Culture is like an iceberg. The tip of the iceberg is the smallest part. Most of the iceberg is submerged. The same is true for a culture. That which you can easily see – the behavior of people – is the smallest part of culture. It is external while the greatest part, internal culture, is beneath the water level of awareness. It is inside people’s heads.
While immigrants may assimilate there is more to culture than the way a person dresses and behaves. There is something deeper, something innate that remains after many generations.