Cats like to think they don't need us, but a new study into feline genetics has indicated that the global kitty population only boomed when they moved in with humans. The research, presented last week and reported by Nature, seems to show two distinct waves of growth in cat numbers: first around 10,000 years ago as humans first started cultivating crops, and second as we started taking to the seas.

Cat families from Egypt ended up in Bulgaria

The researchers behind the study sequenced DNA from more than 200 cats of various generations discovered in tombs, burial sites, and other archaeological sites, from as far back as 15,000 years ago, to animals born in the 1700s. Even among this limited sample, they found links in mitochondrial DNA, genetic information passed down through the maternal line only — suggesting that cat families had either moved or been taken near to human civilizations. This mitochondrial connection was spotted between wild cats found in the Middle East and creatures discovered close to the fertile east Mediterranean, a region well-known for its early agriculture. Researchers also found connections between cats that lived millennia later, linking mummified kitties discovered in Egyptian tombs with cats found as far away as Bulgaria, Turkey, and sub-Sarahan Africa.

Agriculture was a catalyst for cat populations, the study's authors say, because the need to store grain and other crops drew nearby rodents — rodents that in turn became food for wily felines. Ancient humans presumably appreciated that these new arrivals were helping keep their stores free from infestation, and as a bonus, were super cute. A second population explosion appeared to coincide with the advent of boat travel, where a ship's cat could keep vital food stores safe from rats and mice that stowed away on board. Perhaps the most exciting part of the study is the mention that a cat was discovered in a thousand-year-old Viking burial site, conjuring up the image of horn-hatted kitties sailing the ocean on longboats.

The report's authors say it represents some of the first serious studies into how cats came to live alongside us. "We don't know the history of ancient cats," evolutionary geneticist and study author Eva-Maria Geigl says. "We do not know their origin, we don't know how their dispersal occurred." As befitting the animals themselves, cats are a mystery while dogs, on the other hand, have had their backgrounds carefully mapped out. But that's probably only fair — dogs used to be wolves, and now look at what we've done to them.