That blast of air you get when entering stores is used to keep insects out!

They’re called air doors or air curtains. These devices have powerful fans that can blast air all the way to the floor. They have many uses, although their first use was to keep flying insects out of buildings by creating forceful turbulence.

Nowadays, air curtains also have air heaters or coolers, and they serve as a way to keep cold air from escaping in the summer or coming in during the winter. This saves a lot of energy because it reduces heat transfer between two spaces. However, a closed door is still much more effective.

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Women speak in a higher pitch to men they find attractive!

After a research paper was published that asserted men are more attracted with women with higher pitched voices, a group of researchers tried to prove the flipside of that: Do women use a higher pitch when they talk to men they are attracted to?

They showed women a series of photos of men that had either more masculine or more feminine faces and express which faces they preferred. They also asked them to record a message that said: ‘Hi, we met at a bar last night. I was just calling you to see if you wanted to go out sometime. Call me back,’ after showing them either a masculinized or feminized face of a man.

What they found was that women who preferred more masculine faces would use a higher pitch to record a message after being shown a masculine face, and women who preferred feminine faces would also use a higher pitch after seeing a more feminine face.

Their conclusion was that voice pitch serves as a sexual signal and women tend to use a higher pitch when talking to someone they’re attracted to!

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When contestants leave Hell's Kitchen, they're sent to a psychiatrist to make sure they don't have suicidal thoughts!

It seems like Hell’s Kitchen lives up to it's name both on and off screen. Contestants on Gordon Ramsay’s show live such tough lives during the a season’s shooting that they are sent for a psychiatric evaluation after the show is done.

They’re also sent to a ‘beautiful house’ that is basically a spa: You get back rubs, eat and get pampered. Some contestants call it decompression before you go back into society. The show can be so stressful that Gordon Ramsey even has bodyguards on set to prevent incidents.

Among the things contestants are required to do is disconnect from the outside world. Computers, personal electronics, phones or even newspapers are not allowed while the show is being filmed. The show isn’t filmed in an actual restaurant, but rather a set where every single corner of the dining area and the kitchen is being filmed.

Read more about this show at the source.

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A Leopard seal once tried to teach a photographer how to hunt!

Leopard seals are second only to killer whales in the power rankings of Antarctica’s top predators. Their mouth is wider than a grizzly bears’ and it’s canine teeth can measure up to 1 inch in length.

They are mostly solitary creatures and come together in groups only during mating season. They’ve also been described as bold, powerful and curious. They’ve been known to play with penguins that they do not intend to eat.

A photographer for National Geographic once went on a photography expedition and had a very curious encounter with a leopard seal. It started bringing live penguins to him; then injured ones and finally dead penguins. The seal was trying to teach him how to hunt!

Check out the video below to hear his account in more detail.

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Wheel guards are actually not the reason why trains stay on the tracks!

It is actually all because of the weight of the train, the angle of the wheels, and gravity! Railway wheels simply sit on the tracks and the projection of the train pushes them forward.

When there is a curvature in the track or a turn, the train doesn’t change direction because it hits a guard rail, or a flange, but rather because of the force of the train and the slight angle of the wheels. The wheels are angled slightly inward so that when the track angles to the right the outer wheel has a greater distance to travel than the inner wheel, resulting in a turn.

So why are there guards? These are actually just a last resort in case the train happens to derail. Fortunately, gravity and a slight angle usually do the trick just fine!

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