How It Works

Top 5 Facts: Humans


While great apes such as gorillas, chimps and orangutans use facial expressions to show their feelings, human beings are the only animals to cry as a result of their emotions.

Sneeze fast!

A sneeze is typically expelled at around 161km/h (100mph). Sneezing helps protect the body by keeping the nose free of bacteria and viruses.

Red blood cells

Red blood cells – also known as erythrocytes – live on average for 120 days. There are approximately 2.5 trillion red blood cells in your body at any given moment.

Hard worker

The heart beats on average 100,000 times per day. Of course this will vary greatly depending on your level of activity and your environmental conditions.


Humans are made up of 70 per cent water, which is essential for body growth and repair. The NHS suggests drinking 1.2 litres of water a day to avoid growing dehydrated.

  • unmannedair

    A lot of this stuff is not forensics. Forensics borrowed a lot of this stuff from other fields. Carbon-14 analysis is physics, not forensics for example. Carbon-14 dating is only effective over semi-large ranges of time, and involve some pretty broad assumptions. This gives ranges of dates that the organism could have lived. This article reads like it was written after watching a Bones episode… Not accurate TV by the way.