrient content of food, (2) whether bumblebees compose a pollen diet with a specific nutrient composition and (3) whether diets deviating from this ratio negatively affect worker survival as well as colony growth and development.
In collaboration with: Johannes Spaethe
- Nicola Seitz, PhD student
- Fabian Rüdenauer, PhD student
- Birte Peters, PhD student
- Gemma Nydia Villagomez Garduno, PhD student
- Marie-Christin Bartsch, ZuLa Lehramt Gymnasium
- Julia Uhlein, ZuLa Lehramt Gymnasium
- Julia Burgrainer, ZuLa Lehramt Gymnasium
- Lukas Stegmann, ZuLa Lehramt Gymnasium
- Niklas Biewer, ZuLa Lehramt Gymnasium
- Maximilian Schiener, ZuLa Lehramt Gymnasium
- Victoria Steinert, ZuLa Lehramt Gymnasium
- Paula Östreicher, ZuLa Lehramt Gymnasium
- Holger Hanas, ZuLa Lehramt Gymnasium
- Leandra Blume, master student
- Samira Rösch, bachelor student
- Valentina Vey, bachelor student
- Stefan Sachs, master student and assistant
- Benjamin Kaluza, PhD student
- Nora Drescher, PhD student
- Julia Nagler, Diplom
- Frank Wenzel, ZuLa Lehramt Gymnasium
- Marietta Hülsmann, Master Lehramt
- Johanna Dotterweich, ZuLa Lehramt Gymnasium
- Linda Kriesell, ZuLa Lehramt Gymnasium
- Ronja Barth, ZuLa Lehramt Gymnasium
- Johannes Bader, ZuLa Lehramt Gymnasium
- Christine Wöhrle, ZuLa Lehramt Gymnasium
- Moritz Trinkl, ZuLa Lehramt Gymnasium
- Sara Repplinger, ZuLa Lehramt Gymnasim
- Nils Schmucker, bachelor student
- Catherine Cords, bachelor student
- David Sydow, bachelor student
- Nils Grund-Müller, master student
- Daniela Beierlein, master student
- Julia Meyer, ZuLa Lehramt Gymnasium
- Lisa Noack, ZuLa Lehramt Gymnasium
(45) Ruedenauer FA, Spaethe J, van der Kooi C & Leonhardt SD (2019) Pollinator or pedrigee: which factors determine the evolution of pollen nutrients? Oecologia (in press).
(44) Kämper W, Kaluza BF, Wallace HM, Schmitt T & Leonhardt SD (2019) Habitats shape the cuticular chemical profiles of stingless bees. Chemoecology (in press).
(43) Seitz N, vanEngelsdorp D & Leonhardt SD (2019) Conserving bees in destroyed landscapes: The potentials of reclaimed sand mines. Global Ecology and Conservation (in press).
(42) Drescher N, Klein AM, Schmitt T & Leonhardt SD (2019) A clue on bee glue: new insight into the sources and factors driving resin intake in honeybees (Apis mellifera). Plos One (in press).
(41) Pufal G, Memmert J, Leonhardt SD & Minden V (2018) Negative bottom-up effects of sulfadiazine, but not penicillin and tetracycline, in soil subtitute on plants and higher trophic levels. Environmental Pollution 245: 531-544.
(40) Ruedenauer FA, Spaethe J & Leonhardt SD (2018) Do honeybees (Apis mellifera) differentiate between different pollen types? Plos One 13(11): e0205821.
(39) Kaluza BF, Wallace HM, Heard TA, Minden V, Klein AM & Leonhardt SD (2018) Social bees are fitter in more biodiverse environments. Scientific Reports 8: 12353.
(38) Minden V, Schnetger B, Pufal G & Leonhardt SD (2018) Antibiotic-induced effects on scaling relationships and on plant element contents in herbs and grasses. Ecology and Evolution 8(13): 6699-6713.
(37) Leonhardt SD (2017) Chemical ecology of stingless bees. Journal of Chemical Ecology 43(4): 385-402.
(36) Kaluza BF, Wallace H, Keller A, Heard TA, Jeffers B, Drescher N, Blüthgen N & Leonhardt SD (2017) Generalist social bees maximize resource diversity intake in plant species rich and resource abundant environments. Ecosphere 8(3): e01758.
(35) Minden V, Deloy A, Volkert AM, Leonhardt SD & Pufal G (2017) Antibiotics impact plant traits, even at small concentrations. AoB PLANTS 9(2): plx010.
