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Author Topic: Why do we leave fingerprints?  (Read 4555 times)

PHILIP BOND

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Why do we leave fingerprints?
« on: 15/10/2011 16:30:02 »
PHILIP BOND asked the Naked Scientists:
   
Why do we leave fingerprints?

What do you think?
« Last Edit: 15/10/2011 16:30:02 by _system »


 

Offline Geezer

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Why do we leave fingerprints?
« Reply #1 on: 15/10/2011 16:39:18 »
So the rozzers can nab us?
 

Offline Airthumbs

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Why do we leave fingerprints?
« Reply #2 on: 15/10/2011 23:51:40 »
What exactly are fingerprints?  Without raising the question, Why do we have fingerprints, the answer might be that our fingers act a little like an ink stamp, except that instead of ink we have sweat.  The technical term for the bit responsible is the eccrine glands present in the ridge skin secreting sweat. This is also most likely the reason they are called finger prints in the first place.  ;D
 

Offline CliffordK

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Why do we leave fingerprints?
« Reply #3 on: 16/10/2011 18:07:19 »
The question remains why we have evolved very distinct fingerprints.

5 million years ago, "nature" didn't predict the need for, or the existance of crime labs.

Obviously there are requirements for the more durable "thick skin" on our hands and feet, and "thin skin" on the rest of the body.

So, why the ridges?

Humans are a very tactile species.  With thin skin, hair provides good sensory feedback.  However, hair is impractical on the bottom of the feet and on the manipulation side of the hands.  The ridging likely aids with the flexibility of the skin, as well as acting like hair and improving sensory feedback.

Realizing that the ridging goes through all layers of the skin, the ridges may also aid with anchoring the skin to the underlying tissue, with benefits of the skin on the hands and feet tightly sticking to the underlying tissue, rather than being loose.

Excretions likely aid with longevity and flexibility of the skin.  Many other species also mark terratory with scents including those secreted from the paws.  While humans don't distinguish scents left behind by hands and feet, perhaps some of the secretions remain from an evolutionary past.  Certainly other animals respond to our scents.

The uniqueness, and the long-term stability of the ridging of the fingerprints is pretty extraordinary.  There is maturation, but otherwise general stability.  But, if one justified the ridges, then there would be no reason to expect all individuals to appear identical, or for them to change within a single individual.  There certainly are benefits for the skin on our hands and feet to recover from damage with minimal scaring, i.e. a stable structure.
 

Offline Don_1

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Why do we leave fingerprints?
« Reply #4 on: 24/10/2011 17:30:22 »
Because you're careless, try wearing gloves.

OOOOoooooh! What a give away! Honest officer, it wasn't me what filched that TV. What do you mean, 'what's that up my jumper, then?'.
 

Offline Airthumbs

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Why do we leave fingerprints?
« Reply #5 on: 24/10/2011 22:26:39 »
Our ridges in the skin also enable us to hold things more securely.
 

Offline damocles

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Why do we leave fingerprints?
« Reply #6 on: 25/10/2011 03:20:03 »
someone who chooses the pseudonym of "Airthumbs" should be really well qualified to deal with this one!
 

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Why do we leave fingerprints?
« Reply #7 on: 25/10/2011 10:21:27 »
Our ridges in the skin also enable us to hold things more securely.

Judging by the number of things (glasses and china in particular) that 'er indoors manages to break, I would guess that she leaves no finger prints at all!
 

Offline CliffordK

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Why do we leave fingerprints?
« Reply #8 on: 25/10/2011 10:56:04 »
Our ridges in the skin also enable us to hold things more securely.
Judging by the number of things (glasses and china in particular) that 'er indoors manages to break, I would guess that she leaves no finger prints at all!
Either that...
Or she has been augmenting the natural oils in the hands with lotions and other artificial oils.
 

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Why do we leave fingerprints?
« Reply #9 on: 26/10/2011 10:10:57 »
Our ridges in the skin also enable us to hold things more securely.
Judging by the number of things (glasses and china in particular) that 'er indoors manages to break, I would guess that she leaves no finger prints at all!
Either that...
Or she has been augmenting the natural oils in the hands with lotions and other artificial oils.

Verily you jest not! She has cremes, lotions and potions for just about everything: Day creme, night creme, face creme, eye creme, neck creme, left hand creme, right hand creme, this creme, that creme, the other creme!!!!

I must admit though, she put on a face mask the other day and result was an astonishing improvement. Unfortunately, she took the face mask off.
 

Offline Geezer

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Why do we leave fingerprints?
« Reply #10 on: 26/10/2011 19:09:28 »
Verily you jest not! She has cremes, lotions and potions for just about everything: Day creme, night creme, face creme, eye creme, neck creme, left hand creme, right hand creme, this creme, that creme, the other creme!!!!

I must admit though, she put on a face mask the other day and result was an astonishing improvement. Unfortunately, she took the face mask off.

Perhaps she would like to try this too also as well



 

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Why do we leave fingerprints?
« Reply #10 on: 26/10/2011 19:09:28 »

 

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