Communication with dolphins is getting better all the time — they've been using iPads, for one thing, and humans have been working on a type of Rosetta Stone-like two-way translation device. A new gadget could improve matters even further, by allowing humans to produce the full range of dolphin sounds. The acoustics researchers who developed it call it the Dolphin Speaker.

Dolphins Using the IPad

To better understand how these sounds are produced, how they travel and even what they mean, researchers need to be able to play them back, watching how dolphins react. This speaker can do it, producing sounds from 6 kHz to 170 kHz. While others have worked in the low-frequency ranges, this is the first type that can cover the whole spectrum.

Researchers led by Yuka Mishima, a graduate student at Tokyo University of Marine Science and Technology, built a new transducer sandwiched between pieces of acrylic to keep it safe from water. A quadruple piezoelectric panel can broadcast high-frequency sounds, and a single silver circle broadcasts low-frequency sounds.

Dolphin Speaker

The Dolphin Speaker is the first underwater setup that can project the full range of sounds made by dolphins, potentially opening a new avenue for communication with the animals.  They took it to the ocean and played some dolphin sounds, comparing the sound spectrograms with natural recorded spectrograms obtained from dolphins. The charts looked mighty similar, the researchers say. The next step is to play back a whole sequence of dolphin noises to dolphins and watch what happens.

Plenty of work is being done with dolphin sounds, but they have mostly focused on dolphin vocalizations and their hearing anatomy. Dolphins can not only hear and produce clicks, whistles and burst pulses well outside of the range of human hearing, but they can vocalize at several different frequency ranges at once. This ocean broadband is key for communication and navigation.

Things We Can Learn From Dolphins: Electro-Sensing, Amazing Powers of Healing

When we figure out how to communicate with dolphins pretty soon, these are some good questions to ask: Why don't you feel any pain when you're hurt? Can you teach us how to regrow missing body parts? And can you teach us how to sense electricity?

Dolphin Electro-Whiskers

The dots on this dolphin's rostrum are hairless vibrissal crypts, structures originally associated with mammalian whiskers, which serve as electroreceptors.  These are some of the latest impressive attributes we humans have learned about dolphins.  The animals can do much more than echolocate — they can sense the electric fields of other animals, according to a new study. This is mostly used to detect prey, although it might be useful for evading attacks. The Guiana dolphin has electro-whiskers in its rostrum, or dolphin nose, according to German researchers.

Dolphin Testing

Researchers at the University of Rostock noticed physiological activity in the upper jaw of the dolphins, located in pores called vibrissal crypts. These pits are normally associated with whiskers, the scientists explain in a new research paper. They examined a dead dolphin and found a nerve structure that resembled electroreceptors in other species. Fish, some amphibians and duck-billed platypuses possess these structures, but no other mammals do, according to New Scientist.  To make sure this wasn't just a vestigial anatomical structure left over from evolution, the researchers tested a 28-year-old male Guiana dolphin. They found the dolphin could detect a weak electric field, 4.6 microvolts per cm-1. Then they attached a plastic shell over his rostrum and tried it again, to find out whether covering up the vibrissal crypts would have any effect. He could not sense the electric fields, even at much higher intensities.  Electrosensing could help dolphins find prey at short distances, such as buried in sand, where echolocation wouldn't be of much use according to researcher Wolf Hanke.The study also suggests that other animals, especially aquatic animals, might possess these electro-whiskers and can act as animal Conduits. The paper is published in the Proceedings of the Royal Society B.

Dolphins apparently possess amazing regenerative capabilities, which could inspire new anti-bacterial treatments and wound healing for humans.  NPR's health blog talked to surgeon Michael Zasloff, who has discovered compounds in shark skin that can fight human diseases. Apparently dolphins can heal quickly and painlessly from shark bites, and they use stem cells to rebuild missing tissue. If a shark were to bite a chunk out of a dolphin, it would not hemorrhage or get infected, and apparently the dolphin would not even feel any pain, Zasloff said.  "Despite having sustained massive tissue injury, within about month the animal will restore its normal body contour. There'll be some surface markings, but a chunk of tissue maybe the size of a football will have been restored with essentially no deformity. Dolphin blubber has special compounds that act as natural antibiotics, and it must contain stem cells that are able to construct a flesh patch" said Zasloff.  He recently reviewed some amazing dolphin recovery stories in the Journal of Investigative Dermatology.  Unlocking these secrets will require much more dolphin research, Zasloff said. And even more motivation to get dolphins using the iPad.