A new international study is giving scientists more insight into understanding the process of the domestication of animals.
Jeffrey Good, an assistant professor of biological sciences at the University of Montana, is one of the co-authors of the study. Good worked with an international team of scientists on the report trying to better understand the genetic changes that transform wild animals into domesticated ones.
While domestication of other animals, such as cows, dogs and sheep started between 9,000 and 15,000 years ago, domestication of rabbits began much more recently, around 1,400 years ago.
Good said the first domesticated rabbits where raised in monasteries in southern France to be used as a food source. The story of why, he said, is the Catholic Church decided young rabbits were not considered meat, but rather fish, and could be eaten during Lent.
Rabbits were a useful domestication comparison because the wild source population still exists. This is unlike cows, Good said, that were domesticated from aurochsen, a species now extinct in the wild. With dogs, which domesticated from wolves, the difficulty is in finding out when or where.
“It’s hard to tell what were the key differences that shifted the wolf to a dog,” Good said.
The research team sequenced the genome of a domestic rabbit to create a reference genome to use as a base standard. They then sequenced the genomes of six breeds of domestic rabbits and wild rabbits from 14 locations around the Iberian Peninsula and southern France.
In the transition from wild to domestic, the study found rabbits lost the strong flight response they had to their natural predators, as well as humans. Good said this wasn’t the result of any one big change, more the accumulation of many smaller ones.
These changes led to different behaviors in domesticated rabbits, making them more docile and suppressing their natural survival instincts. Often in the domestication process, Good said, there are a few radical mutations in genes that are fixed one way or the other for different versions of an animal. With rabbits, the researches found that the differences were a much more complicated genetic shift, a broader group of smaller changes.
“What had to start in the beginning, you had to take an animal that isn’t comfortable living with humans, isn’t comfortable living in large populations, and is a seasonal breeder, and you have to change all of that. But it’s complex enough we can’t just say this one gene changed and that made it lose its fear response,” Good said.
The full study was published Aug. 28 in Science magazine.
Good said the next step that will be taken by other research teams is using the resource of a fully sequenced rabbit genome to examine individual traits. Having that genome will be a useful resource in the future for scientists looking to study many different things about rabbits.
“They are interested in using breeding experiments between wild and domestic rabbits to see how specific gene differences affect traits and behaviors,” he said.