Photo: Marinus de Jager

© 2016 biological interactions

Postdoc with B Anderson

Department of Botany and Zoology


biological interactions

Dr Marinus L. de Jager

My main interest lies in the processes that generate and maintain biological diversity. After completing my undergraduate degree in Biodiversity and Ecology at Stellenbosch University, I explored the influence of pollinators on the assembly of plant communities in South Africa. Next, I focused on the incredible case of sexual deception in the daisy, Gorteria diffusa. The experimental nature of this research fascinated me and consequently my PhD dealt mainly with the interactions between this hyper-diverse species and its insect pollinators and florivores. Coupled with extensive fieldwork, I also investigated the evolutionary history of its dominant pollinator in order to integrate molecular data into hypotheses about diversification within this system. Since my PhD, I have conducted collaborative research with various scientists at the University of Cambridge, the Australian National University and the University of KwaZulu-Natal. Although primarily a pollination biologist, I have also studied and published on herbivory and pest ecology, behavioural ecology and community ecology. I intend to keep learning about our natural world and share what I find.


Since my PhD, I have often worked on the ecology of orchids, which comprise research collaborations with Prof. Rod Peakall in Australia and Prof. Steve Johnson in South Africa. I am also involved with a project on foraging and learning dynamics in bees with Prof. Beverly Glover at Cambridge University. Currently, I am working with Prof. Bruce Anderson at Stellenbosch University on pollination ecosystem services delivered to the Western Cape horticultural industry, specifically in blueberry cultivation. I am also exploring the impacts of co-flowering species on plant reproduction. This work entails investigating both facilitative and competitive interactions among plant species that share pollinators, and ties in with my work on plant community restoration. With my research, I aim to combine the power of experimental biology with the expansive scope of community ecology in order to identify processes that affect plant fitness at multiple scales.

Current Research

De Jager ML, Peakall, R. 2018. Experimental examination of pollinator-mediated selection in a sexually deceptive orchid. Annals of Botany. link


De Jager ML, Ellis AG. 2017. Evolutionary history of a keystone pollinator parallels the biome occupancy of angiosperms in the Greater Cape Floristic Region. Molecular Phylogenetics and Evolution 107: 530-537. pdf


De Jager ML, Willis-Jones E, Critchley S, Glover, BJ. 2016. The impact of floral spots and rings on pollinator foraging dynamics. Evolutionary Ecology: Special Edition. pdf


De Jager ML, Newman E, Theron G, Botha P, Barton M, Anderson B. 2016. Pollinators can prefer rewarding models to mimics: Consequences for the assumptions of Batesian mimicry. Plant systematics and Evolution 302: 409–418. pdf


De Jager ML, Peakall R. 2015. Does morphology matter? An explicit assessment of floral morphology in sexual deception. Functional Ecology 30: 537–546. pdf


De Jager ML, Ellis AG. 2014. Costs of deception and learned resistance in deceptive interactions. Proceedings of the Royal Society B. B 281:20132861. pdf


De Jager ML, Ellis AG. 2014. Floral polymorphism and the fitness implications of attracting pollinating and florivorous insects. Annals of Botany 113: 213–222. pdf


Ellis AG, Brockington SF, De Jager ML, Mellers G, Walker RH, Glover BJ. 2014. Floral trait variation and integration as a function of sexual deception in Gorteria diffusa. Philosophical transactions of the Royal Society B. 369: 20130563. pdf


De Jager ML, Ellis AG. 2013. The influence of pollinator phylogeography and mate preference on floral divergence within a sexually deceptive daisy. Evolution 67: 1706-1714 pdf


De Jager ML, Ellis AG. 2012. Gender-specific preference for floral traits. Functional Ecology 26: 1197-1204. pdf


De Jager ML, Dreyer LL, Ellis AG. 2011. Do pollinators influence the assembly of flower colours within plant communities? Oecologia 166: 543-553. pdf


de Merxem DG, Borremans B, De Jager ML, Johnson T, Jooste M, Ros P, Zenni RD, Ellis AG, Anderson B. 2009. The importance of flower visitors not predicted by floral syndromes. South African Journal of Botany 75: 660-667. pdf