Cat tales

Our relationship with our pets has a very long history.

We know more about our connection to dogs; we've been keeping dogs (or vice versa) for at least ten thousand years, based on genetic analysis of bones found in proximity to human settlements -- and often, buried with honor.  How this relationship started is a matter of conjecture:

Wolf: I'm going to attack you, and viciously tear apart and eat your children!  You are no match for my ferocity!

Cave man: We have peanut butter, sofas, and squeaky toys.

Wolf:  ... I'm listening

Domestic cats, on the other hand, have more uncertain origins.  They were known to have been revered in ancient Egypt, and in fact the much-loved protector goddess Bastet is always depicted with a cat's head.  The ancestors of today's house cats are thought to be the Libyan wildcat (Felis lybica), a small felid which is still found in most of Africa, the Middle East, and central and southern Asia.  They were probably encouraged to live alongside humans for their use as mousers, and eventually became companion animals, just as dogs had earlier.

What's certain is that after that relationship formed, wherever humans went, their pets came along.  A very cool series of studies a while back used patterns of cat genetics -- in particular, the prevalence of the polydactyly gene and the gene that controls swirled tabby coat coloration -- to figure out the paths of migration taken by their human owners.  And just this week a fascinating paper appeared in the journal Science looking at how domestic cats first arrived in China, much more recently than you might think.

The first written reference to cats in China comes from the Tang Dynasty, and dates to the middle of the seventh century C.E.  It's a rather horrifying story.  An imperial concubine name Xiao ran afoul of a higher-ranked wife named Wu Zetian (Wu eventually was to become empress outright).  Wu had Xiao condemned to death -- by having her hands and feet chopped off, then to be drowned in a barrel of wine -- and before the sentence was carried out, Xiao said, "In my next life, may I be reborn as a cat, and Wu Zetian as a mouse.  I will then seize her by the throat to extract my revenge!"

Wu wasn't impressed, and had her rival executed anyhow.  History doesn't record any subsequent rebirths as cats and/or mice.

The earliest domestic cat bones found in China are from an archaeological site called Tongwancheng, and date to only around 1000 C.E.  There were earlier feline specimens, but they all seem to be the remains not of modern domestic cats but of the leopard cat (Prionailurus bengalensis), a small south Asian wildcat species (that recently was crossbred with the domestic cat to produce the Bengal breed), and which probably lived alongside humans but was never truly domesticated.

Bengal cat [Image licensed under the Creative Commons User:Lightburst, Paintedcats Red Star standing, CC BY-SA 4.0]

As far as domestic cats, they seem to have arrived in China via the Silk Road.  Bones found in Kazakhstan, dating to the ninth century C.E., have a mitochondrial DNA signature that links both to later Chinese cats and to cats in the Middle East -- suggesting that merchant travel between the two is how cats arrived in east Asia.

Once there, they established a place in Chinese culture as the favorite pet of the wealthy.  Like the earlier study of cat genes and human migration, this one has an odd filigree having to do with how human selection influences evolution.  In Chinese culture, white is a symbol of purity, and white animals are especially revered.  This gave Silk Road merchants an incentive to find and transport white cats -- a practice over a thousand years ago which has left its mark all these centuries later.  This selectivity of importation is probably why today a disproportionate number of modern Chinese cats are white (or have white patches).

So we move, and we take our pets with us, and that changes both them and us.  It's a very old connection, and one many of us cherish deeply.  Think of that next time you cuddle with your kitty or puppy -- you're taking part in a relationship that goes back thousands of years, and was important enough even in those rough times that it drove commerce.  So even before the existence of mail-order places like Chewy, where we can spend inordinate amounts of money pampering our furry friends, our bonds with our pets were still a deeply important part of our lives.

****************************************

Dog tales

People who know me are well aware that I consider our two dogs, Guinness and Cleo, to be family members, not just pets.

They're kind of an odd couple.  Guinness ("Dorkus Maximus") is a big, lumbering pit bull mix, whose thick coat and curly tail comes from some husky and chow ancestry turned up by DNA analysis; Cleo ("Dorkus Minimus") is a tiny, one-eyed pure-bred Shiba Inu rescue, whose personality supports the contention that Shibas are dogs for people who really wanted a cat instead.  Despite the fact that they seem to have nothing in common, they are best friends.  When they play tug-of-war, even though Guinness outweighs Cleo by a factor of four, he lets her win sometimes, as a good big brother should.

I've dealt here before with the fascinating questions surrounding how dogs were domesticated, and how since then they've coevolved to live with (i.e. manipulate) their owners.  So it was no surprise that a recent piece of research in the journal Anthropozoologica caught my eye.  The author, Julian d'Huy of the Collège de France, has been studying the mythology that has grown up around dogs in cultures across the world, and found some fascinating commonalities -- suggesting that our mythologizing dogs has as long a history as our domesticating them.

d'Huy found that there were three themes that seemed to be universal: (1) dogs as faithful companions to heros/heroines; (2) dogs as protector spirits and guides to the afterlife; and (3) an association between dogs and the star Sirius (the "Dog Star," the brightest star in the night sky, in the constellation Canis Major -- the "Big Dog").  

