This one really is kind of a no-brainer if you think about it. There really is no room for discussion, (hatchling right to retiree) or at least intelligent discussion in my opinion...
Since ball pythons spend..ahh..100% of their life on their bellies it only seems logical for belly heat to be the most logical (and efficient) use of heat.
If someone could breed spider balls that were gravity-defying and can hover against the back of their bins 3 inches off the ground, then back heat would be best.
The only arguement against belly heat you could possibly get would be from the keepers who don't want to pay the extra for the heat tape needed for belly heat, or take the time to run belly heat.
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