(34) Ruedenauer F, Leonhardt SD, Schmalz F, Rössler W & Strube-Bloss MF (2017) Separation of different pollen types by chemotactile sensing in Bombus terrestris. Journal of Experimental Biology 220: 1435-1442.
(33) Junker RR, Kuppler J, Amo L, Blande JD, Borges RM, van Dam NM, Dicke M, Dötterl S, Ehlers B, Etl F, Gershenzon J, Glinwood R, Gols R, Groot AT, Heil M, Hoffmeister M, Holopainen JK, Jarau S, John L, Kessler A, Knudsen JT, Kost C, Larue-Kontic AAC, Leonhardt SD, Lucas-Barbosa D, Majetic CJ, Menzel F, Parachnowitsch AL, Pasquet RS, Poelman EH, Raguso RA, Ruther J, Schiestl FP, Schmitt T, Tholl D, Unsicker SB, Verhulst N, Visser ME, Weldegergis BT & Köllner TG (2017) Co-variation and phenotypic integration in chemical communication displays: biosynthetic constraints and eco-evolutionary implications. New Phytologist DOI:10.1111/nph.14505.
(32) Drescher N, Klein AM, Neumann P, Yanez O & Leonhardt SD (2017) Inside honeybee hives: Impact of natural propolis on the ectoparasitic mite Varroa destructor and associated viruses. Insects 8(15): DOI:10.3390/insects8010015.
(31) Leonhardt SD, Kaluza BF, Wallace H & Heard TA (2016) Resources or landmarks: which factors drive homing success in Tetragonula carbonaria foraging in natural and disturbed landscapes? Journal of Comparative Physiology A 202(9): 701-708.
(30) Kriesell L, Hilpert A & Leonhardt SD (2016) Different but the same: bumblebee species collect pollen of different plant sources but similar amino acid profiles. Apidologie 48(1): 102-116.
(29) Kämper W, Werner PK, Hilpert A, Westphal C, Blüthgen N, Eltz T & Leonhardt SD (2016) How landscape, pollen intake and pollen quality affect colony growth in Bombus terrestris. Landscape Ecology 31(10): 2245-2258.
(28) Ruedenauer FA, Spaethe J & Leonhardt SD (2016) Individual bumblebees forage flexibly to collect high quality pollen. Behavioral Ecology and Sociobiology 70(8): 1209-1217.
(27) Leonhardt SD, Menzel F, Nehring V & Schmitt T (2016) Ecology and evolution of communication in social insects (Review article). CELL 164(6): 1277-1287.
(26) Kaluza BF, Wallace HM, Heard TA, Klein AM & Leonhardt SD (2016) Urban gardens promote bee foraging over natural habitats and plantations. Ecology and Evolution 6(5): 1304-1316.
(25) Wallace HM & Leonhardt SD (2015) Do hybrid trees inherit invasive characteristics? Fruits of Corymbia torelliana X C. citridorahybrids and potential for seed dispersal bees. Plos One 10(9): e0138868.
(24) Ruedenauer FA, Spaethe J & Leonhardt SD (2015) How to know which food is good for you: bumblebees use taste to discriminate between different concentrations of food differing in nutrient content. Journal of Experimental Biology 218: 2233-2240.
Inside article: jeb.biologists.org/content/218/14/2144.full
(23) Hülsmann M, von Wehrden H, Klein AM & Leonhardt SD (2015) Plant diversity and composition compensate for negative effects of urbanization on foraging bumblebees. Apidologie 46(6): 760-770.
(22) Leonhardt SD, Wallace HM, Blüthgen N & Wenzel F (2015) Potential role of environmentally derived cuticular compounds in stingless bees. Chemoecology 25(4): 159-167.
(21) Drescher N, Wallace HM, Katouli M, Massaro CF & Leonhardt SD (2014) Diversity matters: how bees benefit from different resin sources. Oecologia 176(4): 943-953.
(20) Leonhardt SD, Baumann A-M, Wallace HM, Brooks P & Schmitt T (2014) The chemistry of an unusual seed disperal mutualism: bees use a complex set of chemical cues to find their partner. Animal Behavior 98: 41-51.
(19) Massaro CF, Smyth TJ, Smyth WF, Heard T, Leonhardt SD, Katouli M, Wallace HM & Brooks P (2014) Phloroglucinols from anti-microbial deposit-resins of Australian stingless bees (Tetragonula carbonaria). Phytotherapy Research 29(1): 48-58.
(18) Leonhardt SD & Kaltenpoth M (2014) Microbial communities of three sympatric Australian stingless bee species. Plos One 9(8): e105718.
