By Charlotte Owen
People tend to shudder at the thought of rats – but is there really anything to be scared of?
Rats thrive wherever there are people, since we tend to create the perfect conditions for them, but the ubiquitous brown rat (Rattus norvegicus) has only been here since the 18th century. Before then, the only species present was the black rat (Rattus rattus), an exotic import from southern India that hitched a lift here with the Romans. These rats were natural tree-dwellers accustomed to a much kinder climate, so they were dependent on the warmth of human dwellings for survival and often lived in thatched roofs, pilfering spilled grain. Despite this, there’s no evidence they were ever numerous enough to be considered an agricultural pest but they’ve long been blamed for one of the deadliest disease outbreaks in human history. The Black Death originated in Asia and first arrived in Europe in 1347, transmitted by infected fleas. While black rats certainly played a role as carriers, there is still debate about whether they were a significant long-term reservoir of the plague.
Either way, the brown rat hadn’t even arrived here at that point in history. They first jumped ship in London ports in the 1700s, having stowed away on trade routes from China and Mongolia, and the British landscape suited them perfectly. They soon out-competed the black rat, which is now almost extinct here, and by Victorian times professional rat catchers were doing a roaring trade. As a surprising spinoff from the pest control business, any rats with unusual markings were spared the rat pits and sold on as pets to well-bred young women, including Beatrix Potter and even Queen Victoria herself. Rats have since been fully domesticated and are still popular pets today, due to their intelligent and social nature, while legions of lab rats have enabled significant scientific advances thanks to their genetic similarity to humans (our genomes are 90% identical). Behavioural studies have also shown that rats can feel empathy and regret, they laugh when tickled and will forsake chocolate to help a friend in distress - all admirable qualities, and really not spooky at all.