Arbuscular mycorrhizal (AM) fungi are important plant symbionts widespread worldwide. Like other fungi, they have the ability to perform hyphal anastomosis, that is, the fusion of encountering vegetative hyphae. Research in other fungal phyla has evidenced numerous potential functional and evolutionary consequences of anastomosis. Yet, in AM fungal research, anastomosis has almost strictly been discussed in the context of fungal response to disturbance and interindividual genetic exchange. Here, I review more broadly the implications of anastomosis for AM fungal ecology and evolution. I also identify major knowledge gaps and research prospects to better ground hyphal anastomosis strategies of AM fungi in their general life-history strategies.