Andrew Masterson
Andrew Masterson is a former editor of Cosmos.
In the Christian religion, the period known as Lent lasts for 40 days, winding up just before Easter, and involves many restrictions, not the least of them dietary.
Among some variants of the religion, notably Roman Catholicism, the consumption of meat is forbidden during certain days in Lent. In days gone by, this proscription caused many issues for the devout. Food in general was scarce, and few could afford to be picky. Also, of course, meat tastes nice.
Breaking the rules, however, was a serious matter. Eating meat on a fasting day was considered a sin. The local clergy were likely to order penance when wrongdoers confessed to an illicit sausage – and the wrath of the offended Almighty could only be imagined.
Ever a practical sort of chap – the story goes – in 600 CE Pope Gregory I came up with a handy hack for the hungry devout. Rabbit foetuses, he announced, were fish, and therefore could be consumed without sin. From that day on, rabbit keeping became a popular hobby.
That’s the story, anyway, told and retold thousands of times.
There’s only one problem, however. According to geneticists at the University of Oxford in the UK, it’s a load of rubbish. And to prove it, they’ve published a satisfyingly detailed molecular analysis in the journal Trends in Ecology and Evolution.
A team led by Evan Irving-Pease set out to determine whether the domestication of rabbits could be tied to Pope Gregory’s fast-busting announcement. If 600 CE was indeed a valid date for rabbits becoming domestic livestock, the researchers reasoned, then the evidence should be present in the animals’ genome.
And it should have been easy to find. Wild rabbits are still plentiful in Europe, so comparing the genome of a fluffy domesticated animal with that of a lean, mean wild specimen (and knowing the average rate at which mutations occur) should reveal the point at which wild and household variants last shared a common ancestor.
Irving-Pease and his colleagues were encouraged in their work by a 2011 analysis of domestic rabbit gene structure, published in the journal Molecular Biology and Evolution.
That study – which involved sequencing 16 regions of rabbit genome in both wild and domesticated specimens – found it likely that domestication had begun in France, using an initial population of only around 1200 animals, about 1500 years ago. It was a date conveniently close to the putative timing the pope’s edict.
Using a combination of genetic and archaeological evidence, the Oxford team found the picture to be much less clear – and the date at which rabbits were possibly first domesticated much, much earlier.
The genetic evidence suggests that French wild and domestic rabbits last shared a common ancestor somewhere between 12,200 and 17,700 years ago – way, way before Lent, or Christianity as a whole, was invented.
Although there is considerable evidence that rabbit was on the menu in parts of Europe during the Palaeolithic period, which began some 10,000 years ago, Irving-Pease and his colleagues acknowledge that the genetic ancestral split is not necessarily proof that a domestication event took place more than 12 millennia ago.
The timing of the divergence, they note, coincides with a great ice age – known as the Last Glacial Maximum – during which much of the rabbits’ natural range was covered by ice sheets. It’s possible that the two variants became separated due to physical barriers.
Nevertheless, there is also ample evidence in the archaeological and historical records to show that rabbits were being bred and kept long before 600 CE. The Roman author Varro, writing in the first century BCE in what is today Spain, describes the keeping of rabbits in a leporarium. He also notes that his wife used to put them in hutches to fatten them before they ended up on the dinner table.
A century later, the great Roman naturalist Pliny the Elder cites foetal rabbits – known as laurices – as a rather delicious food (but gives no indication that he thought they were fish).
These references are, of course, familiar to various researchers who have tried to tease out the story behind pet rabbits, but oddly they are usually rejected on the grounds that the types of animal-keeping described did not involve husbandry and therefore can’t be considered bona fide acts of intentional domestication.
The Oxford team dismisses these objections as methodological and semantic fripperies.
“The historical record does not support the narrative built upon it since there was no papal edict, no dispensation to eat laurices, and no historical or archaeological evidence that the practice was commonplace,” the scientists write.
The willingness of scholars to believe the Pope Gregory story, they add, “reveals how frequently the domestication process is misconstrued as a discrete event”.
Rather, they say, it needs to be regarded as a process, a series of gradual shifts in the relationship between humans and the species being domesticated. Hunting during the Ice Age, leporaria during the Roman period, Medieval rabbit-keeping, and, indeed, the very modern habit of breeding rabbits specifically as novelty pets, are all part of the domestication process, and no single event can be regarded as the defining moment.
Especially, they suggest, an event that never happened.
