Hi! I was researching ectotherms and was surprised to see Dinosaurs are now considered Mesotherms? Can you explain the difference I am a bit confused on how mesotherms regulate temperature. Apparently some monotremes are mesotherms which is also confusing since there is a very small pool of that species?
Okie let's see, hopefully I'm understanding and explaining it right.
Metabolism is what we call the chemical processes in our bodies that "keep the train running". These processes generate heat. But some animals have developed a way to increase this heat production and to use it to their benefit.
Endotherm means "inside heat", as the body's temperature is regulated from within. Our bodies maintain a stable temperature by generating lots of heat using metabolism. When its a little too hot or cold we sweat and shiver in order to quickly change the direction our temperature is going and to bring it back to the standard degree.
Ectotherm means "outside heat", referencing that the temperature outside the body is more or less the same as the temperature inside the body. These animals rely on their surroundings to maintain their body temperature, so they have to actively regulate it themselves. This is why reptiles and amphibians will go into the sunshine for warmth and into the shade to cool down.
Mesotherm means "intermediate heat", so they have a bit of both. They may generate more heat from metabolism than ectothermic animals, but its still not up to the level of an endotherm.
From the examples I saw, it seems like mesotherms are animals with unusual thermoregulation for their "group." An animal thats would be considered "normally ectothermic" having a way of keeping its body at a higher temperature range. Or "normally endothermic" animals with a very low temperature compared to others. I'm unsure how dinosaurs fall into mesotherms, whether they would be considered more of a "strange ectotherm" or a "strange endotherm ".
Some examples of animals considered mesotherms:
The leatherback sea turtle has a high temperature due to being extremely active, which generates a lot of body heat.
Tuna can trap the heat generated from their low metabolism, giving them an unsually high body temperature.
The echidna has a low body temperature for a mammal, but still relies on heat generated by their metabolism. To conserve energy, they will stop their thermoregulation and become dormant.
Naked mole rats lack normal endothermic thermoregulation because they live in low oxygenated areas underground. So, instead of using lots of oxygen to stay warm they will huddle together to share body heat.
