Novel weapons and allelopathy in plant invasion

Published in New Phytologist (2025) — Colautti & Antunes

These figures accompany a critical reassessment of the novel weapons hypothesis; the long-standing idea that invasive plants succeed in their new ranges because they release biochemicals that native species haven't co-evolved defenses against. The paper asks whether allelopathy really does function as an adaptive strategy facilitating invasion, or whether the evidence is thinner than the popular narrative suggests.

The illustration depicts competitive interference between a canonical allelopathic invader, garlic mustard (Alliaria petiolata), and a native North American tree it is often accused of suppressing, sugar maple (Acer saccharum). The figure visualizes the chemical and ecological pathways at play both below and above ground, helping readers hold both the proposed mechanism and the ecoevo context of chemical interference.