Science Current Events | Science News | Brightsurf.com
 

Study Amplifies Understanding of Hearing in Baleen Whales

April 18, 2012
For decades, scientists have known that dolphins and other toothed whales have specialized fats associated with their jaws, which efficiently convey sound waves from the ocean to their ears. But until now, the hearing systems of their toothless grazing cousins, baleen whales, remained a mystery.

Unlike toothed whales, baleen whales do not have enlarged canals in their jaws where specialized fats sit. While toothed whales use echolocation to find prey, baleen whales generally graze on zooplankton, and so some scientists have speculated that baleen whales may not need such a sophisticated auditory system. But a new study by scientists at Woods Hole Oceanographic Institution (WHOI), published April 10, 2012, in The Anatomical Record, has shown that some baleen whales also have fats leading to their ears.

The scientists propose that toothed whales may not be the only whales that use fats to transmit sound in water, as previously believed, and the fats in both types of whales may share a common evolutionary origin.

Little progress had been made on the auditory anatomy of baleen whales because specimens to study are hard to get. Unlike many toothed whales, they are large, not kept in captivity, rarely strand on beaches, and decompose rapidly when they do.

For the new study, lead author Maya Yamato, a graduate student in the MIT/WHOI Joint Program in Oceanography, received seven heads of minke whales that stranded and died, mostly on beaches on Cape Cod. She collaborated with the International Fund for Animal Welfare's (IFAW) Marine Mammal Rescue and Research unit in Yarmouth Port, Mass.

The whale heads were scanned using computerized tomography (CT) and magnetic resonance imaging (MRI) at the Computerized Scanning and Imaging (CSI) lab at WHOI and MRI facility at Massachusetts Ear and Eye Infirmary in Boston. Using these biomedical techniques, the researchers generated 3-D visualizations of the whales' internal anatomy, with both bones and soft tissue intact and in their undisturbed natural positions, providing "an unprecedented view of the internal anatomy of these animals," the scientists wrote.

Then the whale heads were dissected in the necropsy facility at the Marine Mammal Center at WHOI. Together, the studies showed that all the minke whales had "a large, well-formed fat body" connecting to the ears, providing a potential transmission pathway guiding sound from the environment to their inner ears.

"This is the first successful study of intact baleen whale head anatomy with these advanced imaging techniques," said WHOI Senior Scientist Darlene Ketten, director of the CSI lab at WHOI and co-author on the paper. "It really is an important addition to our understanding of large whale head and auditory systems."

Also collaborating on the study were Julie Arruda and Scott Cramer at the CSI and Kathleen Moore of IFAW.

This research was funded by a National Science Foundation Graduate Research Fellowship, a WHOI Ocean Life Institute Graduate Fellowship, the Joint Industry Program, the Office of Naval Research, and the U.S. Navy.

The Woods Hole Oceanographic Institution is a private, non-profit organization on Cape Cod, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the oceans and their interaction with the Earth as a whole, and to communicate a basic understanding of the oceans' role in the changing global environment. For more information, please visit www.whoi.edu

The Woods Hole Oceanographic Institution


Related Baleen Whales Current Events and Baleen Whales News Articles


Passive Acoustic Monitoring Reveals Clues to Minke Whale Calling Behavior and Movements in the Gulf of Maine
Scientists using passive acoustic monitoring to track minke whales in the Northwest Atlantic have found clues in the individual calling behaviors and movements of this species.

Plankton make scents for seabirds and a cooler planet
The top predators of the Southern Ocean, far-ranging seabirds, are tied both to the health of the ocean ecosystem and to global climate regulation through a mutual relationship with phytoplankton, according to newly published work from the University of California, Davis.

Smithsonian scientists solve 'sudden death at sea' mystery
Mass strandings of whales have puzzled people since Aristotle. Modern-day strandings can be investigated and their causes, often human-related, identified.

Antarctic fjords are climate-sensitive hotspots of diversity in a rapidly warming region
Deep inside the dramatic subpolar fjords of Antarctica, researchers from the University of Hawai'i at Mānoa have discovered an unexpected abundance and diversity at the seafloor.

