Typology of students

At the university in which I work, it is nowadays time for the final examinations of many BA and MA students. In Italy, these final examinations focus on the thesis written by each student. Apart from the tutors of the thesis, there are other examiners who have had until that moment nothing to do with the thesis and may also not know the student. Since I work in a department of Oriental Studies, the examiners may teach each of the subjects taught there (from history of Indian art to Muslim right, Chinese language and so on).
I tend to like (or at least not to dislike, which is already quite unusual among my colleagues) sitting among the examiners. This is also a way to have an overview of students I would have never known if it were not for this chance. Statistically, the number of students I meet is non-influential, still I tend to notice that bright students tend to choose to write their final thesis on linguistic topics, and (in a minor amount) on philosophical ones. Students who might be bright human beings but seem to have less to do with academic research (and who often tend to do something completely different after they complete their degree) rather pick up history of art, sometimes religious topics and sometimes topics having to do with "contemporary societies" in Asia. Literature may also be chosen. Of course, there are many exceptions and I do not mean to say anything about the students as complete human beings. One of them became, for instance, an excellent fictional writer, after having written her thesis on the history of Chinese art. Still, these students tend not to keep on studying with a PhD, etc.
Why so? Are bright students just attracted by bright teachers (whatever they teach) or do they prefer challenging, "difficult" subjects? The first choice is no answer, since one could ask further why and if there are more bright teachers teaching a certain subject. The second is also no answer, since I doubt that something is intrinsically difficult and am rather inclined to think that the degree of difficulty depends on the depth required by the teacher. Nonetheless, this degree is also influenced by the general requirements of the wider cultural milieu of one's colleagues and seniors. Hence, nowadays in many parts of the world natural sciences are believed to be more important than humanities and this triggers bright young people to pick up natural sciences.


Do you notice similar patterns in the university/ies you know better?

(We look much less smart than the professors in the photo, at the university of Siena.)