The human hand has around 29 major and small bones. This is not a universal number; many people have more bones than others.
Only 10 to 15% of all human beings are left-handed. One in 100 people are ambidextrous. This means that they can use both their hands equally.
The hands contain 29 major joints, at most 123 ligaments and 34 muscles. There are also 48 nerves and 30 blood vessels.
Nine muscles control the thumb, while three major hand nerves control it.
The fingers do not have muscles. Instead, the muscles that bend fingers are found in the palm and middle of the forearm. They are connected to the fingers via tendons.
One-quarter of the brain’s motor cortex is dedicated to the movement of the hand muscles.
Only primates can use their hands. There are 300 primate species, including humans, monkeys, apes, monkeys, and prosimians (lemurs lorises, tarsiers, and lorises).
Human hands can grasp things that primates like gorillas and chimps cannot. Because we have longer hands and stronger thumbs than our primate cousins, this is possible.
Touch can increase the production of oxytocin. This “feel good” hormone is released during bonding activities.
Holding hands can reduce cortisol levels, which is a stress hormone.
