In The Family Way

Mmm. I'm skipping around a little bit while I twiddle away on the side-lines on some of the bigger projects I'm pulling together for this blog, but while I was roaming around collecting data, I decided to quickly bring you a little seminar in Biology and Genetics.

Along with my general sense that Paul McCartney of the last  47 or so years doesn't look like himself,  his children also don't resemble him as much as one might expect. (Paul comparisons is a matter I will go into a bit in a future post, but I feel there are sooo many resources for information on the face and feature matching projects, I mostly will leave it to those who have already worked so hard on it),

We will likely never have the opportunity to actually examine Paul McCartney's DNA to determine if it's really him these day; so our second best option is to examine the effects of his genetics in phenotypic representation among his offspring. I can't help but look at James McCartney, specifically and thinking, "did Linda hook up with a Scottish milkman one afternoon???".

A couple quick points about genetics and parentage:
1. It is evolutionarily beneficial for a baby to resemble their father strongly shortly after birth. This helps the father recognize the baby as his legitimate offspring and increases the likelihood of the father providing for the child's resources and safety until it matures to mating age. As the child grows older, he or she will likely start incorporating more of the mother's features, and blending the two into a distinct genetic phenotype blend, making them look unique, but with a hint of features from both parents.
2. Some features blend or just create a mixture of the two in some manner, but a few features can be specific genetic markers- eye color and hair color and/or texture.  You may have learned about the punnett square in high school, using eye and hair color. For those who need a brush up:

Genes come in pairs- you get one from your mother, one from your father and those two have a special relationship that determines how the genetic information actually results in features.

Eye color and Hair color work in a Dominant/Recessive relationship. For eyes Brown is dominant, blue and hazel are recessive. For hair color Brown is dominant, blond and red are recessive; though hair color can sometimes result in a slight mixture. So, For eyes if you have a Dominant Brown (B) gene from dad, and a recessive Blue gene from Mom (b), your eyes will be brown (Bb), but if you breed with someone with blue eyes (bb) there is a 50% chance of your child having blue eyes.But- if both of your parents had brown eyes, there is between 25% chance-100% chance your genes are BB (mean = 62.5%) . If both of Their parents had brown eyes, you most likely have 2 dominant Brown eye genes, and in that case, if you mate with someone with blue eyes, you have a statistical 100% chance of having a child with brown eyes. (genetic mistakes happen, so don't write me about your cousin with purple eyes, go take a class).


With a bit of genealogical information, we can predict the likelihood of someones offspring's genetic/phenotype make-up.

Hair color works pretty much the same as eye color. The dominant browns and blacks overpower the recessive reds and blonds when they are together. Sometimes hair color will result in a little "blend" like red highlights, or a lighter version of brown.

Why am I talking about this boring stuff on my Blog??!!!!

Ok, we'll move on. First I'll show a little photo collage of Paul McCartney's childrens' family tree (except Beatrice- I couldn't find her grandparents pictures).

Top left is Paul and Mike McCartney with their mom and dad as children. Note mother, father and 2 children all have brown hair...this is strongly indicative of a (BB) genotype. Next we have dark hair, dark eyed young Paul. Bottom Left we have an Eastman family photo. Linda is in the middle bottom between her parents, and her 3 siblings behind her...they're all looking pretty Brown haired, except maybe the boy shares her lighter dish-water blond color. She might be one of the rarer Bb phenotypes that come out blended lighter, but I'm thinking both of her parents have a blond gene in their pool, and she got lucky on the 25% chance. I'm guessing she's (bb), we'll just go with that for good measure.

So, for at least Paul and Linda's 3 children, their Punnett square is most likely BB/bb, so their children only have a 0% chance of being blond, or blue eyed; unless Paul has Bb genes, which bumps it up to a 50% probability. For Heather we can guess the (bb) without really seeing her parents, too, so Beatrice likely got the same square, and the same 0-50% (mean = 25%) chance.

Mary McCartney does have the brown hair, brown eyes, she also closely resembles her maternal grandmother. The rest have blond hair. James has brown eyes, but Stella and Beatrice have blue. So, 1 out of the 4 share phenotypic hair color with McCartney, instead of the predicted 2 out of 4, or 4 of 4 as most likely. 2 out of 4 have the same eye color, but since I can't determine his mother or fathers eye color for certain (at least one had brown eyes, though, but one could have had blue giving him Bb, and a 50% chance of blue eyed children). There's only about 20-49% chance of having light eyes if you live in the Liverpool area of England, but it increases to up to 79% chance just a hairs width more north. Blue eye distribution in Europe

At any rate, his children (with the possible exception of Mary, who I'd argue resembles her Grandmother mostly) bear very little visible resemblance to him, as he looked when a younger man, nor his brother (older or younger), for that matter. If I had to pick them out of a line-up for family traits, I'd never assume James, Stella or Beatrice were his children. Their mothers'- YES, certainly, they all resemble their mother, so we know they weren't adopted, ha ha.  

Just for fun, I'm adding in a picture of Paul's reputed illegitimate children to the family photo. Thanks to Dr. Tomoculous for the added research! :) You can find more links about them in the comments section. <Link to his story>

I'm not trying to prove anything here....just pointing it out.

What about the other Beatle families? How much resemblance is there between their kids and themselves?