  Mutualistic interactions, where species interact to obtain mutual benefits,
constitute an essential component of natural ecosystems. The use of ecological
networks to represent the species and their ecological interactions allows the
study of structural and dynamic patterns common to different ecosystems.
However, by neglecting the temporal dimension of mutualistic communities,
relevant insights into the organization and functioning of natural ecosystems
can be lost. Therefore, it is crucial to incorporate empirical phenology -- the
cycles of species' activity within a season -- to fully understand the effects
of temporal variability on network architecture. In this paper, by using two
empirical datasets together with a set of synthetic models, we propose a
framework to characterize phenology on ecological networks and assess the
effect of temporal variability. Analyses reveal that non-trivial information is
missed when portraying the network of interactions as static, which leads to
overestimating the value of fundamental structural features. We discuss the
implications of our findings for mutualistic relationships and intra-guild
competition for common resources. We show that recorded interactions and
species' activity duration are pivotal factors in accurately replicating
observed patterns within mutualistic communities. Furthermore, our exploration
of synthetic models underscores the system-specific character of the mechanisms
driving phenology, increasing our understanding of the complexities of natural
ecosystems.
