Scientists Use a CT Scanner to Give Whales a Hearing Test

Ted Cranford
Ted Cranford

It's hard to study how whales hear. You can't just give the largest animals in the world a standard hearing test. But it's important to know, because noise pollution is a huge problem underwater. Loud sounds generated by human activity like shipping and drilling now permeate the ocean, subjecting animals like whales and dolphins to an unnatural din that interferes with their ability to sense and communicate.

New research presented at the 2018 Experimental Biology meeting in San Diego, California suggests that the answer lies in a CT scanner designed to image rockets. Scientists in San Diego recently used a CT scanner to scan an entire minke whale, allowing them to model how it and other whales hear.

Many whales rely on their hearing more than any other sense. Whales use sonar to detect the environment around them. Sound travels fast underwater and can carry across long distances, and it allows whales to sense both predators and potential prey over the vast territories these animals inhabit. It’s key to communicating with other whales, too.

A CT scan of two halves of a dead whale
Ted Cranford, San Diego State University

Human technology, meanwhile, has made the ocean a noisy place. The propellers and engines of commercial ships create chronic, low-frequency noise that’s within the hearing range of many marine species, including baleen whales like the minke. The oil and gas industry is a major contributor, not only because of offshore drilling, but due to seismic testing for potential drilling sites, which involves blasting air at the ocean floor and measuring the (loud) sound that comes back. Military sonar operations can also have a profound impact; so much so that several years ago, environmental groups filed lawsuits against the U.S. Navy over its sonar testing off the coasts of California and Hawaii. (The environmentalists won, but the new rules may not be much better.)

Using the CT scans and computer modeling, San Diego State University biologist Ted Cranford predicted the ranges of audible sounds for the fin whale and the minke. To do so, he and his team scanned the body of an 11-foot-long minke whale calf (euthanized after being stranded on a Maryland beach in 2012 and preserved) with a CT scanner built to detect flaws in solid-fuel rocket engines. Cranford and his colleague Peter Krysl had previously used the same technique to scan the heads of a Cuvier’s beaked whale and a sperm whale to generate computer simulations of their auditory systems [PDF].

To save time scanning the minke calf, Cranford and the team ended up cutting the whale in half and scanning both parts. Then they digitally reconstructed it for the purposes of the model.

The scans, which assessed tissue density and elasticity, helped them visualize how sound waves vibrate through the skull and soft tissue of a whale’s head. According to models created with that data, minke whales’ hearing is sensitive to a larger range of sound frequencies than previously thought. The whales are sensitive to higher frequencies beyond those of each other’s vocalizations, leading the researchers to believe that they may be trying to hear the higher-frequency sounds of orcas, one of their main predators. (Toothed whales and dolphins communicate at higher frequencies than baleen whales do.)

Knowing the exact frequencies whales can hear is an important part of figuring out just how much human-created noise pollution affects them. By some estimates, according to Cranford, the low-frequency noise underwater created by human activity has doubled every 10 years for the past half-century. "Understanding how various marine vertebrates receive and process low-frequency sound is crucial for assessing the potential impacts" of that noise, he said in a press statement.

Wayfair’s Fourth of July Clearance Sale Takes Up to 60 Percent Off Grills and Outdoor Furniture

Wayfair/Weber
Wayfair/Weber

This Fourth of July, Wayfair is making sure you can turn your backyard into an oasis while keeping your bank account intact with a clearance sale that features savings of up to 60 percent on essentials like chairs, hammocks, games, and grills. Take a look at some of the highlights below.

Outdoor Furniture

Brisbane bench from Wayfair
Brisbane/Wayfair

- Jericho 9-Foot Market Umbrella $92 (Save 15 percent)
- Woodstock Patio Chairs (Set of Two) $310 (Save 54 percent)
- Brisbane Wooden Storage Bench $243 (Save 62 percent)
- Kordell Nine-Piece Rattan Sectional Seating Group with Cushions $1800 (Save 27 percent)
- Nelsonville 12-Piece Multiple Chairs Seating Group $1860 (Save 56 percent)
- Collingswood Three-Piece Seating Group with Cushions $410 (Save 33 percent)

Grills and Accessories

Dyna-Glo electric smoker.
Dyna-Glo/Wayfair

- Spirit® II E-310 Gas Grill $479 (Save 17 percent)
- Portable Three-Burner Propane Gas Grill $104 (Save 20 percent)
- Digital Bluetooth Electric Smoker $224 (Save 25 percent)
- Cuisinart Grilling Tool Set $38 (Save 5 percent)

Outdoor games

American flag cornhole game.
GoSports

- American Flag Cornhole Board $57 (Save 19 percent)
- Giant Four in a Row Game $30 (Save 6 percent)
- Giant Jenga Game $119 (Save 30 percent)

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How the Scientist Who Invented Ibuprofen Accidentally Discovered It Was Great for Hangovers

This man had too many dry martinis at a business lunch.
This man had too many dry martinis at a business lunch.
George Marks/Retrofile/Getty Images

When British pharmacologist Stewart Adams and his colleague John Nicholson began tinkering with various drug compounds in the 1950s, they were hoping to come up with a cure for rheumatoid arthritis—something with the anti-inflammatory effects of aspirin, but without the risk of allergic reaction or internal bleeding.

Though they never exactly cured rheumatoid arthritis, they did succeed in developing a nonsteroidal anti-inflammatory drug (NSAID) that greatly reduced pain of all kinds. In 1966, they patented their creation, which was first known as 2-(4-isobutylphenyl) propionic acid and later renamed ibuprofen. While originally approved as a prescription drug in the UK, it soon became clear ibuprofen was safer and more effective than other pain relievers. It eventually hit the market as an over-the-counter medication.

During that time, Adams conducted one last impromptu experiment with the drug, which took place far outside the lab and involved only a single participant: himself.

In 1971, Adams arrived in Moscow to speak at a pharmacology conference and spent the night before his scheduled appearance tossing back shots of vodka at a reception with the other attendees. When he awoke the next morning, he was greeted with a hammering headache. So, as Smithsonian.com reports, Adams tossed back 600 milligrams of ibuprofen.

“That was testing the drug in anger, if you like,” Adams told The Telegraph in 2007. “But I hoped it really could work magic.”

As anyone who has ever been in that situation can probably predict, the ibuprofen did work magic on Adams’s hangover. After that, according to The Washington Post, the pharmaceutical company Adams worked for began promoting the drug as a general painkiller, and people started to stumble upon its use as a miracle hangover cure.

“It's funny now,” Adams told The Telegraph. “But over the years so many people have told me that ibuprofen really works for them, and did I know it was so good for hangovers? Of course, I had to admit I did.”

[h/t Smithsonian.com]