In the wild, the only tiger subspecies in the wild that have been observed to carry the white color is the Bengal tiger. Even all the white tigers that have been held captive are partly Bengal in subspecies. It is believed that the rare recessive gene that carries the white color comes from Bengal tigers only.
It is difficult to classify viruses as living organisms because they are not made of cells. They only become alive when they find a host i.e. a living cell to live in.ome algae are difficult to classify because they sometimes do not properly fit in one of the kingdoms since they may have characteristics from a few of the kingdoms.
It is hard to draw up a classification of genres. This is because Â«a genre is easier to recognize than to defineÂ» and therefore Â«most academics today agree that any genre cannot be identified in a rigid way. Furthermore, different countries and cultures define genres in different ways. A typical example are war movies.