Shark skin doesn't look like normal fish skin. It's made of microscopic diamond shaped scales with rough edges, called "denticles". These are thought to share an evolutionary origin with teeth - indeed, they have much more in common with teeth than with scales. Like teeth, they consist of a central cavity made of pulp surrounded by dentine and enamel.

The flexible but irregular surface is impossible for barnacles and other micro-organisms to cling to, as well as decreasing drag and turbulence.

So just when you thought sharks couldn't get any scarier, it turns out that their entire bodies are literally COVERED with teeth. ...

The medication is designed to be injected right after a traumatic experience. It targets Oprl1, a receptor that researchers believe is responsible for attaching fear to traumatic memories.

Post-traumatic stress disorder is caused by many things, such as surviving an accident or exposure to violence. There are genetic risk factors, but many people who acquire the disorder had no predisposition. Symptoms include debilitating flashbacks and hallucinations of the event, avoiding close relationships, angry or violent outbursts, and an inability to return to the location where the traumatic experience occurred, among many others.

Roll cloud over Uruguay. This low, roll cloud formation occurs when sinking cold air causes warm, moist air on the planet's surface to climb to higher altitudes, where the moisture condenses into cloud form. Roll clouds aren't dangerous in themselves, though, and many roll clouds form in relatively calm weather as a result of sea breezes.

These are the first photos ever taken of the clearest lake in the world. In the water of Blue Lake in New Zealand's South Island you can see for around 76 metres - in distilled water you can see 80 metres.

Did you know there is an island floating in the Pacific Ocean made entirely of garbage?


The Great Pacific Garbage Patch is a collection of trash and debris in the North Pacific Ocean. The center of this region of water is very calm because it lies within a gyre. A gyre is a circulating current in the ocean formed by wind patterns and the Earth’s rotation. Garbage does not escape easily from this region, and the rotation of the water here tends to draw trash in. The majority of the debris is composed of small plastic pieces that may not be visible to the naked eye but also do not biodegrade. Similar areas also exist in the Atlantic Ocean. This phenomenon is well-documented in shallow ocean depths. Now, according to scientists at the Montere ...