It strikes me that although there are diverse cultures in the world, there are basic elements of life that we all share...being born, being a child, growing up, having to make our way, then shuffling the mortal coil and passing away (perhaps to go onto the next world?)
Here are my 3 entries for cultures of the world based on this context.
THE YOUNG - Of Tibetan descent, the Sherpa people live in the Khumbu region fo Nepal high up in the Himalayas. This little fellow could only have been 3 years old, yet the exposure to UV at high altitude made him look older (none the less a happy chap!)
http://www.pbase.com/davecollier/image/78851263
THE MIDDLE AGED - this market trader in Islamabad (Pakistan) was very proud of his dates. The open bazaar in Islamabad was extremely busy and hot - yet this man was keeping cool.
http://www.pbase.com/davecollier/image/65276466
THE DEAD - the Hindu tradition is that the dead should be cremated and their ashes scattered into a holy river. In this case you can see a body bound in cloth at the foot of a crematory gatt at the temple of Pashupatinath in Kathmandu, Nepal. There are several gatts, and the dead are cremating in order of their status from left to right...only the Brahman class get cremated to the far right. Even in death society makes class distinctions.
http://www.pbase.com/davecollier/image/78790229