It has been claimed e.g. in
Dalit Voice journal that Dalits (Untouchables) are the Blacks of India. There is an element of truth in this, but this is not the whole truth.
Race has been discredited as a scientific concept and physical features were only one factor in the evolution of the caste system. Caste has many components out of which skin colour is but one and it can be misleading one at times, as black Brahmins and fair skinned untouchables do exist and not in small numbers either. Generally speaking most people from the same area in India tend to have similar physical features. Taking race as the major factor in the evolution of the caste system fails to answer the question of why racism in Africa and Aryanisation/Brahminisation in India should have led to two different types of social systems although the exploitative nature of the two was the same. Africa had also produced its own version of the caste system although not on the same scale as in India. Exclusively focusing on 'race' also leads to the denial of class as a factor in caste formation. The common feature between racism and casteism is that the first one is the product of 19th and 20th century Western colonialism and the second one being the product of internal colonisation of India.
These 2 theoretical conceptual issues came up in practice in Durban South Africa in 2001 at WCAR when as a tactical measure, the Indian Government claimed that caste could not be equated to race. This was countered by Dalit activists by raising the slogan "Caste is Racism and Worse".
For differences between caste and race see video by Prof Rachel McDermott of Harvard.
See the blog on caste and race and on Indian Government sponsored anthropologists. See also Tehelka news item on WCAR controversy and the Rafto Prize, and Dag Erik Berg's academic paper on WCAR .