The Naked Scientists

The Naked Scientists Forum

Author Topic: Why do humans have fingernails and toenails?  (Read 1575 times)

Offline chris

  • Neilep Level Member
  • ******
  • Posts: 5336
  • Thanked: 65 times
  • The Naked Scientist
    • View Profile
    • The Naked Scientists
Why do humans have fingernails and toenails?
« on: 02/01/2014 20:26:43 »
What is the evolutionary advantage of fingernails and toenails? And when did they first appear and how?


 

Offline CliffordK

  • Neilep Level Member
  • ******
  • Posts: 6321
  • Thanked: 3 times
  • Site Moderator
    • View Profile
Re: Why do humans have fingernails and toenails?
« Reply #1 on: 02/01/2014 21:20:23 »
The fingernails and toenails would have evolved from claws. 

Fingernails are certainly useful for many tasks, such as grabbing that little notch in pocket knife blades to open them up.  But, presumably there would be some more natural tasks too, perhaps including digging or tearing open some things based on small cracks. 

According to Wikipedia, a squirrel or something that climbs on trunks and tree branches larger than the animal would have claws to dig into the bark.  On the other hand, animals that tend to climb smaller branches where the hand is wrapped around the branch would have fingers and pads similar to our own.
 

Offline RD

  • Neilep Level Member
  • ******
  • Posts: 8126
  • Thanked: 53 times
    • View Profile
Re: Why do humans have fingernails and toenails?
« Reply #2 on: 02/01/2014 21:24:59 »
What is the evolutionary advantage of fingernails and toenails?

Useful in grooming, (e.g. picking off insects from oneself and others) ...



... and starting rolls of adhesive tape :)
« Last Edit: 02/01/2014 21:42:32 by RD »
 

Offline CliffordK

  • Neilep Level Member
  • ******
  • Posts: 6321
  • Thanked: 3 times
  • Site Moderator
    • View Profile
Re: Why do humans have fingernails and toenails?
« Reply #3 on: 02/01/2014 21:52:09 »
Is there an evolutionary advantage to retain toenails, other than the temptation to paint them with bright colors?

Perhaps there is no significant evolutionary advantage to loose them.
 

The Naked Scientists Forum

Re: Why do humans have fingernails and toenails?
« Reply #3 on: 02/01/2014 21:52:09 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums