Ponytail

A ponytail is a versatile hairstyle where some, most, or all of the hair is pulled away from the face. The hair is gathered and secured at the back of the head using a hair tie, a clip, or another accessory. Once secured, the hair is allowed to hang freely from that point.

The name comes from how the hair resembles the tail of a pony. This style is highly adaptable for various looks and functions. It can be worn at the middle of the back of the head or the base of the neck. Some people wear it on the side of the head, which is sometimes considered formal, or at the very top of the head.

There are several ways to divide and style hair in this manner. If the hair is divided into two separate sections, they are called pigtails, twintails, or bunches if they are left loose. If those two sections are plaited, they are called plaits or braids. The placement and method of securing the hair change the overall appearance. For example, a high ponytail might look different from a low ponytail. These variations allow the hairstyle to suit many different personal styles and social settings.

The history of the ponytail reaches back to Ancient Greece. Records from ancient Greek artefacts and artworks show women wearing this style. This includes frescoes painted in Crete between 2000 and 1500 BC. It is likely the hairstyle emerged in Greece before spreading to other regions. Egyptian and Roman art also depict women wearing styles we would call ponytails today. In European culture, it was unusual for adult women to wear ponytails in public until the mid-20th century.

Men have also used similar styles throughout history. In Europe, between 1751 and 1800, many men wore long hair tied with a ribbon. This was called a queue, which is the French word for "tail." While civilians eventually stopped wearing it, European armies used it as a mandatory style until the early 19th century. In Asia, the queue was a specific hairstyle for the Manchu people. From 1645 until 1910, the Qing dynasty required Han Chinese men to wear a waist-length pigtail. This was a symbol of dominance used to force submission. To wear the queue, men shaved the front and sides of their heads. This prevented them from styling their hair according to their own culture. Those who refused to wear it faced execution by beheading, though monks were an exception.

The ponytail serves many practical purposes in modern life. It is a common choice for exercising or working in environments like laboratories, hospitals, or wood shops. In these settings, tying hair up is often necessary for safety. It keeps hair out of the eyes during many different hobbies and jobs. For school-aged girls, the ponytail is popular because of its simplicity. A young girl can easily redo her own hair after a sports class. Many also use a scrunchie, which is a soft hair tie. Scrunchies are often seen as being better for hair health than traditional ties.

Scientists have even used mathematics to study the physics of a ponytail. Researchers in the UK developed a mathematical model to predict a ponytail's shape. This model considers the length and the random curvature, or curliness, of individual hairs. They created the Ponytail Shape Equation to understand how hairs interact. This equation relates elasticity, gravity, and orientational disorder. A key part of this is the Rapunzel number, which is a ratio used to calculate gravity's effect. A low Rapunzel number means the hair fans outward like a springy shape. A high Rapunzel number means gravity overwhelms the springiness, causing the hair to hang vertically.

This scientific research has real-world applications in the computer graphics and animation industries. The math helps animators create realistic digital hair and movement. Researchers also studied how a ponytail moves when a person is jogging. They found that an up-and-down motion is too unstable. Instead, any slight jostling causes the ponytail to sway from side to side. While the ponytail is a useful tool, users must be careful of health issues. Tying hair too tightly can cause traction alopecia, which is a form of hair loss. It can also lead to extracranial headaches caused by tension on the scalp nerves.