The research, published in Proceedings of the National Academy of Sciences, sheds light on the extreme ranges of heart rates in blue whales during diving, feeding and surfacing. "There were many palms and laps of victory in the laboratory".
The data also suggests that some unusual features of the whale's heart might help it perform at these extremes. Studies like this add to our fundamental knowledge of biology and can also inform conservation efforts.
In a Standford University press release, he said the whales might be particularly susceptible to changes in their environment that could affect their food supply, which could make studies like these key to the conservation of the endangered species. An increasingly vigorous cardiovascular framework isn't likely, they contend, and the new research may really clarify why no species on Earth has become greater than the blue whale.
Ten years ago, Professor Goldbogen and Mr Ponganis measured the heart rates of diving Emperor Penguins - and for had years wondered if they might do the same with whales. "Even today, they only represent about 10 percent of its pre-whale population worldwide".
Researchers noted that the tag performed well on smaller, captive whales, but getting it near a wild blue whale's heart is a different task. The team attached heart rate monitors to one whale with suction cups so they would stay secure as the animal lunged open-mouthed through the water collecting krill. They don't flip belly up like some other marine creatures, and the ripples of their accordion-like skin expand and contract as they feed, meaning that the tag could very easily come loose anyway.
And the lead author of the paper said they were trying to figure out what life is like when you're that big. "The only way to do it was to try. So we tried our best". The data it captured showed striking extremes. The dynamic tempo is what surprised the scientists most: models of resting heart rate based on size had suggested that the whale's should be somewhere around 11 beats a minute, and so the team expected there would be some period when its heart rate would hit this speed. When the whale surfaced to breathe and recover, its heart rate accelerated to 40 beats per minute. This nearly outpaced what the researchers expected, but it was the minimum heart rate that really caught the researchers by surprise, being around 30 to 50 percent lower than they'd expected. Between these low-tempo beats, the whale's stretchy aortic artery slowly contracted to keep oxygenated blood slowly moving through the animal's body, the researchers wrote. Meanwhile, impressively high rates may depend on subtleties in the movement and shape of the heart that prevent the pressure waves of each beat interrupting blood flow.
Simultaneously, the new investigation, co-wrote by sea life researcher Jeremy Goldbogen from the School of Humanities Sciences at Stanford University, recommends the blue whale has arrived at the biggest size feasible for a sea-going living being on Earth.
The heart of one beached blue whale found in 2015 weighed 400 pounds and appeared to be about the size of a golf cart, LiveScience reported. They also want to try their tag on other members of the rorqual whale group, such as fin whales, humpbacks and minke whales.
"A lot of what we do involves new technology and a lot of it relies on new ideas, new methods and new approaches", says Cade. "We're always looking to push the boundaries of how we can learn about these animals".
Other Stanford co-authors include graduate students Max Czapanskiy, James Fahlbusch, William Gough and Shirel Kahane-Rapport and fellow postdoctoral fellow Matt Savoca.