Long‐range seasonal migration in insects: mechanisms, evolutionary drivers and ecological consequences

Abstract

Myriad tiny insect species take to the air to engage in windborne migration, but entomology also has its 'charismatic megafauna' of butterflies, large moths, dragonflies and locusts. The spectacular migrations of large day-flying insects have long fascinated humankind, and since the advent of radar entomology much has been revealed about high-altitude night-time insect migrations. Over the last decade, there have been significant advances in insect migration research, which we review here. In particular, we highlight: (1) notable improvements in our understanding of lepidopteran navigation strategies, including the hitherto unsuspected capabilities of high-altitude migrants to select favourable winds and orientate adaptively, (2) progress in unravelling the neuronal mechanisms underlying sun compass orientation and in identifying the genetic complex underpinning key traits associated with migration behaviour and performance in the monarch butterfly, and (3) improvements in our knowledge of the multifaceted interactions between disease agents and insect migrants, in terms of direct effects on migration success and pathogen spread, and indirect effects on the evolution of migratory systems. We conclude by highlighting the progress that can be made through inter-phyla comparisons, and identify future research areas that will enhance our understanding of insect migration strategies within an eco-evolutionary perspective.

Key Questions in Marine Megafauna Movement Ecology

“…Future studies of the role of how predation risk shapes movement are important in light of declines in truly apex predatory species and the potential for predation risk to induce marine trophic cascades [60]. Furthermore, like predators, pathogens can also shape movement patterns in insects and birds [61] and might have this same impact in some marine taxa.…”

Long-distance autumn migration across the Sahara by painted lady butterflies: exploiting resource pulses in the tropical savannah

“…Long-range insect migration is a timely and important topic in ecological research but one that is still in its infancy [1]. With a few exceptions [2], the small size of insects has prevented the use of exogenous markers to track their movements, which means that the most basic aspects of migration, the route itself and the distances covered, remain poorly known for most species.…”

Genomewide transcriptional signatures of migratory flight activity in a globally invasive insect pest

“…2012, 2015). The behavioural, physiological and morphological adaptations necessary to undertake such flights form part of a much larger inherited ‘migratory syndrome’ which is present not only across the Insecta but also in other animal migrants such as birds and fish (Roff & Fairbairn 2007; Dingle 2014).…”