Around 15 years ago, I created a Facebook page for my cat, Sandi. Friends thought it was weird. Today, social media accounts for cats attract millions of followers, cats travel in backpacks and prams, and surveys consistently show that the overwhelming majority of owners regard their pets as family.

I’ve previously written about how cats became domesticated. But domestication isn’t necessarily a process with an endpoint. Could it still be continuing today?

Examples from wildlife suggest that adaptation to living alongside people can continue long after animals first encounter humans.

Research led by biologist Kevin Parsons at the University of Glasgow provides one of the clearest examples of this process. In 2020, Parsons and his team compared the skulls of urban and rural red foxes from London and the surrounding countryside, and found consistent differences between the two populations.

Urban foxes had shorter, broader snouts and smaller braincases – the rounded part of the skull that encloses the brain. These are changes that often accompany domestication. The researchers suggest that city life may favour foxes that are less fearful of people and better at exploiting food and shelter provided by humans.

A similar story is emerging in Dublin’s Phoenix Park. In 2022, ecologists Laura Griffin, Simone Ciuti and colleagues at University College Dublin found that, while some fallow deer living at the edge of the city rarely came near humans, others consistently approached people for food. Around a quarter of the population were “consistent beggars”, and these bolder females produced heavier fawns – suggesting that animals willing to approach people may be at an advantage.

These studies show that living alongside humans can drive evolutionary change in wild and semi-domesticated species.

But does the same apply to cats, a species domesticated thousands of years ago? There are two possible answers. Cats may still be changing – or perhaps cats have not changed much, and it is our relationship with them that has.

Let’s start with the cats.

Compared with dogs, cats have traditionally been viewed as “less” domesticated. Dogs were bred to work alongside us – herding livestock, guarding homes and helping with hunting – while cats largely domesticated themselves.

Drawn to the rodents attracted by early farming settlements, cats chose to live near people because it suited them, not because we selectively bred them for particular jobs.

One reason cats have been so successful is their flexibility. Unlike many species, they can adjust their behaviour to suit the environment they live in.

Where food is scarce, cats tend to live alone and defend their own territory. But where food is plentiful, such as around people, they can tolerate one another and form stable social groups. In fact, some researchers suggest that cats first evolved to tolerate other cats living nearby, before extending that tolerance to humans.

Although genetics plays a role, kittens that have frequent positive interactions with humans during a critical period (between around two and seven weeks of age) are far more likely to grow into confident, friendly adults.

This suggests cats have long had the capacity to form close relationships with people when the conditions are right. Rather than becoming fundamentally different animals, they may simply be expressing a capacity they have long possessed. If so, the biggest change may not have been in cats, but in us.

People’s changing needs

Over the past century, many people’s way of life has changed significantly. Across much of the world, fertility rates have fallen dramatically, from almost five children per woman in 1950 to just over two today. People are having fewer children, delaying parenthood, living alone for longer, and increasingly relying on companion animals to meet needs once fulfilled by close family relationships.

These demographic shifts have changed not only how families are structured, but also who, or what, occupies the centre of family life.

In Finland, a country that has experienced many of these demographic shifts, a 2023 survey of 857 pet owners found that, when speaking with family and friends, people without children were more likely than parents to refer to themselves as “mom” or “dad” in relation to their pets. They were also more likely to describe their companion animals as kids, children or family members, and reported stronger emotional attachment to them.

As more people delay parenthood or remain child-free, this way of relating to companion animals may become increasingly common. This shift may also be reflected in the growing popularity of cat breeds such as the ragdoll, valued for their affectionate and docile nature.

Changing attitudes have transformed the lives cats now lead. A species once valued primarily for controlling rodents is now just as likely to have health insurance, see a behaviourist and eat a specialist diet.

None of this means cats have stopped evolving. Living alongside humans could still shape their behaviour over many generations. But the evidence suggests that the more dramatic transformation has been in their owners.

We have changed what cats mean to us and, by doing so, changed the lives they now lead. Back when I created a Facebook page for Sandi, people thought it was eccentric. Today, it seems many more people have come round to my way of thinking.

