After the battle at Kosovo 1389, when the Ottomans completely defeated the Serbian army, which lead to a catastrophic reduction of the male population, something took place which forever changed that people in its entirety. According to claims of historians in the entire Serbia there were only 200 thousand men left. Defeated and destroyed, Serbs became a part of the grand Ottoman empire and so suffered the worst fate of a looser. After the victory the Ottomans ruled over Serbia and in the long history of 500 years in entirety they changed the demographic image of the country. Namely, Turkish soldiers married Serbian women and girls or even raped them which resulted in every other child in Serbia, having a Turk as a father. That's why there is not one family in Serbia which doesn't have Turkish genes in their heritage. All of this unquestionably reflected in the physical appearance of the Serbian people which is very similar to the Turkish people which is especially evident in the facial features, namely, a larger part of the population has dark hair and eyes, just like the Turks. Because of this historical but also genetic connectedness, everything that was Turkish became an inseparable part of the Serbian identity from the Turkish cuisine, language, music and even mentality.
Today when you compare Serbs and Turks, besides physical similarity, you will notice some important links: both people are extremely nationalistically driven, both people strive for creating Grand Turkey i.e. Grand Serbia, both people do not accept minorities, both people committed genocide which they deny - over Armenians and Bosniaks, both people are trying to assimilate other people around them, both people pretend to be great religious people, both people claim other's cultural heritage as their own, etc. There are too many similarities in order to conclude something else instead of that they are brothers i.e. same people.
Bosniaks - one of the best genetically preserved people in Europe
Luckily, Bosniaks didn't have the same fate under the Ottoman rule since by converting to Islam they were spared all of the negative events which struck the Serbian people. Today, out of historical but also genetic research we know that Bosniaks are one of the rare European people which can brag with a large percentage of racial purity. This was noticed long time ago by Karl Steiner, doctor in Ljubinja, which in his work "Bosnian folk medicine" writes the following: "Bodily the tall man from Bosnia and Herzegovina represents undoubtedly the most beautiful type of South Slavic-Illyrian racial mixture. He is taller from his neighbours in Dalmatia, Croatia and Slavonia, his chest are powerfully kept, musculature firm and hinged; smooth or weak curly, brown or dark hair and black eyes we see among the members of all three religions, but as often brothers are similar but yet different, similarly our Muslims, Orthodox and Christians show certain characteristics, which through centuries came about due to mixture in breeding. For example among the Christians and Muslims the iris of the eyes is mostly light, often blue or yellowish, while eyes among the Orthodox are usually darker, often black. Among the Muslim and Catholic children one can often see light blue hair, soft, skin white as milk, generally typical Aryan type, but the hair and skin colour will darken bit by bit, while these characteristic among the Orthodox are rare."
Unlike the extremely large genetic mixture between Serbs and Ottomans in Serbia, in Bosnia and Herzegovina there is a completely different situation about which Ćiro Truhelka, archaeologist and historian, wrote the following in his anthropological study:
"Endogamy was among the Bosniaks (Muslims in Bosnia) so strict, that in my time I knew a dozen Bey families, which intermarried and they wouldn't allow in their harem women which were out of this circle, though they were from the best homes. Because of the mentioned reasons mixed marriages between the Ottoman and Bosnian Muslims were extremely rare and without evident effect on shaping the race."
Endogamy and with it harem enclosure were the most successful measure of protection of racial element in Bosnia, and I believe that I can say, that rare ethnic groups in Europe managed to preserve their identity like the Bosniaks in Bosnia. The merit goes to harem exclusivity, which in this case preserved racial characteristics of the forefathers. Similarly it is familiar that there was antagonism between the Bosnian Muslims and Ottomans and that the Bosniaks dreaded from marrying their daughters to so called Turkuše (superlative of Turk), that antagonism often gained a dangerous political form, and was the cause of revolts.