It's not accurate to say that certain stimuli *only* affect animals and not plants. Both animals and plants respond to a variety of stimuli, though their responses may differ.

Here's why:

* Plants respond to stimuli: Plants respond to light, gravity, touch, temperature, water, and even chemicals. They exhibit tropisms (directional growth in response to a stimulus) like phototropism (growing towards light) and gravitropism (growing against gravity). They also respond to touch (like the Venus flytrap closing) and chemicals (like a seed germinating in response to hormones).

* Animals have more complex responses: Animals have a nervous system that allows for more complex and rapid responses to stimuli. They can move quickly, learn and adapt to situations, and communicate with each other.

Here are some examples of stimuli that animals respond to more complexly than plants:

* Sound: Animals use sound for communication, navigation, and detecting prey/predators. Plants are less sensitive to sound.

* Social cues: Animals interact with each other, forming complex social hierarchies and patterns. While plants can communicate with each other chemically, they don't exhibit the same social complexity.

* Pain: Animals experience pain and have complex responses to it. Plants don't experience pain in the same way.

Important note: It's important to avoid anthropomorphizing plants by assuming they are not sentient or that they don't have complex internal processes. Research is constantly revealing new ways that plants interact with their environment.