  Aim: Spatio-temporal processes play a key role in ecology, from genes to
large-scale macroecological and biogeographical processes. Existing methods
studying such spatio-temporally structured data either simplify the dynamic
structure or the complex interactions of ecological drivers. This paper aims to
present a generic method for ecological research that allows analysing
spatio-temporal patterns of biological processes at large spatial scales by
including the time-varying variables that drive these dynamics. Methods: We
introduce a method called relational event modelling (REM), which relies on
temporal interaction dynamics, that encode sequences of relational events
connecting a sender node to a recipient node at a specific point in time. We
apply REM to the spread of alien species around the globe between 1880 and
2005, following accidental or deliberate introductions into geographical
regions outside of their native range. In this context, a relational event
represents the new occurrence of an alien species given its former
distribution. Results: The application of REM to the first reported invasions
of 4835 established alien species outside of their native ranges from four
major taxonomic groups enables us to unravel the main drivers of the dynamics
of the spread of invasive alien species. Combining the alien species first
records data with other spatio-temporal information enables us to discover
which factors have been responsible for the spread of species across the globe.
Besides the usual drivers of species invasions, such as trade, land use and
climatic conditions, we also find evidence for species-interconnectedness in
alien species spread. Conclusions: REM offer the capacity to account for the
temporal sequences of ecological events such as biological invasions and to
investigate how relationships between these events and potential drivers change
over time.
