Cat owners often remark that surviving cats seem to take on the personality and habits of a recently deceased feline companion. There is, of course, nothing supernatural in this. The surviving cat is simply taking over the vacated territory and privileges.

"Since Tiddles died, Tabby has started sitting in all his favourite places," says Mrs Cat-Owner.

In other words, the more dominant Tiddles had staked a territorial claim to the best places and Tabby had to wait for Tiddles to expire before annexing them to her territory. It's "dead-cat's sunbeams" - the feline equivalent of "dead man's shoes" in some careers (you only get promoted when someone higher up the ladder dies or leaves).

"Since Fluffy died, Snuffy is much more outgoing," she says.

Which translates as "since Fluffy went, that young upstart Snuffy can do things without getting his nose biffed". The same would have happened if Fluffy had moved home or had a debilitating illness. Household territories and privileges change as cats grow older, weaker or stronger.

All this common sense doesn't explain why Thenie, who installed herself a few years ago, has adopted the behavioural quirks of several long-dead feline residents of the household. Maybe former residents, not content to haunt me invisibly, have been reincarnated as a composite being in a single fluffy black body to intervene directly in my life. As a mere human, I can't be trusted to run things myself and the combined spirits of feline past don't trust one of those new fangled modern cats (don't know they're born, never done a day's hunting in their lives) to run a household. Maybe Thenie channels the former inhabitants of the household. If so, she changes channels to keep me on my toes.

The other day she was evidently channelling Kitty I when she waltzed up to a small white dog and subdued it.

"That's an odd cat," said Sweetiepup's owner, as Thenie approached the cat-friendly and well-mannered mongrel, tail held high.

Thenie and the quivering dog sniffed noses. Thenie's tail was up. The dog's stumpy tail wagged tentatively. The dog was slightly smaller than Thenie.

"She likes dogs," I said, fractionally before Thenie thumped the unsuspecting canine, ".... After she's shown them who's boss."

Smirking, as only a cat can smirk after pulling the rug from under its owner's feet, Thenie sprayed the hedge with the attitude of a cat after a job well done. I only just managed to hop out of the way.

I know Thenie likes dogs because she often comes home smelling of dog. I've seen her sneaking into a neighbour's garden where she has subdued a much larger dog and sleeps on it. Or possibly she evicts it from its kennel and sleeps in there. I can't be certain of the sleeping arrangements, but the end result is a cat that smells strongly of Labrador. Dog-taming was once the hobby of Kitty I.

When Thenie moved in, it was like having a mix of black Scrapper and fluffy ginger Affy rolled into one fluffy black body. Long-dead Affy's favourite haunts, ignored by Motley and Cindy, became Thenie's favourite haunts (I'll chalk this one down to staking out prime snoozing territory). Like Scrapper, she came when whistled and slept wrapped round my head on the pillow. It's only when the dog-hunting began that I suspected my original triumvirate of Kitty I, Scrapper and Affy had all come back to haunt me.

Now the weather is fine, she enjoys a picnic on the back doorstep. There's a fresh bowl of food in the kitchen and the back door is often open so we can both go in and out, but picnics are obviously de rigeur. After all, it's not as far to walk when she's snoozing on the patio or the garage roof. Sappho used to insist on eating al fresco in summer and this meant pushing the bowl through the cat flap before I went to work. Evidently Sappho is also sending some food-related messages from the great cat bed in the sky.

"It's Whiskas Oh So Fishy," I'd say, putting the bowl on the kitchen floor.

Thenie would sniff it suspiciously and ignore it.

"You like Oh So Fishy," I'd insist, on the dubious grounds she'd eaten it the previous day (this means nothing of course, in an extension of the Schrodinger's Cat effect, cats are perfectly capable of simultaneously loving and hating a particular food until they are observed as being in one state of mind or the other).

Thenie would move to the cat flap then sit outdoors peering in.

"Oh, okay then," I'd say, placing her bowl on the back step whereupon she hoovers the entire contents up in under 5 minutes.

This is an almost exact replay of the Sappho "al fresco" phenomenon of several years ago, the main difference being that the face peering through the cat flap lacks white markings.

Then Thenie has discovered the garage roof, This was Motley's favourite snoozing place and offers unparalleled views of 2 streets and a variety of human and animal life (cats, dogs, foxes, pigeons and schoolkids). She also annexed a branch of the big hawthorn tree where she sleeps with tail and paw dangling like a small, fluffy black panther. When she comes in, she has a light dusting of green algae that I really out to photograph as being the only extant example of a real life green kitty.

Logic tells me this sole feline occupant is simply exploiting all the territories and privileges previously divided among feline duos and trios. My current lifestyle and her personality means no additional cats while she's the boss. It wasn't always that way. When Thenie first moved in she was deferential to residents Motley and Cindy. Cindy died during emergency surgery and Motley succumbed to a brain tumour, but quite frankly I wouldn't put it past Thenie to have laced their Kit-E-Kat in order to hasten the succession. Woe betide any misguided moggy that ventures into the garden or, worse, through the cat flap (sitting outside a pinned open cat flap, yelling and swiping at an intruder who is inside and desperately wants out was not one of her brightest ideas).

Apart from former residents Motley and Cindy, the only cat to have escaped the Wrath of Thenie was deaf, senile, permanently hungry Penny who took to popping in for snacks during her last few months. Too deaf to hear Thenie swearing at her and too senile to react to being swiped, ancient tabby Penny just carried on eating any food she came across. If it happened to rain when she was raiding my trio's bowls, Penny simply crashed out on the sofa until the rain stopped or I found her and carried her back to her owners. Motley and Cindy just shrugged and ignored the slightly whiffy old cat as long as she didn't try to sleep on their chairs. After doing the full swearing and posturing stuff, Thenie simply found it too much effort to evict Penny. In the ongoing game of dead cat's sunbeams, it was much less effort to wait for ancient Penny to succumb to the inevitable.

Footnote: I'm well aware I'm not the only one with a composite kitty. My friend and former colleague Doug has a torbie-and-white called Nutmeg who seems to have multiple personality disorder. He insists she's three-cats-in-one - a tabby that has been shunted by a white cat and then rebuilt using bits from a red cat, a bit like a "ringed" car.