1) On a scale of complexity worldwide German is not really very complex. 2) How hard a language seems to be to learn is related more to what your first language is than on how complex it is. read more
As for biological species, a language does not evolve with a purpose, it just adjusts to the actual environment and the result happens to be more or less complex. If you think German is complex, have a look at the Navajo language. read more
Mark Twain in his humorous account of “The Awful German Language” described this German grammar peculiarity in this way:"Every noun has a gender, and there is no sense or system in the distribution; so the gender of each must be learned separately and by heart. There is no other way. To do this one has to have a memory like a memorandum-book. read more
German is basically a northern European language with an incredibly complex grammar. Words can be brought together to mean new concepts, and one can easily end with long tongue twisters such as"Fernsehgerät" when a simple"TV" will suffice in most other western languages. read more