Grace Carroll does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

Larry, the Downing Street cat, has had to adapt to seven different prime ministers moving into No 10 over the past decade. Yet while the nation’s attention is fixed on the departing and incoming political leaders, who is thinking about the effect these upheavals might have on one of the property’s most enduring residents?

Cats thrive on predictability and the consistency of their environment is important for their welfare. On the whole cats prefer an unchanging environment. Some cats cope with change better than others. Many cats are distressed by disturbances such as moving house, changes in familiar routines, people moving into or leaving the household, or even changes to the scent of their home environment.

Unlike dogs, cats aren’t obligate social species, therefore may not have such a strong proclivity to form social attachments. However, in certain situations domestic cats can be found living in social groups, particularly in environments with a plentiful food supply.

Some cats enjoy the company of people, while others prefer a more solitary life. This is determined partly by their early experiences. A young kitten that learns in the early weeks of their life that contact with people is associated with nice experiences is more likely to seek social interactions with people as an adult. Kittens raised by mothers who show friendly behaviour towards people can learn to value human company through the process of social learning.

Genetics also influence a cats friendliness towards people. Researchers in a 1995 study found that the kittens of friendlier fathers were more likely to show friendly behaviour towards unfamiliar people even if they weren’t socialised as a new kitten.

Some cats appear to suffer when separated from their caregivers, although some researchers question whether this can be described as a secure attachment (one that is necessary to maintain feelings of safety and security in threatening situations).

Researchers have identified five different forms of cat-owner relationship, based on the level of emotional investment of the owner, the way the cat relates to others, their aloofness and their need to be in close proximity to their owner. These types range from open relationships (characterised by a lightly emotionally invested owner and an avoidant cat) to casual relationships, co-dependence and friendship.

Although the Starmer family has moved out and the Burnhams have taken up residence, Larry’s main caretakers are civil servants, so his day-to-day care won’t change. Larry’s behaviour in recent days (strutting along Downing Street, nonplussed by the comings and goings and embarking on a successful hunting expedition) suggests that he takes such changes in cohabitants in his stride.

Other animals

The new prime minister has a dog called Axel, and although cats and dogs can live together harmoniously and even form close bonds, integrating Axel into Larry’s home might cause tensions if not handled well. However, not even the prime minster would dare to disturb Larry’s position as chief mouser. Andy Burnham has told the BBC he’s not bringing Axel to London with him because he doesn’t think the two animals will get on.

If he changes his mind there are a few things he could do to help Axel and Larry get along. Introducing a dog into a household with a cat should be done gradually, with the aim to prevent any chasing or aggression between the pets.

Before the dog arrives, settle the cat into a safe space, which the dog won’t have access to. This might be a bedroom, bathroom or any part of the house that the cat likes to relax in, ensuring the cat has access to everything they need such as places to hide, litter trays, food and water.

Scent is incredibly important to both cats and dogs, so getting them accustomed to each other’s aroma in the home helps to smooth the introduction. This can be done by introducing bedding or toys used by the other pet, or gently wiping a damp cloth across the body of the pet to pick up their scent.

It’s vital that the first meeting goes well and there are a few things that will help to ensure they get off on the right foot. Make sure the dog isn’t full of energy by exercising them before the meeting. Start with a barrier such as a baby gate between them.

When they first meet give both pets plenty of their favourite food treats, to reward calm behaviour and so that they associate the presence of other with something nice happening.

Signs of stress

Cats can be difficult to read but there are known warning signs of stress in cats. More obvious stress behaviour includes hissing, growling, swiping or puffed up fur. But indicators also include the cat running away or hiding and refusing treats they normally avoid. Flattened ears, dilated pupils, tense body posture and a flicking tail are all signals a cat is feeling tense.

Larry seems like quite an independent confident cat if reports “he has the run of the house” are anything to go by, so it’s likely that he will soon teach the new inhabitants of No 10 how he likes things done.

Emily Blackwell does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.