- There are very few animals with fingerprints as unique as ours, and these include chimpanzees and koalas
- Opposable thumbs evolved about 2.6 million years ago when humans began using stone tools more frequently
Have you ever thought about your hands? After millions of years of evolution, they have developed into a highly useful part of our anatomy. With our hands, we developed the first tools and learned to make fire and, today " capable of many tasks " our hands equip us for modern life.
The key player in the evolution of the human hand is the opposable thumb.
Sabrina Harrison, a research assistant to orthopaedic surgeon Dr Peter Jebson, who wrote Hand Secrets (1998), says that "without opposable thumbs, humans would not be able to handle tools that helped drive our species forward".
Harrison, who is student at Michigan State University College of Human Medicine, explains that opposable thumbs evolved about 2.6 million years ago when humans began using stone tools more frequently.
"Opposable" in this case means the thumb can be placed opposite the other fingers on the same hand, and touch each of them. Most primates have opposable thumbs, while some more surprising animals, such as the arboreal frog, koala and giant panda, also benefit from this useful digit.
Nonetheless, out of all these species, humans can reach their thumb the farthest across their hands. Our thumbs are so useful that during the Gallic Wars, a series of military campaigns waged by Julius Caesar against several Gallic tribes, Caesar made examples of captured soldiers by amputating their thumbs so they couldn't hold weapons.
How biomarkers are the secret to looking younger than you are
While the thumb is our most useful digit, our ring finger is considered the least useful.
If you place the knuckle of your middle finger and your remaining fingertips on a surface, you will find you cannot lift your ring finger. This is because of how its tendons are connected to the tendons of the middle finger.
Our fingers are a particularly interesting part of our anatomy as they do not have any muscles. Instead, they are moved by muscles in the palm and mid forearm which are connected to the fingers by tendons.
While the ring finger is the weakest, Harrison says it means it is also the most gentle, so "dermatologists recommend you use it to apply eye lotions and concealer".
The palm side of the hand is unique because it is one of the few areas of the body without any hair (along with our lips and the soles of our feet), and is usually unable to tan.
The palm side is also unique because of our fingerprints, as no two people in the world share the same prints. If you want to get technical, however, there is a one-in-64-billion chance that you will have the same fingerprints as another human being.
Fingerprinting is an ideal form of identification because prints are easy and inexpensive to collect, and do not change with age " or even death. There are very few animals with fingerprints as unique as ours, and these include chimpanzees and koalas. Koala's prints are in fact so similar to humans', that experts even struggle to distinguish the two.
Harrison says because we regularly use our hands, they are vulnerable to different problems, including carpal tunnel syndrome, Dupuytren's contracture, arthritis, fractures and tendinitis.
Harrison stresses that "since our hands are possibly the most used part of our body, it is incredibly important to keep them healthy".
From tools to texting, hands have played, and continue to play, an integral role in human evolution and development. The hands' 27 bones (and zero muscles) have seen the construction of some of the world's most marvellous creations: the Egyptian pyramids and Michelangelo's Sistine Chapel, to name a few.
To continue such hand-some hand-y work, we must look after this precious part of our body. Ladies and gentlemen, a round of applause for our wonderful hands … oh, wait " they're doing that, too.
Seven tips for happy, healthy hands
1. Wash your hands regularly to rid them of germs, and remember, don't forget to wash between the fingers.
2. Exfoliate the hands to remove dead skin cells, making them softer and healthier.
3. Keep your hands well moisturised, especially during winter months. Apply a moisturiser that contains hydrocortisone, as this heals damaged skin cells more rapidly. Dermatologists also recommend shea or cocoa butter lotions. Apply moisturiser five to six times a day.
Falls for elderly people can be serious. How to prevent them
4. Avoid dry hands by washing them in warm water and using a mild soap containing limited amounts of alcohol and parabens, wearing gloves when you're outside and using a humidifier at home.
5. Hand therapy treatments like paraffin dips, cold/hot packs and even electrical stimulation can help if your hands are stiffening because of age, diabetes or overuse.
6. Treat any cut or abrasion on the hand with an appropriate healing ointment and a bandage to encourage healing.
7. Enjoy the occasional manicure. However, take care when using sharp tools.
Copyright (c) 2019. South China Morning Post Publishers Ltd. All rights reserved.