Fingerprints, Snowflakes, and Other Patterns That Are Always Unique

Fingerprints

Fingerprints are the quintessential example of a unique natural pattern. Formed during fetal development, these intricate ridges and whorls result from a combination of genetic factors and developmental conditions. The complex interactions between genetic instructions and environmental influences (even down to the chemical environment inside the womb) create patterns so distinctive that even identical twins don’t have the same fingerprints. For this reason, fingerprints have been used to identify people for more than a century, especially in criminal investigations. The first criminal trial to use fingerprints as evidence was in 1910, and fingerprinting remains a vital part of forensic analysis. 

Snowflakes

Snowflakes are another naturally occurring phenomena that are famously distinctive. Snowflakes form when water vapor travels through the air and condenses on a particle, creating a slow-growing ice crystal. They can start off quite similar to each other, but nearly imperceptible changes in temperature and the amount of water in the air change how the molecules act and how they condense. Because of this, no matter how many billions of snowflakes fall from the sky, no two will ever be the same. 

Certain Animal Coat Patterns

Some animals possess unique markings that are genetically influenced but randomly distributed, serving to distinguish one animal of a certain species from another. Zebras, for example, may look very similar at first glance, but no two zebra stripe patterns are exactly alike. Scientists believe zebra stripes may have the social purpose of allowing the animals to recognize each other, while also possibly confusing predators such as lions and perhaps even helping regulate body temperature. Other animals with unique coat patterns include giraffes, tigers, and leopards. Their coats are the equivalent of human fingerprints, helping scientists identify individual animals simply by  their unique patterns. 

Humpback Whale Flukes

Scientists have recently discovered that unique marks on the underside of humpback whale flukes — the flat, horizontal lobes that make up each side of their tales — are useful identifiers just like human fingerprints. Each whale tail has unique patterns and coloration, which has proved invaluable to researchers, who can identify the animals by looking at the fluke when it rises above the water (which happens almost every time a whale starts to dive). Unique scarring and even barnacle distribution on the whale’s tail can make the identification process even easier. 

Blood Vessel Networks

The intricate network of blood vessels in human and animal bodies alike develops in a singular manner for each individual, making these networks as unique as fingerprints. In humans, vascular pattern recognition, also known as vein pattern authentication, is a fairly new form of biometric identification. It uses near-infrared light to scan the patterns of subcutaneous blood vessels in a hand or finger, verifying the identity of the scanned individual. The uniqueness of blood vessel networks has also been used to distinguish between individual animals. Rodents, for example, can be identified through the distinct blood vessel patterns of their ears, providing a quick, noninvasive, and painless way of telling these diminutive creatures apart. 

Eye Structures

The eyes, so they say, are the windows to the soul. As it happens, eyes are indeed unique identifiers in humans and other animals. Retinal scanning as a form of identification has been a staple of science fiction for decades but has also been utilized for security purposes in real life by government agencies including the FBI, CIA, and NASA. This form of identification works due to the aforementioned unique blood vessel patterns, which can be seen on a person’s retina. In fact, the retina is the only part of the human body where blood vessels can be viewed directly, without the need for an additional apparatus.

Our eyes offer another easy means of identification: the iris. The intricate arrangements of pigments and strands in an iris create a pattern so unique that it, too, can be used as a reliable biometric identification method. Iris recognition made the news in 2016 when it was revealed that the FBI had collected nearly 430,000 iris scans from people who’d been arrested — a highly controversial move, but one that clearly demonstrates the potential and efficacy of iris scanning for identifying humans.