Yes, some scientific research, e.g. cited in a declaration of the UNESCO against the concept of race, proves that the idea of “different races of mankind” has become obsolete, because the biological diversity of human beings doesn't justify the assumption of general biological differences: Even though the morphologic differences appear quite essential regarding the whole world, the genetic variance is not. The usage of the concept of races can therefore be regarded as one-sided and it fosters the upbringing of arbitrary and misleading social cognitions and ideas. It supports the idea of biologically justified inequalities, the classification of some people as more valuable than others (called “racism”). It makes you think that, when you see someone, you know his-her “truth”, you can judge the personality from the looks.

But note: There might be a lot of studies that say the opposite, research is never free from ideology, and therefore it is more important to question the creation and necessity of differences.