Dog
The domestic dog functions as a self-regulating biological heating unit. With a core body temperature consistently 1-2 degrees higher than human normal, dogs radiate warmth continuously without requiring electrical connection or manual adjustment. A medium-sized dog produces approximately 70-80 watts of thermal energy during rest, equivalent to a small electric heater. This output increases dramatically during sleep, when dogs seek proximity to their owners with seemingly magnetic determination.
However, dogs present significant thermal inconsistencies. They relocate without warning. They respond to stimuli invisible to human perception, abandoning their post to investigate sounds, smells, or the inexplicable urgency that compels them to stare at walls. Their warmth, whilst substantial, is unreliably distributed.
Blanket
The blanket represents thermal engineering perfected through millennia of refinement. Modern blankets achieve thermal resistance values (tog ratings) precisely calibrated for seasonal requirements. A quality duvet at 13.5 tog provides insulation equivalent to wearing multiple layers of outdoor clothing whilst remaining stationary. The blanket stays where placed. It does not decide that 3 AM is an appropriate time to investigate kitchen noises.
Yet blankets generate no heat independently. They merely preserve existing thermal energy, meaning a cold human under a blanket remains cold until sufficient metabolic output raises the trapped air temperature. The initial contact, particularly in winter, can approach thermodynamic unpleasantness.
VERDICT
Whilst dogs produce active heat, blankets provide predictable, consistent coverage. One cannot be certain where a dog will position itself. One is entirely certain where a blanket remains.