Why do we have different skin complexion?

Lately we have been observing a spike in racism related incidents since a couple of years. The fundamental question persist. Why do we look different? Is it due to the evolution process?

The answer is yes. In around 1835, Charles Darwin on his exploration voyage arrived on Galapagos island near Ecuador where he made a startling discovery. He observed different variations of a songbird called native finches. The Galapagos islands were a group of 13 island and he observed different variations on different islands.