Scientists have several ideas why humans can high-five each other instead of, say, high four or high six. One theory suggests four fingers and a thumb on each hand are the perfect number and length to grip objects firmly. (Another study suggests we can gasp most things with just our thumb and index finger if necessary ; the other four fingers are spares).
The process of evolution determined the most beneficial number of fingers and toes for our survival. Pandas, after all, have thumblike digits to help them grasp bamboo shoots, while some birds have quadruple digits for perching and tucking away during flight. Occasionally, babies are born with extra fingers and toes (a condition known as polydactyly), but those additional digits have never offered enough of an edge to survive to later generations. In other words, evolution determined that five fingers per hand are just right for humans.
Why do we have thumbs?
Having no thumbs would make you all thumbs, fumbling to tie your shoes or assemble a hamburger. (Don’t believe us? Tape one of your thumbs against the side of your hand and see how hard life becomes). We inherited a fully “opposable” thumb named for its ability to close tip-to-tip against our other fingers – grom our primate ancestors around two million years ago. These ancient relatives needed handier hands to help get a grip on simple tools. So give a thumbs – up to your thumbs. So give a thumbs – up to your thumbs. They are the main reasons you can text with one hand and build a burger without fumbling the bun.
Do other animals have thumbs beside us?
Lots of them, although the exact number depends on your definition of “thumbs”. Apes and many monkeys have opposable thumbs just like us, while smaller primates, pandas, and koalas have thumblike digits and claws that help them grip plants and prey.
Why do we have fingerprints?
Those whirls, swirls, loops, and arches on your fingertips (and toes, in case you didn’t know) are hnique to you – even if you have an identical twin – and they remain unchanged throughout your entire life. In fact, the faint ridges known as fingerprints form before you have ever born. Fluids in the womb put pressure on your developing digits, which, combined with your rate of growth and genetic makeup, create one-of-a-kind designs.
Okay, but why do we have fingerprints?
Ah, you want to know the point of those fingertip designs ( well, besides incriminating crooks who forget to wear gloves). Scientist have put forth all sorts of possible reasons. Fingerprints might magnify the hand’s ability to detect vibrations, for example, or improve our sense of touch. They also might work like tyre trying to help They also might work like tire treads to help us grip objects.
Why do my fingers wrinkle when we’ve been swimming?
You might think that playing in the pool or soaking in the tub makes your fingertips and toes waterlogged and soggy. Not so ! The prune effect is caused by blood vessels bringing just below the skin – an automatic reaction triggered by your nervous system when it senses long exposure to water. Scientists think people evolved this reaction to improve their grip and traction in wet environments. After all, pruny fingers make it easier to snag slippery fish.
Why can we pop our knuckles?
When you move or bend your fingers, you occasionally squeeze tiny air bubbles that form in the protective fluid around your body’s joints.Those poping bubbles create an audible crack.
WHY? – Answers to everything, Image publications.