True an iguana is not the same as a ball python, nor does it respond the same to environmental stimulants. However, if we are talking about reptile health, I believe we can make several comparisons. The main comparison is regarding the digestive mechinism of ectotherms. In an ectothermic system, organisms are unable to produce their own heat, and thus they must seek out heat from their environments (the sun). If sufficient heat is not generated, the organ systems slow down, and processes such as respiration, excretement, and digestion, are also minimalized until a general source of energy influxes.
Now most reptiles bask, or partake in specific behavioral adaptations to generate heat. Archosaurs (the main line of reptiles whose decendents include: crocs, aligators, dinosaurs, and birds) have a higher activity level, body temperature and faster metabolism than other reptiles. Crocs and birds(subclass avies) have a 4 chambered heart, and Avies also have an endothermic homeostatic system! Hence the reason my baby Opie (cockatiel) doesn't need to bask.
Now that I've spewed out a reptiles overall natural history, lets talk about the ball/royal python's!
During daylight hours wild ball pythons are most often found in abandoned termite mounds and rodent burrows. Termites are extremely sensitive to areas of high heat and low humidity, so they set up their mounds to have high humidity and low temps. At night the snakes tend to become more active, and are often times found wandering through forest/savanah transitional zones (in search of rodents). Ball pythons like many snakes, are almost never collected in areas of constantly high humidity (they chose to stay with in transitional zones which allow the snakes to frequent any particular zone depending on their physical and social needs).
So, yes a ball python, sand boa, leopard gecko, argentine horned frog...whatever you wish, are all different, and require different set-ups. However, in general these animals all want the same thing...the ability to control their internal environment! Now in my opinion heat pads should be used in conjunction with an overhead light..thus allowing the snake to have both ground and "atmospheric" heat (that way a warm snake isn't forced to breathe in cool air....something that would almost never happen in the wild).
Breeders who use a rack system are perfectly correct in saying that a heat pad is the best bet for their snakes (in general individual containers in a a rack are not as large as some pet aquariums..for example I have a 65 gallon aquarium with a screen top..I need to set up my tank in response to low humidity...and make sure my heating is sufficent...this is very different than a 30 gallon fully enclosed rubbermaid..typically found in a rack system...I have another ball set up in one of these that uses only a heat pad, and it works great becuase the cage is less ventilated and allows less heat to escape.
Now for the arguement that snakes do not bask...I beg to differ. I've witnessed snakes basking during the daylight hours and not only through my fun filled viewing of nature shows such as the slightly set up croc hunter and corwin! LOL! Hmmm look at this rare endangered venemous snake just sitting on a rock hahaha! But in reality, I've spent the last 4 and a half years of my life studying biology in college, and I spent a semester studying reptiles. We've seen racers, brown snakes, garters, and even corns and black rats out basking on rocks....granted once they caught us spying on them they were off! It is wrong to say that a terrestrial snake will never bask...granted it is not likely to see a ball out in the open in the wild!
Fossorial and subterrian in essence are the same term. Ball pythons are mainly terrestrial snakes with fossorial habits.
So, what's better heat pad, or spot light....I say if you have an aquarium use 'em both with a handy dandy digital heating device letting you know how hot it is! But if you just use a spotlight...you should be perfectly fine if your temps are suitable! Believe it or not..when my snakes are under a rock and there is a spotlight above it...the rocks do warm up!
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*Amy*
0.1 Green Iguana (yes, I have a lizard in my bathroom)-iggy
2.1 Ball Pythons (normal)-cosi, jake, and frosty mcfry
0.1 B.smithi (mexican redknee tarantula)-athena
0.0.1 midland painted turtle-nemo
1.1 dogs-rocky and skippy
1.0 normal grey cockatiel-opie
0.0.30 betta, guppies, rosy reds, fantail goldfish, clown pleco,...
1.1 Feeder mice- gremlin, chow (and future pups)