The genetics and movement of ecologically important migratory Hoverflies

Migration is a diverse and widespread phenomenon occurring throughout the animal kingdom on all continents of the earth. Insects are the most numerous terrestrial migrants, far surpassing vertebrates in terms of biomass and abundance, and have profound impacts on ecosystem processes, such as pollination, nutrient cycling, and pest regulation. While migration in mammal and bird species has been extensively studied, understanding the mechanisms underpinning insect migration and the ecological impacts of these movements remains a major goal in movement ecology and migration biology. This thesis aims to address some of these knowledge gaps, which I present here in four parts through published, peer-reviewed papers. Firstly, I explore the various roles of hoverflies as pollinators in our changing world, introducing new data regarding their economic importance, comparing their morphology to that of bee species, and discussing their migratory propensity. Next follows a study of the role of migratory hoverflies as long-distance pollen vectors, addressing key questions relating to pollen diversity and plant visitation networks, along with new insights into the migratory routes and distances over which pollen is vectored in northern Europe. Thirdly, I explore the role of genetics in the expression of migratory phenotypes in the marmalade hoverfly, Episyrphus balteatus. Through differential gene expression analysis of migrant and non-migrant female flies, I identify a variety of genes and pathways that are fundamental to the migratory phenotype. Lastly, I investigate the physiological, morphological, and genetic basis of female-skewed sex ratios, measured during field observations of active migrant hoverflies in the Pyrenees. Using this approach, I elucidate the mechanisms underpinning the diminishing population of males during the migratory journey and identify key female migratory traits required for long-distance migration.<p></p>

Author dc:creator

• Toby Doyle (22357153)

• Insect migration

Statement dc:rights

• All rights reserved

Identifier

10779/exe.31616980.v1

OAI identifier oai:identifier

oai:figshare.com:article/31616980