The "beardies can't sense heat on their stomachs" debate

[spyder79]

ya know Barbara, I'm not even convinced that they seek the heat from above. I think that whether the heat source is from below or above, is irrelevant to them as they will thermoregulate their body temps no matter what. If they feel warm, then they feel warm.

I think the reason they seek the rays if the sun has nothing to do with heat but rather UV.

It would be more correct to say "that they do not sense heat as well from below as above."


I truely believe from watching some of my own beardies antics that they do not sense it from below as well as from above. I believe that it takes them longer to sense it from below, not that they don't. JMO

this is incorrect

they sense heat via a "probe" of sorts. The third eye also known as the Parietal eye. It is essentially a photosensory organ on the top of their skull. They use it to aid in thermo-regulation, light sensing, and it helps them disern possible threats from the sky.

 

[RedInkAus]

They seek heat from above simple experiment you guys can try is remove the basking light/heat source replace it with a regular energy saving bulb (a safe one that does not produce heat but merely light) and place a UTH in the are directly beneath the ligth source. You will find that the dragon though it will spend time on the area warmed by the UTH will still display basking behaviour from the non-heat emitting ligth source when provided a basking platform above the UTH.

Now this is not to say that they do not feel heat from below, they do just not as efficiently. The main reason for them seeking heat from above is their anatomy, reptile being ectotherms and solely reliant for an external source to warm themselves. The main blood vessels of BDs are on their back, the epidemis is also thinner on that area than the stomach with less concentration of blood vessels (hence the burn factor). This therefore allows the efficient transfer of warm blood to the rest of their bodies which is warmed on their backs. Therefore put simply it is more efficient for them to warm up with heat from above than from below which they will naturally seek (as any other diurnal reptile would, the process is reveresed in the nocturnal species).

MY 2 CENTS worth.

 

[GoFast]

But does that mean that they don't sense, or can't feel, heat from below??

ya know Barbara, I'm not even convinced that they seek the heat from above. I think that whether the heat source is from below or above, is irrelevant to them as they will thermoregulate their body temps no matter what. If they feel warm, then they feel warm.

I think the reason they seek the rays if the sun has nothing to do with heat but rather UV.

It would be more correct to say "that they do not sense heat as well from below as above."


I truely believe from watching some of my own beardies antics that they do not sense it from below as well as from above. I believe that it takes them longer to sense it from below, not that they don't. JMO

this is incorrect

they sense heat via a "probe" of sorts. The third eye also known as the Parietal eye. It is essentially a photosensory organ on the top of their skull. They use it to aid in thermo-regulation, light sensing, and it helps them disern possible threats from the sky.

Just thought I'd point out that heat from the sun at 1 metre of the ground has the same intensity as 100 metres above.

They seek heat from above simple experiment you guys can try is remove the basking light/heat source replace it with a regular energy saving bulb (a safe one that does not produce heat but merely light) and place a UTH in the are directly beneath the ligth source. You will find that the dragon though it will spend time on the area warmed by the UTH will still display basking behaviour from the non-heat emitting ligth source when provided a basking platform above the UTH.

Now this is not to say that they do not feel heat from below, they do. The main reason for them seeking heat from above is their anatomy. The main blood vessels of BDs are on their back, the epidemis is also thinner on that area than the stomach. Therefore put simply it is more efficient for them to warm up with heat from above than from below which they will naturally seek.

MY 2 CENTS worth.

Wouldn't it make more sense to place the non hat producing bulb on one side of the tank and the uth on the opposite end to see what one he chooses? Or am I misreading your post?

 

[RedInkAus]

But does that mean that they don't sense, or can't feel, heat from below??

ya know Barbara, I'm not even convinced that they seek the heat from above. I think that whether the heat source is from below or above, is irrelevant to them as they will thermoregulate their body temps no matter what. If they feel warm, then they feel warm.

I think the reason they seek the rays if the sun has nothing to do with heat but rather UV.

It would be more correct to say "that they do not sense heat as well from below as above."


