Fingerprinting
Students take their fingerprints and identify the patterns.
What You Need
- One pencil (per child)
- Clear tape enough to share
- Hand printout or blank paper (one per child)
- Fingerprint patterns handout (enough to share or one per child)
Attachments
Fingerprinting - Do identical twins have the same fingerprint
Safety Notes
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What To Do
- If you only have blank paper, have each child trace their hand out.
- With the pencil, generously cover in a 3cm by 3cm square on the paper.
- Rub fingertip on the penciled in square until it's covered with dust.
- Place clear tape on finger tip, on top of dust.
- Remove tape and place it on corresponding fingertip on the hand schematic.
- Identify what kind of fingerprint it is based on the fingerprinting chart.
Discovery
Do identical twins have the same fingerprints?
Fingerprints are not an entirely genetic characteristic. Scientists love to use this topic as an example of the old "nature vs. nurture" debate. Fingerprinting, along with other physical characteristics, is an example of a phenotype -- meaning that it is determined by the interaction of an individual's genes and the developmental environment in the uterus.
The ultimate shape of fingerprints are believed to be influenced by environmental factors during pregnancy, like nutrition, blood pressure, position in the womb and the growth rate of the fingers at the end of the first trimester. Thus, you will find similar patterns of whorls and ridges in the fingerprints of identical twins. But there will also be differences -- just as there are differences between the fingers on any individual's hands."
So the answer is NO.
Second, the mathematicians tell us that if the fetus had flattened finger pads, the baby is more likely to have the simpler arch pattern, or the slightly more complicated loop pattern. But on the other hand, if the fetus had swollen finger pads, baby is more likely to have the more complex whorl pattern of ridges. The two identical twins might grow in the same uterus, but they have different lengths and diameters of umbilical cord, so they will each get a different blood flow. The twin with the lesser blood flow will cut down the blood flow to the lower body, to preserve it for the brain. By an accident of anatomy, this gives more blood flowing into the arms. The baby ends up with proportionately bigger fingers, and more whorls in their fingerprints.
In 2003, a paper called On the similarity of identical twin fingerprints was published in The Journal of the Pattern Recognition Society. They found that the fingerprints of 94 "identical" twins were not identical - although they were more similar than non-related people.
Investigate Further
Do identical twins have the same fingerprints?
Fingerprints are not an entirely genetic characteristic. Scientists love to use this topic as an example of the old "nature vs. nurture" debate. Fingerprinting, along with other physical characteristics, is an example of a phenotype -- meaning that it is determined by the interaction of an individual's genes and the developmental environment in the uterus.
The ultimate shape of fingerprints are believed to be influenced by environmental factors during pregnancy, like nutrition, blood pressure, position in the womb and the growth rate of the fingers at the end of the first trimester. Thus, you will find similar patterns of whorls and ridges in the fingerprints of identical twins. But there will also be differences -- just as there are differences between the fingers on any individual's hands."
So the answer is NO.
Second, the mathematicians tell us that if the fetus had flattened finger pads, the baby is more likely to have the simpler arch pattern, or the slightly more complicated loop pattern. But on the other hand, if the fetus had swollen finger pads, baby is more likely to have the more complex whorl pattern of ridges. The two identical twins might grow in the same uterus, but they have different lengths and diameters of umbilical cord, so they will each get a different blood flow. The twin with the lesser blood flow will cut down the blood flow to the lower body, to preserve it for the brain. By an accident of anatomy, this gives more blood flowing into the arms. The baby ends up with proportionately bigger fingers, and more whorls in their fingerprints.
In 2003, a paper called On the similarity of identical twin fingerprints was published in The Journal of the Pattern Recognition Society. They found that the fingerprints of 94 "identical" twins were not identical - although they were more similar than non-related people.