Scientists says many ideas behind that. One theory suggest that four fingers and one thumb on each hand are the perfect number and length to grip object firmly. (another study suggests we can grasp most thing with just our thumb and index finger is 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 than grasps bamboo shoots, while some birds have quadruple digits for perching and tucking away during flight. Occasionally, babies are born with extra fingers and toes (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 just right for us.
Why do I have thumbs?
Having no thumbs would make you all thumbs, fumbling to tie your shoes or assemble a hamburger. We inherited a fully "opposable" thumbs named for his ability to close tip to tip against our other fingers --from our primate ancestors around two million years ago. These ancient relatives needed handier hand to help get a grip on simple tools. So give a thumbs-up to your thumbs. Thay are the main reason you can text with one hand and build a burger without fumbling the bun.
Do other animals have thumbs besides us???
Lots of them, although the exact numbers depend 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 I have fingerprints ?????
Those whirls, swirls, loops, and arches on your fingertips (and toes, in case you didn't know) are unique to you. Even if have identical twim-and they remained unchanged throughout entire life. In fact, the fact ridges known as fingerprints from before even you are 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.
Why do my fingers wrinkle when I have 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 shrinking 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 enviorments. After all, print fingers make it easier to sang slippery fish.
Why can I pop my KNUCKLES????
When you move or bend your fingers, you occasionally squeeze tiny air bubbles that from in the protective fluid around your body's joint. Those popping bubbles create an audible crack.
The process of evolution determined the most beneficial number of fingers and toes for our survival. Pandas, after all have thumblike digits to help than grasps bamboo shoots, while some birds have quadruple digits for perching and tucking away during flight. Occasionally, babies are born with extra fingers and toes (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 just right for us.
Why do I have thumbs?
Having no thumbs would make you all thumbs, fumbling to tie your shoes or assemble a hamburger. We inherited a fully "opposable" thumbs named for his ability to close tip to tip against our other fingers --from our primate ancestors around two million years ago. These ancient relatives needed handier hand to help get a grip on simple tools. So give a thumbs-up to your thumbs. Thay are the main reason you can text with one hand and build a burger without fumbling the bun.
Do other animals have thumbs besides us???
Lots of them, although the exact numbers depend 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 I have fingerprints ?????
Those whirls, swirls, loops, and arches on your fingertips (and toes, in case you didn't know) are unique to you. Even if have identical twim-and they remained unchanged throughout entire life. In fact, the fact ridges known as fingerprints from before even you are 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.
Why do my fingers wrinkle when I have 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 shrinking 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 enviorments. After all, print fingers make it easier to sang slippery fish.
Why can I pop my KNUCKLES????
When you move or bend your fingers, you occasionally squeeze tiny air bubbles that from in the protective fluid around your body's joint. Those popping bubbles create an audible crack.
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