Cockroaches have been around for more than 70 million years, but there are plenty of facts people don’t know about them. The Harrow Times takes a look at the top ten filthy facts about the pests.

1. They can eat ANYTHING
Cockroaches are able to eat virtually anything for food, including paper, glue, soap, leather, even hair. And of course a tasty Subway.

2. Decapitating them won’t stop them
A cockroach can live for weeks at a time even with its head cut off - decapitation is not enough to kill them.

3. There are some huge ones
The world's largest cockroach (which lives in South America) is six inches long with a one-foot wingspan, but your average cockroach can vary in size from half an inch to two inches long.

4. They’re EVERYWHERE
It is thought there are more than 4,000 species of cockroaches worldwide, including the most common species, the German cockroach. Only 40 of these species are known as pests to humans, however.

5. Cockroaches rely on water
Cockroaches can live without food for one month, but will only survive one week without water.

6. They would be incredibly fast if they were human sized
Roaches can run at around three miles per hour – but this would translate to around 200mph if they were the same size as humans.

7. Heads, shoulders, knees and toes
They have six legs, but also have eighteen knee joints.

8. Science has found they can be conditioned
Makoto Mizunami and his colleague Hidehiro Watanabe, both of Tohoku University, found cockroaches could be conditioned. They introduced the scent of vanilla or peppermint before giving the roaches a sugary treat, and eventually, the cockroaches would drool when their antennae detected one of these smells.

9. You will probably eat one today.
There are eight insect parts in an average chocolate bar, and cockroach contamination can occur when food is being grown.

10. They don’t like mornings
Scientists discovered that cockroaches are unable to form new memories until a few hours after they have woken up.