Dodder vines can grow toward host plants by following smell-like chemical cues.

Plants are easy to imagine as passive: rooted, slow, and unable to hunt. Dodder breaks that mental model. This parasitic vine starts life as a seedling that must find a host quickly. Experiments showed field dodder seedlings growing toward tomato plants and even toward extracted tomato volatiles when no plant was present. They could also distinguish between chemical blends from different plants. Dodder does not smell with a nose, and it is not chasing at animal speed. But it uses airborne chemistry to aim growth toward a victim, which is close enough to plant hunting to feel wrong.

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