Is a muscrat a homeothermic

No, a muskrat is not homeothermic; it is considered ectothermic, meaning its body temperature is regulated by the external environment rather than being constant. Muskrats are mammals that can maintain their body temperature to some degree, but they rely heavily on their surroundings. They adapt to seasonal changes by altering their behavior and habitat use, such as burrowing into the ground or building lodges in water.