New genomic study provides a glimpse of how whales could adapt to ocean
In a paper published in Nature Genetics, researchers from Korea Institute of Ocean Science and Technology, Korea Genome Research Foundation, BGI, and other institutes presented the first high-depth minke whale genome and their new findings on how whales successfully adapted to ocean environment.

Research Confirms Bottom-Feeding Behavior of Humpback Whales
Humpback whales are known for the complexity of their feeding techniques, which include "trapping" krill and other prey within bubble nets they produce and gulping up to two-thirds their weight in prey-laden water.

Dwarf whale survived well into Ice Age
Research from New Zealand's University of Otago detailing the fossil of a dwarf baleen whale from Northern California reveals that it avoided extinction far longer than previously thought.

Scientists Use Marine Robots to Detect Endangered Whales
Two robots equipped with instruments designed to "listen" for the calls of baleen whales detected nine endangered North Atlantic right whales in the Gulf of Maine last month.

Whales' foraging strategies revealed by new technology
Marine biologists are beginning to understand the varied diving and foraging strategies of filter-feeding whales by analyzing data from multisensor tags attached to the animals with suction cups.

NOAA: Underwater noise decreases whale communications in Stellwagen Bank sanctuary
According to a NOAA-led paper published today in the journal Conservation Biology, high levels of background noise, mainly due to ships, have reduced the ability of critically endangered North Atlantic right whales to communicate with each other by about two-thirds.
More Baleen Whales Current Events and Baleen Whales News Articles

War of the Whales: A True Story

War of the Whales: A True Story
by Joshua Horwitz (Author)


Two men face off against an all-powerful navy—and the fate of the ocean’s most majestic creatures hangs in the balance.

"A gripping, brilliantly told tale of the secret and deadly struggle between American national security and the kings of the oceans."—Bob Woodward

War of the Whales is the gripping tale of a crusading attorney who stumbles on one of the US Navy’s best-kept secrets: a submarine detection system that floods entire ocean basins with high-intensity sound—and drives whales onto beaches. As Joel Reynolds launches a legal fight to expose and challenge the Navy program, marine biologist Ken Balcomb witnesses a mysterious mass stranding of whales near his research station in the Bahamas. Investigating this calamity, Balcomb is forced to choose between his...

Handbook of Marine Mammals, Vol. 3: The Sirenians and Baleen Whales

Handbook of Marine Mammals, Vol. 3: The Sirenians and Baleen Whales
by Sam H. Ridgway (Editor)


From the back cover: Interest in marine mammals has increased greatly in recent years as our knowledge of them has grown. In particular, the large cetacean brain and the supposed superior intelligence of marine mammals over other animals, in conjunction with their obvious diving and swimming abilities, have made them fascinating creatures to study. Public involvement in the effort to conserve them from hunting by man and newly discovered ways of catching and maintaining them in captivity have all helped to increase their popularity and importance. In some cases this has resulted in the establishment of codes of practice for their capture, harvesting and transportation and has improved their lot from being mere objects of curiosity and participants in circus acts. However, the natural...

Whales, Dolphins and Porpoises

Whales, Dolphins and Porpoises
by Mark Carwardine (Author)


The perfect introductory guide to 96 species of whale, dolphin and porpoise that you are likely to spot on your whale-watching trip. More than 4.3 million people went on whale-watching excursions in 1998, and the number has been rising steadily since, signifying a growing global appreciation of these magnificent mammals and their environments. This pocket-sized guide is the ideal companion for whale-watching trips throughout the world, helping you to identify each species and discover more about them. It includes a detailed description and the ID Fact File provides at-a-glance information for each entry. Each species is illustrated with a stunning photograph, depicted as encountered on observation trips. It includes information on size, geographical distribution and diet. It also contains...

Baleen Whales (Read All about Whales)

Baleen Whales (Read All about Whales)
by Jason Cooper (Author)


Describes several different kinds of baleen whales, which have jaws lined with plates of baleen instead of teeth.

The Whale and the Supercomputer: On the Northern Front of Climate Change

The Whale and the Supercomputer: On the Northern Front of Climate Change
by Charles Wohlforth (Author)


Scientists and natives wrestle with our changing climate in the land where it has hit first
--and hardest

A traditional Eskimo whale-hunting party races to shore near Barrow, Alaska-their comrades trapped on a floe drifting out to sea-as ice that should be solid this time of year gives way. Elsewhere, a team of scientists transverses the tundra, sleeping in tents, surviving on frozen chocolate, and measuring the snow every ten kilometers in a quest to understand the effects of albedo, the snow's reflective ability to cool the earth beneath it.

