In a general sense, every distinct species on earth is an example of macroevolution. Each species is distinct from every other species in the world, yet it shares a common ancestry with all other forms of life. Macroevolution is the process by which humans diverged from apes, apes from other mammals, mammals from reptiles and air-breathing vertebrates from fish.
Macroevolution is the long-term accumulation of small changes in gene frequency within a species. These changes usually build up as a result of one population becoming isolated from the rest of the species. Over time, these genetic differences become so pronounced that the population undergoing the shift can no longer breed with the ancestral group if the two groups come back into contact.
A relatively recent example of this process is found in the human descent from apelike ancestors. Between 6 and 8 million years ago, two distinct lineages diverged, with one line leading to modern humans and the other to the two living species of chimpanzee. On a longer timescale, humans, chimpanzees and gorillas diverged from other apes, such as orangutans. On still longer timescales, mammals and birds diverged from reptiles, reptiles diverged from amphibians, and all tetrapods diverged from fish.