Our project purpose. During weeks 10 through 24 of gestation, ridges are formed on the epidermis, which is the outermost layer of skin, on your fingertips. The pattern that these ridges make is known as your fingerprint. Fingerprints are static and do not change with age, so an individual will have the same fingerprint from infancy to adulthood. The pattern changes size, but not shape, as the person grows. (To get a better idea of how that works, you can model the change in size by inking your fingerprint onto a balloon and then blowing up the balloon.) Since each person has unique fingerprints that do not change over time, they can be used for identification. For example, police use fingerprints to determine whether a particular individual has been at a crime scene. Although the exact number, shape, and spacing of the ridges changes from person to person, fingerprints can be sorted into three general categories based on their pattern type: loop, arch, and whorl.The DNA they inherit from their parents determines many other personal characteristics and traits, like whether someone is right- or left-handed or the color of their eyes. In this project you'll examine fingerprints from siblings versus pairs of unrelated individuals to figure out if general fingerprint patterns are genetic or random.Have you ever looked at two girls and said, "you must be sisters"? We can often tell that two people are siblings because they appear to have several similar physical traits. This is because children receive half their DNA from each parent. All biological siblings are the mixture of both parents' DNA. This results in a greater degree of matching traits between siblings than between unrelated individuals. Therefore, if DNA determines fingerprint patterns, then siblings are more likely to share the same fingerprint category than two unrelated individuals are.