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1. Leatherbacks have slighty larger than normal lung volume as compared to a generalized reptile scaled up to a leatherback's size, indicating that leatherbacks probably use lung stores during diving, especially shallow dives. For deeper dives leatherbacks have to push air out of their lungs into non-respiratory parts of their respiratory system (mainly bronchi) where little to no gas exchange can occur. This prevents atelectasis or collapse of aveoli due to the pressure applied on the lungs during a deep dive. (Paladino et al., 1996)

2. Since leatherbacks are not able to use oxygen stores in their lungs during deeper dives they have adapted other means of oxygen stores and transport. Leatherbacks have twice the blood oxygen carrying capacity of other sea turtles, and they have among the highest levels of hemoglobin and myoglobin for any reptile. (Lutcavage et al., 1992)

3. High levels of hemoglobin and myoglobin in active muscle tissues provide leatherbacks with a rapid oxygen delivery system, a large oxygen storage capacity, and rapid respiratory turnover when gas exchange is possible (Lutcavage et al., 1990). Not only do leatherbacks have great oxygen storage capacity, but they can also control their heart rate and shunt blood to efficeintly use thier store. Heart rate decreases when leatherbacks submerge and continue to decline at they reach greater depths (Southwood et.al, 1999). During deep dives they can keep most of their blood in their body core and away from their extremities, which keeps vital organs and muscles well oxygenated and also helps them to keep their bodies warm.

4. During excessively long dives, leatherbacks may have to respire anerobically. Anerobic respiration causes a build up of lactic acid in tissues and muscles, and also causes a build up of CO2. Like marine mammals, leatherbacks have a higher tolerance for large concentration of CO2, high pH, and lactic acid build up, which enables them to stay submerged longer than any other reptile (Lutcavage et al., 1992).

Unlike other sea turtles, leatherbacks are among the deepest diving vertebrates and have respiratory adaptations similar to other air breathing, diving vertebrates. While other sea turtles can only control their respiratory frequency, leatherbacks have the ability to adjust both depth and rate of breathing during activity and it allows them to be much more efficient and recover much faster after dives (Paladino et al., 1996). Along with their low metabolism and ability to control their breathing, leatherbacks have several more phsiological adaptations that allow them to be one of the best diving animals on the planet.