Fingerprints

By Esha Khakha Year 7

I will be writing about how we are all unique based on our fingerprints. I was inspired to write about this because ever since I was quite small, I always wondered, “How are we all different if our fingerprints all look the same?” I put some research into it to solve the question I was thinking about and here’s what I found.

What is a fingerprint?

Fingerprints are impressions left on surfaces by the friction ridges on the finger of a person. Our fingerprint’s lines are made up of friction ridges (friction is the action of rubbing against a surface or object) ridges. Friction ridges are a raised portion of the epidermis, caused by the underlying interface between the dermal papillae of the dermis and interpapillary parts of the epidermis. Here is a diagram to explain how this works:

Nobody really noticed the fingerprints and scientists assumed it was just a form of birth mark. In 1788, a German anatomist-the study of natural organisms and living things-called Johann Christoph Andreas Mayer was the first to find out every human had an original fingerprint. Not much, unfortunately, is known about how he discovered this, but we do know he did carry out surveys, and other scientists plagiarised from him that many people have solid lines in their fingerprints that others may have, but other tiny lines that aren’t on others’ fingers.

How did we each develop unique fingerprints?

After a foetus is 17 weeks old, a baby’s surface layers of their skin begin to fold and, due to friction “ridges” , their fingerprint is set. Many people query that identical twins mean identical fingerprints, but that is not the case. So, although their shared DNA means their fingerprints look similar, they really aren’t, because a baby who’s in the womb with another baby will experience different sensations, i.e. one baby might experience more pain since they’re located on a different side to the other, changing the friction and the fingerprint. This same fingerprint will stay with us through life, and if it disappears due to cuts, it will immediately come back exactly the same.

The benefits of unique fingerprints

There are many benefits, but the main use of them is that they can help keep us safe. Since nobody has the same fingerprint(but the possibility of 2 people having the same is 1 in 64 billion according to sciencefocus.com) police officers can identify criminals by examining something they have touched with their fingers. Then the police use a brush to wipe away any dust and reveal a faint fingerprint. They then stick the faint fingerprint onto adhesive sticky sheets keeping it preserved and send it off to a laboratory and work out who the criminal was.

Sources

● BBC Science Focus Magazine. (n.d.). Why do identical twins have different fingerprints? [online] Available at: sciencefocus.com/the-human-body/why-do-identical-twins-have-different-fingerprints-2/#:~:text=Even%20identical %20twins%20%E2%80%93%20who%20have [Accessed 10 Feb. 2022]. ● Wikipedia Contributors (2019). Fingerprint. [online] Wikipedia. Available at: en.wikipedia.org/wiki/Fingerprint