What happens to a reptile’s movement and heartbeat when environmental temperatures become too low?

Because reptiles are ectothermic (cold-blooded) animals, they rely on their environment to regulate their body temperature rather than generating heat internally.12

When environmental temperatures fall below a critical minimum, a reptile’s metabolic activity decreases significantly. This physiological shift results in several observable changes:2

• Movement: The reptile becomes sluggish and loses the ability to perform normal activities required for survival, such as hunting or escaping predators.2
• Heartbeat: The heart rate slows down.2
• Breathing: The rate of breathing drops.2

In these conditions, the animal becomes incapable of maintaining the normal functions necessary for growth and reproduction. During extended periods of cold, some reptiles may enter a state of dormancy known as brumation, which is characterized by inactivity and torpor. To avoid these negative effects, reptiles must typically move to an area with a higher ambient temperature to maintain their optimal thermal range.23