Fewer than 20% of all sharks are larger than adult humans.

In addition, half of all the 400 different species of shark never grow beyond 6 feet long, which is about the size of an average adult human male. Now some of you are surely asking, “but how scary are the members of that original 20%...?”

Fear not! The three largest sharks (and three largest fish in the sea for that matter) are the whale shark, the basking shark, and the megamouth – all of which are completely harmless to humans!
(source)

The hair of Pittsburgh Steelers safety Troy Polamalu has been insured for a million dollars.

Due to the notoriety Troy has gained from both his stellar play and his flowing mane, Head and Shoulders shampoo has chosen him as their extremely qualified spokesperson. In order to protect this investment, the company actually took out a million dollar insurance policy on his mop!

Having grown it out as a tribute to his Samoan heritage, Polamalu claims that he hasn’t received a haircut in nearly 8 years! This seems reasonable, considering his luscious black locks are now nearly 3 feet long.

As for the disadvantages? In 2006 Polamalu was tackled by the Chiefs’ Larry Johnson by his hair during a 49-yard interception return.



(source)

The smallest monkey in the world is only about 15 cm tall.

Native to the rainforests of northern South America, the pygmy marmoset tops out at an adult weight of approximately 4 ounces! They typically reside in social groups of about 15 members, which consist of a mating couple and all their offspring.

They defend their home area of less than an acre through calling, chasing, and exposing their distinct white genitals.
(Sources: 1, 2)

Tipping is not allowed in Iceland.

The reason for this is that service charges are included on all transactions in this country. Interestingly, discussing the weather there is also considered to be in bad form.

Another matter of social etiquette is that Icelanders typically do not set appointments or stress punctuality – most residents have a fairly “open door” policy.
(source)

Do you know if you are a ‘morning person’? Your hair does...

Scientists recently discovered that the genes responsible for regulating our sleep cycles can be found in several of the body’s RNA strands, or chains of molecules that make up proteins. A small section of your brain called the ‘suprachiasmatic nucleus sends out signals that are processed in 24-hour cycles by RNA strands throughout the body.

The easiest RNA strands for scientists to test are located in the cells of your hair follicles. Their results showed that the human brain “turns on” these body clock genes at different times of the morning for different people.

However, this activation occurs at a consistent time for each individual, therefore making it possible to separate the early birds from the late risers on a genetic level.
(source)

The length of your foot is the same as the length of your forearm.

You know what they say about big feet? Big...forearms.

Go head and measure! From heel to toe should be the same as from elbow to wrist. The study of these ratios in body sizing is called anthropometry. This science has been extremely useful over the years in such areas as clothing design, forensics, and studies of human migration patterns over time.

Shoe size is also a pretty good indicator of height. However, foot length correlates with height more with men. For women, it's easier to estimate height based on foot width.
(source)