New DNA evidence shows there may have been only five different dog breeds 11,000 years ago.
This means that we can trace all kinds of dogs back to at least one of these five types.
The research is based on 27 different canine specimens from across Europe, parts of the Turkey and the Middle East, and Siberia.
"The dog is the oldest domesticated [meaning kept as a pet] animal and has a very long relationship with humans," said the projects lead author, Anders Bergstrom.
"Understanding the history of dogs teaches us not just about their history, but also about our history."
The study looks back to when humans were still hunters, and dogs were their helpful companions.
At some point during the Ice Age, the study suggests that that dogs had mixed and spread throughout Europe.
"Although the European dogs we see today come in such an extraordinary array of shapes and forms, genetically they derive from only a very narrow subset of the diversity that used to exist" explained Mr Bergstrom.