I am fortunate to live in a city with ethnic, cultural and age diversity. I believe a balanced demographic provides a richness in society that is not apparent in more close-knit communities. It is in stark contrast with, for example, the area where my parents lived during the last few decades of their lives, which I won't name for fear of upsetting the natives, but suffice to say it is known by some as "Costa Geriatrica." In my opinion, the narrowness of their community and in particular the predominance of elderly citizens, accelerated their mental, rather than physical, ageing process.
Diversity has its problems but only for those who don't embrace it and feel more comfortable with a peer group of similar attributes, such as skin colour, religion, place of birth, sporting preference, age, sexuality .... whatever. The optimum mix of individuals varies dependant upon the type of activity - it's horses for courses. In the business world, for example, the types of contributors who would be brought together for, say, a company acquisition, would be quite different from a team to promote a new product, or a group engaged in cutting-edge technology Research and Development activities.
I recently witnessed optimal diversity in the animal world when I had the opportunity to accompany a well-respected and highly-competent dog walker. Big Stan's Dog Walking, http://bigstansdogwalking.co.uk, is a sole trader business, owned and operated by Big Stan, better known to his customers and friends simply as Stan! To watch Stan walking his dogs is 'diversity in action'! He collects the dogs, of all breeds, sizes, ages and temperaments, from their homes and they travel in his SUV, without cages, to various local parks. He groups the dogs for collection into two categories, Hoodies and Oldies. The 'labels' are misleading because age doesn't really come into it but rather the level of boisterousness - high for Hoodies and not quite so high for Oldies. The way the different dogs relate to each other and to Stan is a joy to watch. They are all off the lead and they are well-behaved with no aggression towards each other or other dogs in the park.
That dog-walking experience demonstrated to me more in half a day than many managers learn (or don't!) throughout their careers on organisational dynamics. A happy team is a productive team, whether it's dogs on a walk or a group of tradespersons building a house. The labels, such as hoodies, oldies, labrador, poodle, mongrel, carpenter, bricklayer, electrician ...., are interesting but of secondary importance to what, in my opinion, are the prime ingredients for success - diversity and harmony. Now some would contend that financial incentives also have a part to play but returning to the doggie world and in the words of Josh Billings:
Money will buy a pretty good dog, but it won't buy the wag of his tail.