Plants make poisons to stop animals from eating them, because if they get eaten, they die.

This study shows that mice get sick from eating acorns because of tannins, a natural chemical in plants, but they can adapt better in cold weather — proving that plants make chemicals to hurt herbivores, and animals have to work hard to survive them.

Plants make chemicals like lignans to protect themselves from being eaten, and this study shows these chemicals affect our bodies — sometimes in helpful ways — which supports the idea that plants make these compounds to mess with animals that try to eat them.

Plants make special chemicals to protect themselves from bugs eating them, and these chemicals can also be harmful to animals like mammals—even if this study didn’t test mammals directly, it shows these chemicals exist for defense, which matches the claim.