As human beings, behaviours make up our everyday lives. What we do from the moment we wake up to the moment we go back to sleep at night can all be classified and studied through the concepts of behavioural ecology. The same applies to all vertebrates and, to some extent, invertebrates. Fungi are, in most people's eyes perhaps, the eukaryotic multicellular organisms with which we humans share the least commonalities. However, they still express behaviours, and we argue that we could obtain a better understanding of their livesalthough they are very different from oursthrough the lens of behavioural ecology. Moreover, insights from fungal behaviour may drive a better understanding of behavioural ecology in general.
Can fungi be studied through the lens of behavioural ecology?All organisms, be they prokaryotic or eukaryotic, macroorganisms or microorganisms, have to solve a similar set of basic problems to survive: how to obtain energy and nutrients, avoid being eaten or killed, and spread their offspring and how to partition resources between these activities [1]. To address these problems, they have all evolved different sets of solutions and behaviours (Figure 1 and Table 1).Fungi constitute a vast kingdom of 2-6 million or more species [2,3] (Box 1 and Table 1), but despite our rapidly increasing understanding of fungal genetics, biochemistry, cell biology and physiology, there are a surprisingly large number of gaps in our basic understanding of their lives and behaviours. We believe that fungal ecology would greatly benefit from being studied under the framework of behavioural ecology and that behavioural ecology, in turn, will benefit from the challenges of including fungi.Behaviour is not well defined in the literature, but broadly covers an organism's movements, interactions, cognition (see Glossary), and learning. Tinbergen introduced four classic ways of asking why an animal performs a certain behavioural act. How does the behaviour improve survival or reproduction? How has the behaviour changed over time? What factors lead to the behaviour seen in a specific instance? How does the behaviour in an individual change as it matures and which internal and external factors affect this? [4]. These questions are equally appropriate for fungi and through them we could gain a better understanding of the context in which fungi explore and forage for nutrients, interact with other organisms, and respond to their abiotic environment.