Why does our hair turn grey?

This may be a short post. Kid-induced sleep deprivation is making my eyes too blurry to type and my brain too mushy to think, but, it turns out, probably not turning my hair grey.

The most interesting thing I found out in this week's research (which, I have to admit, has not been quite as thorough as last week's, due to babies and their midnight parties) is that grey hair is actually just a combination of white hair (or transparent hair, to be precise) and dark hair. 

So George Clooney's 'salt and pepper' look, as well as having a certain ring to it, is quite aptly named.

Polars bears actually have transparent hairs that reflect the light and appear 

white. Their skin underneath is black to absorb the sun and keep them warm.

What has caused the Cloonster - and Grandma - to go grey? Hair is attached to our heads by roots, which are encased in little tubes of skin called follicles. These follicles are fed colour information from cells called melanin that exist just below the skin's surface. As we get older, the amount of melanin we make slows down, causing some of our hairs to grow without colour. Whether it looks white or grey depends on how many colourless hairs we have and the way the light reflects on them. Very old people often have completely white hair, because there are no coloured hairs left to cause the grey look.

The particular shade of hair you are born with is governed by genetics. The same goes for going grey. If your grandfather went grey at 30, you probably will too, but there are also other reasons why your hair might go grey faster or slower than your brother's, including the climate and level of toxins in your  environment. Stress doesn't seem to have much impact, according to scientists, but I'm sure there are parents, teachers, and perhaps CEOs out there who can look back on photos of more relaxed days and disagree.

I hope that explains it to the adults. For those needing a toddler version, here goes (haaaa):

Hair grows out of our heads from roots, which have colour in them. As people get old, they run out of colour. 

Happy birthday to you

This week we went to a four-year-old's birthday party. Batman was there, but that's another story. My little boy loves birthday parties, mostly because he loves cake. He loves the taste of it, obviously, but he also loves the process of bringing out the birthday cake, the song, the candles, the cutting. So far, he is more interested in the cake than he is in presents.

It is a pretty awesome tradition, especially in a western culture that doesn't have many traditions left.

My Why for this week: why do we blow out candles on the birthday cake? And, although I'm sure a toddler would never ask this, but because I'm curious, is the birthday cake tradition universal?

My big boy on his first birthday