July 10, 2014

Why do we yawn?

If you just Googled the question, "Why do we yawn?" then you are not alone. For ages, people have wondered why we yawn and why yawns seem to be contagious. Perhaps someone sitting nearby just yawned, then you yawned as well...what's going on?
Photo by Sira Anamwong

For a long time, yawning was explained away as a quick way to get a shot of oxygen into your brain to keep you from falling asleep at your desk. However, some new research reveals that to be incorrect. According to Dr. Steven Platek of Georgia Gwinnett College, there is no evidence that yawning affects levels of oxygen in the bloodstream, blood pressure, or heart rate. It follows that yawning doesn't actually wake us up when we are sleepy or bored.

Instead, yawning might serve as a radiator to help cool the brain. According to Smithsonian,
Yawning—a stretching of the jaw, gaping of the mouth and long deep inhalation, followed by a shallow exhalation—may serve as a thermoregulatory mechanism, says Andrew Gallup, a psychology professor at SUNY College at Oneonta. In other words, it’s kind of like a radiator. In a 2007 study, Gallup found that holding hot or cold packs to the forehead influenced how often people yawned when they saw videos of others doing it. When participants held a warm pack to their forehead, they yawned 41 percent of the time. When they held a cold pack, the incidence of yawning dropped to 9 percent.
Most vertebrate animals yawn. In humans, the brain uses about 40% of the body's metabolic energy. That causes it to heat up like the engine of a race car, so there is support for the new theory that yawning helps to cool down the brain.

We still don't know exactly why yawns are contagious, but scientists are speculating that it is a social mirroring behavior. Mirroring is important among social animals. It's a result of us empathizing with each other.

July 1, 2014

Research shows whale feces could boost fisheries

Far from being a threat to fisheries, new research suggests whales may in fact play a key role in sustaining fish stocks by fertilizing ocean feeding grounds with their feces.
Photo provided by Blue Whale Study, Inc.

The research paper, titled Whales sustain fisheries: Blue whales stimulate primary production in the Southern Ocean, indicates the animals’ nutrient-rich defecations sustained fish stocks and promotes marine productivity in whale feeding grounds.

The study found that while whales do consume huge quantities of prey, they also pass a large proportion of the nutrients they consumed back into ocean surface waters, providing food for other prey fish.

Researcher Trish Lavery of Flinders University tells us that whether whales compete with fisheries for marine resources has been hotly debated.