Does anybody know what this upside down Y is?

[bballman26]

I have the same exact hairline as David Beckham and I also have the same exact upside down Y on my head. It's not exactly an Y but almost. It shows up when my hair is buzzed between 1/4 inch to 1 inches in length. Below is the photo of exactly what I have with red arrows pointing to it. It's like a little strip of fine hair and then every where else it's very thick. I have no receding hairline and my hair density has been the same since 18 until now (26).

Here is the photo of David Beckham:
http://i39.tinypic.com/30tgcub.jpg

Here is the photo of the top of my head from 3 years ago:
http://i39.tinypic.com/2gt0x8p.jpg