Research interests

  • Pollination Ecology and Chemical Ecology in Neotropical Orchids
  • Floral Scents
  • Animal- Plant Interactions
  • Electrophysiology in Insect Olfaction
  • Evolutionary Ecology

Scientific projects

The role of floral scents in pollinator attraction of the neotropical orchid genus Catasetum

Flowers of the species-diverse neotropical genus Catasetum produce no nectar or pollen as rewards for their pollinators. Instead, male euglossine bees visit these orchids to acquire species-specific blends, which are most likely exposed in perching sites during courtship display. While visiting male flowers of Catasetum, a catapult-like apparatus can be triggered, resulting in the attachment of the pollinarium to the males’ body. If this male subsequently visits a receptive female flower, this may result in pollination. In orchids as a whole and in perfume-producing orchids specifically, floral scents are considered to be one of the most important cues in attracting bees to flowers.

In order to comprehend better the evolution of floral scents in Catasetum, it is necessary to gather a species-representative sampling of floral scent constituents for the genus and to establish the behavioural significance that compounds play in attracting pollinators. In my PhD thesis, I aim to clarify the pollination system of the genus Catasetum and to gain further knowledge on the role of floral scent constituents for pollinator attraction and the sensory and behavioural responses volatiles trigger in their euglossine pollinators.


Brandt K, Dötterl S, Ramírez SR, Etl F, Machado IC, Navarro DMAF, Dobler D, Reiser O, Ayasse M, Milet-Pinheiro P Unraveling the Olfactory Biases of Male Euglossine Bees: Species-Specific Antennal Responses and Their Evolutionary Significance for Perfume Flowers  Frontiers in Ecology and Evolution, Volume 9, doi: 10.3389/fevo.2021.727471
Brandt K, Machado IC, Navarro DMAF, Dötterl S, Ayasse M, Milet-Pinheiro P (2020) Sexual dimorphism in floral scents of the neotropical orchid Catasetum arietinum and its possible ecological and evolutionary significance, AoB PLANTS, Volume 12, Issue 4, August 2020, plaa030,

Steitz I, Brandt K, Biefel F, Minat Ä, Ayasse M (2019) Queen Recognition Signals in Two Primitively Eusocial Halictid Bees: Evolutionary Conservation andd Cast-Specific Perception. Insects 2019, 10, 416 . doi: 10.3390/insects10120416

Brandt K, Dötterl S, Fuchs R, Navarro DMAF, Sobreira Machado IC, Dobler D, Reiser O, Ayasse M, Milet-Pinheiro P (2019) Subtle chemical variations with strong ecological significance: Stereoselective responses of male Orchid Bees to stereoisomers of carvone epoxide. Journal of Chemical Ecology 45: 464–473 , 

Brandt K, Dötterl S, Francke W, Ayasse M, Milet-Pinheiro P (2016) Flower visitors of Campanula: Are oligoleges more sensitive to host-specific floral scents than polyleges? Submitted in: Journal of Chemical Ecology

Conference contributions

Dering(Brandt) K, Dötterl S, Ayasse M, Milet-Pinheiro P: Antennal sensitivity to floral scents of Campanula: A comparative study of polylectic and oligolectic bees. 11. Hymenopterologentagung, Stuttgart, Germany (Poster)

Dering(Brandt) K, Dötterl S, Ayasse M, Milet-Pinheiro P: Antennal sensitivity to floral scents of Campanula: A comparative study of polylectic and oligolectic bees. Entomologentagung der DGaaE 2015, Frankfurt/Main, Germany (Talk)


Dr. Katharina Brandt
Institute of Evolutionary Ecology and Conservation Genomics
Ulm University
Albert-Einstein-Allee 11
D-89081 Ulm, Germany
Tel. +49 (0)731 50 22696
Fax +49 (0)731 50 22683