Identical Twins?

[the freak]

I know these twins who are identical twin brothers, but the one who is older by 5 minutes is 2 inches shorter, a little heavier and his head appears to be a teensie tiny bit blockier. They dress very differently and have different piercings and stuff, but when they dress the same you can't tell them apart. What my question is though, do these differences (face shape, weight etc) still make them identical? I know height doesn't matter, cause the Olsen twins aren't the same height, but I'm just rambling on, and I know alot of what I just said was pointless but it's mainly the head shape I want to know about. Thanks in advance, and sorry if I don't make sense.

[Gef]

If they both come from the same egg (and sperm) then they are identical genetically (have exactly the same genes). However there are many factors after the egg "splits" and in growing up, which cause them not to be "identical" to the eye. I suppose head shape could be affected at delivery.

I'm not an expert so I'll wait to be corrected.

[AngelofDeath]

Identical twins are formed when the egg splits into two as opposed to regular twins that are formed from two separate eggs. This means that they have exactly the same genes. They will have the same blood group, same eye and hair colour etc. However, as they grow they will be subjected to different stimuli and may be exposed to different environments that will allow for differences to appear.

For instance if one was to be put on steroids as a youngster, for some medical condition, it could stunt their growth. A difference in diet could also affect the way they grow, as could other medical conditions that are suffered by one and not the other.

So, in answer to your question, yes they are still identical twins and always will be.

[Loosehead]

"identical" in this context means that they have the same DNA, they are a natural clone of each other, it does not mean that they will always be identical in the common sense of the adjective.

[artee]

It's crazy isn't it. but true. One explanation of the difference in appearance is that it depends on the rate of the egg splitting as well. (If the split takes too long this can cause siamese twins I've heard).
Sometimes I wonder, when identicals look very different, is if  there were two eggs but they implanted one on top of the other, hence allowing only one placenta and one bag for them to grow in.
Here's another opposite example...Fraternal twins with part chinese mother and part maori mother. When they were first born one looked like a little chinese baby, with a very round face, and brown in colouring. The other one, like his father with a longer slimmer face and very fair in colour. (both boys)  6 weeks later you could not tell them apart. They looked even more identical than many id twins. Later there was a little bit of a difference so that if you saw them both together you could be pretty dure you got the names right, but when apart not so sure.
So it is fascinating .....

[artee]

PS  ..correction ..Part Maori father.

[spammylou]

DNA makes them identical. But as a Mum to id twins, I know mine apart as like you said, there are differences, such as weight/face shape.  The thing that makes the difference is whether or not a gene is triggered, for example, if both carry a gene that would start off a hereditary disease could lie dormant in one and then be triggered in the other.  I could not think of another example to use but that is apparantly why there are differences although identical.

[snoteater]

monozygotic versus dyzygotic.

[emmacherise2]

are you sure they are identical?? Many people get confused about this, as it is very easy to confuse unidentical twins with identical twins in the womb, as the placenta's are often fused or look like just one.

There is a good chance they are identical though.. the differences you point out about these twins are all environmental. You said the older twin was shorter.. maybe he smoked, took medication, lifted weights whilst he was still growing.. as alot of things can stunt your growth these days.. also, if one twin is slightly stockier anyway.. or slightly heavier.. his face and neck will probably have extra fat or muscle.. which in turn makes it look a different shape.

This means that although they are identical twins 9if they are!!) then they only look different due to things that happned after they were born.. things to do with the way they have lived and the things around them....

for example.. if two identical twins are completely different complexions.. one may use the sunbed twice a week and the other may wear sunscreen all the time.. or just not go on the sunbed!! sounds stupid but its the same thing!! environmental differences, not genetic!

hope that helps