How are the whales and dolphins able to stay longer underwater even if they have no gills?

Answer 1

Oxygen storage and utilization in cetaceans (whales) is largely affected by the wide range of body mass. It is the balance of storage and consumption of oxygen that defines the diving limits. This is maximized with the help of counter current systems and so-called retia mirabilia (or wonder net), which stores blood. Oxygen storage in muscles is a function of the myoglobin content, which in marine mammals is many times higher than in terrestrial mammals. In whales the myoglobin content in the longissimus dorsi (a muscle) ranged from 1.81 to 5.78 g per 100 g wet muscle as opposed to 1.0 g per 100g wet muscle in terrestrial mammals. Also, it was shown that the myoglobin content and body mass in whales are positively correlated in the “tooth whales” (odontoceti), whereas this is not the case in ballen whales (mysticeti). What this means is that odontocete whales have more myoglobin in more muscle, thus animals that have more muscle (are bigger) can also dive longer. In mysteceti, which hold the diving records in regards to depth and duration, muscle content is less of an indicator. In all whales, however, blood volume plays a significant role; blood volume is about 2-3 times higher in diving mammals than in land mammals.

Another important aspect is the great efficiency with which whales are able to vent their lungs and refill them (blue whales can vent an refill 1500 l of air in under 2 seconds). The gas exchange in the whale lung is extremely efficient, compared to that in land mammals (90% in whales as opposed to about 20% in land mammals). Nevertheless, the lungs will collapse under the enormous pressure of great depths. For whales, this is actually a good thing, since now the oxygen is taken from storage in the tissues (s.a.) and build up of dangerous nitrogen, an important mechanism to avoid nitrogen narcosis or decompression sickness (Bends).

As you can see, the physiology of whales is in many ways extremely well adapted to the problem of long and deep dives.

Please allow me a word or two regarding the conduct of answering questions. In particular I am referring to KrazyK784 and Joe Holloway. I think that regardless of what you think of the way people answer the questions in here you two should maintain a certain maturity and appropriate choice of language. While I understand KrazyK784’s frustration with at times useless additions to previous answers, I also share Joe Holloway’s point that additions are sometimes unavoidable in order to correct wrong answers and prevent confusion. However, if you do that, give the right answer. While Holloway describes an interesting “experiment” than can show you the difference of holding your breath with more oxygen stored in your blood as opposed to less, in whales this has nothing to do with learning. It’s a function of their physiology. Consequently, I would suggest that Holloway restrains himself from calling others names and instead does his homework!

Answer 2

Some dolphins can only stay under water for 30 seconds others can stay under for 30 minutes. its all about their capacity to hold air for longer periods of time. An experiment to try, take in a deep breathe and hold it as long as you can, and time it. Now take in a deep breathe and let if out slowly many times, after about a minute of doing this take in another deep breath and hold it, and time it. you will find you have increased your lung capacity. its about a learned body response they do it all their lives and soon after their first breath of air they need to surface less often. Also depends on what they are doing at the time. hunting needs more breath just moving around expends less air. oh and jack *** below me there metabolic rate is way off brother. Metabolic rate is the amount of energy expended in a give period. not oxygen jackass

Answer 3

Somehow, their bodies are manufactured to conserve the limited amount of air drawn in to allow for maximum time underwater. Of course, that's kinda obvious, but it's the best I can do :P

Answer 4

its called their metabolic rate. I hate how people try to sound smart and add extra stuff. Its the Metabolic rate. Humans can alter theirs alittle like pearl divers can be fine under water for over 3 minutes.

Answer 5

They do not have gills because they are mammals. Gills pull oxygen from the water. Mammals can't do that.

Answer 6

they have a huge capacity to store oxygen in the blood and lungs while diving. yet they must surface to breathe and the first thing they do when they surface is to exhale through the blowhole in the top of the head.

Answer 7

because its the way they were made