Explain how two different species of rabbits could have developed from a common ancestor?

The population of rabbits (common ancestor) must have gotten seperated to form two populations. This could have happened due to a geographical barrier (such as an earthquake). These two environment must have had different environmental conditions leading to genetic variation in each population. The rabbits that better adapt to their environment will survive and pass this useful gene to their offspring. After a period of time, because the two population of rabbits are now very different, they will not be able to interbreed successfully.