Ship's cat

The ship's cat has been a common feature on many trading, exploration, and naval ships, and dates back to ancient times. Cats have been carried on ships for many reasons, the most important being to catch mice and rats. These rodents aboard a ship can cause damage to ropes, woodwork and eventually as technology progressed, electrical wiring. Also, rodents threatened the stores the ship carried. Rodents may devour the foodstuff carried to feed the crew, and could cause economic damage if the ship was carrying grain or similar substances as part of its cargo. Rats and mice were also sources of disease, which is dangerous for ships that are at sea for long periods of time. For example, rat fleas are carriers of plague and it is believed rats on ships were one of the main spreaders of the Black Death.

Cats naturally attack and kill these rodents. The natural ability of cats to adapt to new surroundings made them suitable for service on a ship. They also offered companionship and a sense of home, security and camaraderie to sailors who could be away from home for long periods, especially in times of war.

The domestication of cats is believed to date back some 9,500 years, and the practice of taking cats aboard boats and ships began not long afterwards. The Ancient Egyptians took cats on board Nile boats to catch birds in the thickets along the riverbanks. In the preliminary results of a genetic study published in September 2016, it was concluded that cats were also carried on trading ships to control rodents, and that practice was adopted by traders from other nations, even Vikings in northern Germany around the 8th to 11th century. This led to the spread of cats throughout the world, with the species eventually reaching nearly all parts of the world accessible by ship. Over the centuries their offspring developed into different breeds according to the climate in which they found themselves and the mates they took, as well as deliberate selection by humans. Phoenician cargo ships are thought to have brought the first domesticated cats to Europe in about 900 BC.

...
Wikipedia