(17) Garibaldi LA, Carvalheiro LG, Leonhardt SD, Aizen MA, Blaauw BR, Isaacs R, Kuhlmann M, Kleijn D, Klein AM, Kremen C, Morandin L, Scheper J & Winfree R (2014) From research to action: practices to enhance crop yield through wild pollinators. Frontiers in Ecology and the Environment 12(8): 439–447.
(16) Leonhardt SD, Heard T & Wallace HM (2014) Differences in the resource intake of two sympatric Australian stingless bee species. Apidologie 45(4): 514-525.
(15) Leonhardt SD, Gallai N, Garibaldi LA, Kuhlmann M & Klein AM (2013) Economic gain, stability of pollination and bee diversity decrease from southern to northern Europe. Basic and Applied Ecology 14(6): 461-471.
(14) Leonhardt SD, Rasmussen C & Schmitt T (2013) Genes versus environment: geography and phylogenetic relationships shape the chemical profiles of stingless bees on a global scale. Proceedings of the Royal Society B 280: 20130680.
(13) Rushmore J, Leonhardt SD & Drea CM (2012) Sight or scent: lemur sensory reliance in detecting food quality varies with feeding ecology. Plos One 7(8): e41558.
(12) Leonhardt SD & Blüthgen N (2012) The same, but different: Pollen foraging in honeybee and bumblebee colonies. Apidologie 43(4): 449-464.
(11) Leonhardt SD, Form S, Blüthgen N, Schmitt T & Feldhaar H (2011) Genetic relatedness and chemical profiles in an unusually peaceful eusocial bee. Journal of Chemical Ecology 37(10): 1117-1126.
(10) Leonhardt SD, Schmitt T & Blüthgen N (2011) Tree resin composition, collection behavior and selective filters shape chemical profiles of tropical bees. Plos One 6(8): e23445.
(9) Leonhardt SD, Blüthgen N & Schmitt T (2011) Chemical profiles of body surfaces and nests from six Bornean stingless bee species. Journal of Chemical Ecology 37 (1): 98-104.
(8) Leonhardt SD, Wallace HM & Schmitt T (2011) The cuticular profiles of Australian stingless are shaped by resin of the eucalypt tree Corymbia torelliana. Austral Ecology 36: 537-543.
(7) Leonhardt SD, Zeilhofer S, Blüthgen N & Schmitt T (2010) Stingless bees use terpenes as olfactory cues to find resin sources. Chemical Senses 35 (7): 603-611.
(6) Leonhardt SD, Jung LM, Schmitt T & Blüthgen N (2010) Terpenoids tame aggressors: role of chemicals in stingless bee communal nesting. Behavioral Ecology and Sociobiology 64 (9): 1415-1423.
(5) Leonhardt SD, Blüthgen N & Schmitt T (2009) Smelling like resin: terpenoids account for species-specific cuticular profiles in Southeast-Asian stingless bees. Insectes Sociaux 56 (2): 157-170.
(4) Leonhardt SD & Blüthgen N (2009) A sticky affair: resin collection by Bornean stingless bees. Biotropica 41 (6): 730-736.
(3) Leonhardt SD, Tung J, Leal M & Drea CM (2008) Seeing red: behavioral evidence of trichromatic color vision in strepsirrhine primates. Behavioral Ecology 20 (1): 1-12.
(2) Leonhardt SD, Brandstaetter AS & Kleineidam CJ (2007). Reformation process of the neuronal template for nestmate recognition cues in the carpenter ant (Camponotus floridanus). Journal of Comparative Physiology A – Neuroethology, Sensory, Neural and Behavioral Physiology 193 (9): 993-1000.
(1) Leonhardt SD, Dworschak K, Eltz T & Blüthgen N (2007) Foraging loads of stingless bees and utilisation of stored nectar for pollen harvesting. Apidologie 38 (2): 125-135.
(3) Leonhardt SD (2015) To be(e) down under. Bienen und ihre Gefährdung in Australien. In Lorenz, Stephan/ Stark, Kerstin (Hg.): Menschen und Bienen. Ein nachhaltiges Miteinander in Gefahr. München: Oekom-Verlag (i.E., 4.6.15).
(2) Leonhardt SD (2010) When bees smell like trees: stingless bees with resinous perfumes. Aussie Bee Online Article 15.
(1) Leonhardt SD (2008) Botschaften aus Borneo. Spektrum Online Online Blog: www.spektrum.de/alias/botschaft-aus-borneo/965856
Associate Editor for the Journal of Insect Conservation.