I truely believe from watching some of my own beardies antics that they do not sense it from below as well as from above. I believe that it takes them longer to sense it from below, not that they don't. JMO

this is incorrect

they sense heat via a "probe" of sorts. The third eye also known as the Parietal eye. It is essentially a photosensory organ on the top of their skull. They use it to aid in thermo-regulation, light sensing, and it helps them disern possible threats from the sky.

Just thought I'd point out that heat from the sun at 1 metre of the ground has the same intensity as 100 metres above.

They seek heat from above simple experiment you guys can try is remove the basking light/heat source replace it with a regular energy saving bulb (a safe one that does not produce heat but merely light) and place a UTH in the are directly beneath the ligth source. You will find that the dragon though it will spend time on the area warmed by the UTH will still display basking behaviour from the non-heat emitting ligth source when provided a basking platform above the UTH.

Now this is not to say that they do not feel heat from below, they do. The main reason for them seeking heat from above is their anatomy. The main blood vessels of BDs are on their back, the epidemis is also thinner on that area than the stomach. Therefore put simply it is more efficient for them to warm up with heat from above than from below which they will naturally seek.

MY 2 CENTS worth.

Wouldn't it make more sense to place the non hat producing bulb on one side of the tank and the uth on the opposite end to see what one he chooses? Or am I misreading your post?

You can do that, the point being it would seek out the only heat source in it's enclosure but that being a UTH, it would not be the most efficient way of heating it self. Hence it will stay there longer to the point where it may burn itself due to the fact that it's stomach is not as sensitive and has less nerve endings and blood vessels. What you will find is that even if a UTH is it's only main source of heat it would still display the behaviour of basking for heat from above.

 

[foto69man]

Ok............so i'm with you on the blood vessels thing, but now i'm curious inregards to the color change. Is that tied into the heat deal? Or is that just purely light...? Anyone know? :study:

 

[RedInkAus]

Ok............so i'm with you on the blood vessels thing, but now i'm curious inregards to the color change. Is that tied into the heat deal? Or is that just purely light...? Anyone know? :study:

The colour change can be an expression of "mood" i.e. stress marks. As far as them going darker or lighter while basking it has to do with them thermoregulating, now I'm not a biologist so i can give you the exact scientific reason in terms of what happens anatomically. What i can offer is naturalistic behaviour observation, warm dragons are lighter and cold dragons are darker (easy test pick up yours when it's light and you'll feel it's physically warmer and vice versa). They darken to absorb more heat and when warm lighten to refelect more heat. Darker coloured clothing i.e black shirt is warmer in summer than a white shirt on your body same thing for them.

 

[citrusdragon]

I just saw this thread, and I must say that for a while I had been guilty of passing on this "urban legend". I agree that heat rocks are very unreliable, some of the newer UTH's are a little more so. I never recommend use of either, but I have seen circumstances when people can safely use UTH for their dragons, say when night temps drop for instance. I think they should not be used without a rheostat, and careful monitoring.

I think it is perfectly reasonable to assume too much heat from below would more harmful in an immediate sense than too much heat from above just because of the thickness of the scales. I find in general they like warmth, whether its your shoulder, a log, or a warms spot in the sand.

Recently, I have great success with my babies using a large cage with monitored ambient temps for my babies as apposed to a basking/cooling gradient. They don't dehydrate, they eat, they poop, and they grow. I find some babies are too dumb to leave the heat and dehydrate, and some are too shy and stay on the cool end only to be slow eaters/growers. I allow for night time drops to let the metabolisms rest.

I really just believe that too much heat whether from above or below is the problem we are addressing.
Heat rocks are very unreliable, as can be UTH, but the most unreliable part can be the person in control of the husbandry. There are more than one way to keep dragons, but as long as temps, UVB, and hydration (actually read a thread on a UK board that said they really don't need water dishes) are optimal dragons seem to thrive.

