No; they have no mechanism by which they regulate or maintain a specific temperature. They tend toward the ambient temperature of their surroundings.
A thermostat is supposed to maintain a constant temperature or temperature range in an area or for a device.
Warm blooded animals can maintain a constant body temperature.
Regulate
How do are body's maintain a constant temperature?
homeostasis
To maintain constant the temperature if necessary.
No. A spider has no mechanism to maintain its body temperature.
xsar
If the temperature of the gas is decreasing, then in order to maintain constant pressure, you would have to compress it in volume.
Endothermic animals maintain constant body temperature in a number of ways. One way is to lay out in the sun.
Warm-blooded animals.
By staying in the sun because the are cold blooded.