Dolphins

Includes orcas

The so-called “dive response” is not merely a reflex in dolphins, but an active response.

Why aren’t dolphins getting bent?

Marine mammals are not above the physical principles and processes that lead to bubble formation in tissues following decompression. Scientists once thought that diving marine mammals were immune from decompression sickness, but beached whales have been found to have gas bubbles in their tissues—a sign of the bends. In any case, how some marine mammals and turtles can repeatedly dive as deep and as long as they do has perplexed scientists for a very long time.

Swimming with dolphins
Swimming with and learning from dolphins

Learning the swimming secrets of dolphins and whales

This scenario may one day become reality. And to be efficient, such robots would need to be maneuverable and stealthy, and be able to closely mimic the movements of the marine creatures.

Scientists like Keith W. Moored are working on the next generation of underwater robots by studying the movements of dolphins and whales. "We're studying how these animals are designed and what's beneficial about that design in terms of their swimming performance, or the fluid mechanics of how they swim."

Dolphins use a double sonar

“The findings add fuel to an already fierce debate in the research community on how the echolocation sound is produced”, says Josefin Starkhammar.

Dr Starkhammar’s own guess is that the two sound projections come from the two different sound-producing organs, the existence of which is well known, but it was believed that only one was active during echolocation. She stresses that more research is needed. For example, the two projections could also be explained by complicated reflections in the head of the dolphin, where the sound is formed.

The beam projections have different frequencies and can be sent in different directions. The advantage is probably that the dolphin can locate the object more precisely.

—Josefin Starkhammar