(thread on dragons and water http://www.reptileforums.co.uk/lizards/177301-your-bearded-dragon-its-habitat.html)

Good to hash this stuff out sometimes.

Jeff

 

[RedInkAus]

Recently, I have great success with my babies using a large cage with monitored ambient temps for my babies as apposed to a basking/cooling gradient. They don't dehydrate, they eat, they poop, and they grow. I find some babies are too dumb to leave the heat and dehydrate, and some are too shy and stay on the cool end only to be slow eaters/growers. I allow for night time drops to let the metabolisms rest.

Good to hash this stuff out sometimes.

Jeff

Standard husbandry practices in OZ is that 90% of keepers run wall mounted thermostats that only monitor air temps, air temps are always kept in the mid to high 20s by another source (CHE or extra light bulb). As long as basking temps don't exceed 45C we pretty much let the dragon thermoregulate itself through the natural temp gradient of the enclosure by moving to where it's comfortable.

 

[lacy_black]

I seem to remember this discussion from a couple years ago...some one (I forget his name now) was from australia and he said he used his temp gun on rocks in his yard on a really hot day and at most he found the temps were in the 90's on the rocks tho the air temps were over 100. (now that I think back he was alot like Brian :lol: not afraid of stepping on toes to give honest answers). So i'm not sure the "rocks in the wild are hot" theory really works.

 

[RedInkAus]

I seem to remember this discussion from a couple years ago...some one (I forget his name now) was from australia and he said he used his temp gun on rocks in his yard on a really hot day and at most he found the temps were in the 90's on the rocks tho the air temps were over 100. (now that I think back he was alot like Brian :lol: not afraid of stepping on toes to give honest answers). So i'm not sure the "rocks in the wild are hot" theory really works.

Depending on the actuall temps and time of day (plus the season) that would be about right. I can assure you though that reading would not have been taken at around mid-day. If the air temps is at over 100 (37C +) them it is guaranteed that the sun would have been blazing. By the time the sun fully heats up the rocks over a period of time they would be nudging the 140F + mark.

 

[Gail]

I seem to remember this discussion from a couple years ago...some one (I forget his name now) was from australia and he said he used his temp gun on rocks in his yard on a really hot day and at most he found the temps were in the 90's on the rocks tho the air temps were over 100. (now that I think back he was alot like Brian :lol: not afraid of stepping on toes to give honest answers). So i'm not sure the "rocks in the wild are hot" theory really works.

I remember that debate, had me running all over outside with a heat gun taking readings from rocks, asphalt, wood, what ever looked like a decent basking area for a large dragon. I can't remember any of the temps now, I should have wrote it down.

I have to agree that the argument about rocks being hot in the wild isn't very valid. A heat rock or UTH that stops working right will get way hotter then any rock you'll find in a dragons native habitat.

To answer the question as to whether this is a debate on snake forums, yes it is. On the corn snake forum I go to, I've read accounts of UTH or flexwatt malfunctioning and killing snakes. Unfortunately the only other option to heat a snake is a heat light but they are considered more dangerous in most instances.
A good snake keeper will be extremely diligent about checking temps daily and always use a rheostat.

It would be more correct to say that dragons can't sense heat well from the belly but some newbie would see that and think they could use a hot rock as long as they are careful. Its the same debate as feeding mealworms, will a mealie automatically kill your baby or cause malnutrition? no, but we tell people never to feed them because they are so "dangerous". Like posted before, better be safe then sorry.

 

[Livey]

i agree on the third eye,
i was told they detect heat from this, and it gives them information on how warm there body is?
as this not why they seem to sit upwards with there heads towards the heat?
as when i take her to the vets on the warm rice bag, she always puts her head on it,

 

[Beardiemommy137]

I think it's safe to say that we're not 100% sure as to how much heat that they sense from below but that it's not as much from above and that using a heat rock or heat cave or a UTH is unsafe because they can't be trusted now to short and cause severe injury to your dragon. Like someone said before, we don't know the exacts of what happens in the wild...and besides that these guys aren't wild.