Our healing ability

[Motus]

In the womb, our cells divide to form our bodies.
After birth, our bodies have a certain degree of healing ability.
If our arm is removed, why doesn't it grow back, since it grew in the womb, and our bodies can repair themselves?

 

[larry lunchpail]

yours dosent? have you tried? mine sure does

 

[princess_ballet]

It is because you are no longer undergoing that process.

 

[Ondoher]

In the womb, our cells divide to form our bodies.
After birth, our bodies have a certain degree of healing ability.
If our arm is removed, why doesn't it grow back, since it grew in the womb, and our bodies can repair themselves?

One proposed reason is that many vertebrates have traded rapid scarring for regeneration. Here are a couple of links with some info.
http://www.cnsfoundation.org/newsletter/newsletter_48/newsletter_05.html
http://www.mult-sclerosis.org/news/Aug2001/MammalsRegenerateTissue.html

 

[Hydra009]

In the womb, our cells divide to form our bodies.
After birth, our bodies have a certain degree of healing ability.

That's true. Children under 6 years of age are capable of regenerating lost fingertips and the human liver retains its ability to regenerate throughout a person's lifetime.

If our arm is removed, why doesn't it grow back, since it grew in the womb, and our bodies can repair themselves?

Regeneration of lost body parts is pretty common in less complex lifeforms, such as worms, newts and hydras. In these creatures, cells neighboring the injury undergo a process called dedifferentiation where the cells revert to a more generalized stem-cell like state, then respecialize into a different type of cell that needs replacement. (Source)

However, for some reason, mammals (including humans) no longer have this ability to regrow lost limbs and severed nerve connections. It's an interesting question.

 

[Phred]

Different cells. The cells that divide and create your body are not the same as those that make up your body.

Hence all the chatter over the possibilities of stem cells. There is thought that thru the use of stem cells we might be able to regrow lost limbs.

And... here we go.

 

[Mistermystery]

It takes to much energy to regrow a new fully grown arm.

 

[princess_ballet]

Well, since this is in Evolution and Creation.

Wouldn't those individuals that were able to regrow an arm or other appendixes be better suited for survival, hence be the ones that survived and reproduced, leading to regrowth being a characteristic of humans?

So, why can't we do this? If evolution is thus true?

 

[Ondoher]

Well, since this is in Evolution and Creation.

Wouldn't those individuals that were able to regrow an arm or other appendixes be better suited for survival, hence be the ones that survived and reproduced, leading to regrowth being a characteristic of humans?

So, why can't we do this? If evolution is thus true?

Looking at the links I posted above, one proposal is that it became more fit to scar quickly in all injuries than it was to regenerate the occassional lost limb.

 

[Phred]

Well, since this is in Evolution and Creation.

Wouldn't those individuals that were able to regrow an arm or other appendixes be better suited for survival, hence be the ones that survived and reproduced, leading to regrowth being a characteristic of humans?

So, why can't we do this? If evolution is thus true?

Evolution is true... the strawman you present here is not.

Just because you imagine a trait to be better suited for survival doesn't mean it is. In order for the regrowth of an arm to have any effect, the organism first has to have that arm ripped off. In fact, whole populations of organisms would have to be losing limbs regularly for something like this to evolve as a trait...

Why can't we do this? If your God exists and created us all, why don't we have this ability?

 

[Sanguine]

the organism first has to have that arm ripped off. In fact, whole populations of organisms would have to be losing limbs regularly for something like this to evolve as a trait...

They would have to be losing it before sexual maturity as well. Add to this the amount their energy intake would have to surge during regeneration it becomes more of a 'nice to have' than a genuine selective advantage for hominids.

 

[Hydra009]

It would probably be a more efficient adaptation for humans to be smart enough to avoid danger in the first place so that most of them wouldn't need the ability to regrow lost limbs.

 

[Motus]

One proposed reason is that many vertebrates have traded rapid scarring for regeneration. Here are a couple of links with some info.
http://www.cnsfoundation.org/newsletter/newsletter_48/newsletter_05.html
http://www.mult-sclerosis.org/news/Aug2001/MammalsRegenerateTissue.html

Oh yea, stem cells! Now it seems like a dumb question..

 

[2_KwIcK_4_U]

lol yup my arm grows back all the time lol thas hysterical

 

[Mistermystery]

Oh yea, stem cells! Now it seems like a dumb question..

Believe me, there are worse questions on this board.