Climate change isn't an abstraction in the far North. It is a reality that has already dramatically altered daily life, especially that of the native peoples who still live largely off the land and sea. Because nature shows her...

DK Eyewitness Books: Whale

DK Eyewitness Books: Whale
by Vassili Papastavrou (Author)


New Look! Relaunched with new jackets and 8 pages of new text!

Here is a spectacular and informative guide to whales, dolphins, seals, and manatees. Superb color photographs of dolphins, killer whales, walruses, and more offer a unique "eyewitness" view of these mysterious sea creatures - what they look like, how they behave, and their battle for survival. See the whiskers of a walrus, inside the mouth of a killer whale, dolphins at play, male elephant seals fighting, the way a blowhole works, a carved sperm whale's tooth, and a 19th-century blubber pot. Learn how deep a sperm whale can dive, how whales use bubbles to catch fish, why sea lions bark like dogs, what baleen is used for, and why killer whales come up on the beach. Discover how humpback whales communicate, why...

The Whale: In Search of the Giants of the Sea

The Whale: In Search of the Giants of the Sea
by Philip Hoare (Author)


“Unpredictable and amusing and informative and original, cavorting between biology, history, travel writing, and memoir.”—Mark Kurlansky The Whale by Philip Hoare is a enthralling and eye-opening literary leviathan swimming in similar bestselling waters as Cod and The Secret Life of Lobsters. Winner of the BBC Samuel Johnson Prize for Nonfiction, The Whale is a lively travelogue through the history, literature, and lore of the king of the sea—the remarkable mammals that we human beings have long been fascinated with, from Moby Dick to Free Willy. Bestselling author and naturalist Bernd Heinrich calls it, “a moving and extraordinary book,” and Hoare’s sparkling account of swimming with these incredible behemoths will delight whale and wildlife aficionados, lovers of the sea...

Beautiful Whale

Beautiful Whale
by Bryant Austin (Author), Sylvia A. Earle (Introduction)


Photographer and conservationist Bryant Austin's breathtaking photographic project Beautiful Whale is the first of its kind: It chronicles his fearless attempts to reach out to whales as fellow sentient beings. Featuring Austin's intimate images--some as detailed as a single haunting eye--that result from encounters based on mutual trust, Beautiful Whale captures the grace and intelligence of these magnificent creatures. Austin spent days at a time submerged, motionless, in the waters of remote calving grounds waiting for humpback, sperm, and minke whales to seek him out. As oceanographer Sylvia A. Earle says in her foreword to the book, "As an ambassador from the ocean--and to the ocean--Bryant Austin is not only a source of inspiration. He is cause for hope."

The Moon by Whale Light: And Other Adventures Among Bats, Penguins, Crocodilians, and Whales

The Moon by Whale Light: And Other Adventures Among Bats, Penguins, Crocodilians, and Whales
by Diane Ackerman (Author)


In a rare blend of scientific fact and poetic truth, the acclaimed author of A Natural History of the Senses explores the activities of whales, penguins, bats, and crocodilians, plunging headlong into nature and coming up with highly entertaining treasures.

Listening to Whales: What the Orcas Have Taught Us

Listening to Whales: What the Orcas Have Taught Us
by Alexandra Morton (Author)


In Listening to Whales, Alexandra Morton shares spellbinding stories about her career in whale and dolphin research and what she has learned from and about these magnificent mammals. In the late 1970s, while working at Marineland in California, Alexandra pioneered the recording of orca sounds by dropping a hydrophone into the tank of two killer whales. She recorded the varied language of mating, childbirth, and even grief after the birth of a stillborn calf. At the same time she made the startling observation that the whales were inventing wonderful synchronized movements, a behavior that was soon recognized as a defining characteristic of orca society.

In 1984, Alexandra moved to a remote bay in British Columbia to continue her research with wild orcas. Her recordings of the...

© 2014 BrightSurf.com