What reflexes are there only in humans?

Reflexes are involuntary and automatic reactions of the body that are coordinated by nerve cells and serve to protect the body. In principle, a distinction must be made between two types of reflexes: innate reflexes and acquired reflexes.

A reflex that everyone knows from personal experience is the hamstring reflex. In the event of a light blow below the kneecap, the leg reacts with a rocking forward movement. But how do reflexes work?
A physical or chemical stimulus hits a sensory cell, the receptor. The receptor converts the stimulus into electrical signals (transduction). These impulses run through a afferent nerve fiber (afferent = leading to the central nervous system) ins Spinal cordwhere the processing of the stimulus takes place. Over a efferent nerve fiber (leading out) the signal finally reaches the Effector (mostly muscle cells). The motorized end plate transfers the electrical excitation from the nerve fiber to the muscle. As a result, it then comes to reaction, the contraction of the muscle.
This process is so quick and automatic that we are not aware of it. Most of the time, the brain is not involved at all. Controlled control of the innate reflexes is therefore also not possible.