The first one is hardly surprising, given the fact that humans have had dogs as companion animals for thousands of years.  The second I find a little more puzzling.  Neither of our dogs is what you might call an effective guard dog, unless you count their mortal hatred of the Evil UPS Guy.  When the Evil UPS Guy shows up, both Guinness and Cleo go berserk, running around and barking, Guinness's booming "WOOF" punctuated by Cleo's comical and high-pitched "Ruff!", until finally the Guy gets scared and intimidated and leaves.  At least that's how they interpret it.  What seems to go through their heads is "we barked and he ran away, go us!"  Then they high-five and go back to sleep, so worn out that they wouldn't even twitch if an actual burglar were to show up.  In fact, if the burglar had some chunks of cheese in his pocket, Cleo would probably show him where the valuables are hidden.

I do think it's kind of fascinating, though, despite my own dogs' failings in the Guardian of House and Hearth department, that so many cultures associate dogs with being protector spirits, many of them shapeshifters who were thought to continue their loyal defense even in the afterlife.  Part of the elaborate tattoo on my back, shoulder, chest, and arm contains a design of two Celtic-style dogs, a tribute not only to my personal furry friends but to their role as spiritual guides and protectors.

But the oddest of all is the third of d'Huy's observations -- that apparently, Sirius was associated with dogs by more cultures than just the ancient Greeks.  Given the dubious resemblance of the constellations to the things they're supposed to represent, I always figured that most of them were completely arbitrary, and our current designations were probably the result of some ancient Greek guy looking up into the night sky at a random cluster of stars, probably after drinking way too much ouzo, and saying, "Hey, y'ever notice that bunch o' stars over there?  Looks just like a dude pouring water out of a pitcher."  And that's how "Aquarius" was born.

d'Huy's contention is that the association of Sirius with dogs isn't because there's anything especially doggy about it, but that the connection goes way back -- so much so that it's been passed down in many different cultures, and maintained even as populations traveled all over the world.  I don't know how you'd prove such an assertion, but in any case, it's kind of a strange coincidence otherwise. 

So dogs have worked their way not only into our hearts and homes, but into our stories, lore, and mythology.  I guess it only makes sense that these creatures who have become so close to us would show up in the tales we tell.  Dogs have made appearances in my own books, most notably the characters of Ahab (in Signal to Noise) and Baxter (in Kill Switch), the latter of which was the cause of one of the funniest interactions I've ever had with a reader.  I was walking down the street in my home village, and a guy I barely know came up to me and said he was reading Kill Switch, and so far, enjoying it.

"I just wanted to let you know one thing, though," he said.  "I know it's a thriller.  I know people are gonna die.  But..." -- and here, he grabbed me by the arm and looked me straight in the eye with a grim expression -- "... if you kill Baxter, I will never speak to you again."

We care deeply about our pets, even fictional ones, I guess.

But now I need to wind this up, and go see why Guinness and Cleo are barking.  My guess is it's the Evil UPS Guy again.  He just never gives up, that Guy.

****************************************

Talking to the animals

We just got back from a week-long trip to visit friends in Seattle, which meant boarding our two dogs with a local kennel.  We know and trust them -- we've used them for years -- and they love our dogs, quirks and all.  So we can leave them and be sure that they're in good hands.

Guinness, for the most part, has no problem with kenneling.  He knows he's going to get treats and play time, so for him it's kind of like sleep-away summer camp.  He jumps right into the car like it's going to be a great big adventure.

Cleo, on the other hand.

Our little Shiba Inu rescue was caged during much of her four years with an abusive breeder, and she has an absolute terror of being locked up.  She's relaxed considerably since we got her in December of 2021 -- especially once we installed a dog door so she can go in and out of our big fenced back yard whenever she wants -- but she still freaks out when the door closes behind her.  And she gets very, very wary when she knows we're going to pick her up and put her in the car (for example, on trips to the vet).  She's really snuggly and friendly if it's on her terms -- but if she knows she's going to be restrained, good freakin' luck.

Cleo in a calm moment

So we've tried everything we can think of to (1) lower the stress surrounding the situation, and (2) make it easier to get her when we absolutely have to.  Bribing her with food barely works; she's the least food-motivated dog I've ever met.  Calm talk has zero effect.  And my wife pointed out to me that my tightly-wound personality comes through in my voice, that if I say in as friendly and non-threatening a manner as I can, "Hey, Cleo, c'm'ere!  Want some cheese?" she not only isn't gonna respond to the bribe, she knows that I'm up to something.

I've tried whatever I can, but I don't seem to be able to help having it show when I'm anxious about something, like when we have to drop the dogs off at the kennel by 9 AM, and it's 8:45, and we're chasing Cleo all around the back yard.  At first, I was a little reluctant to believe that Cleo is really that sensitive to subtleties in my tone of voice, but after a few frustrating hour-long battles to come closer to her than ten feet, I have to admit Carol's got a point.

And some research out of the University of Copenhagen that appeared last week in the journal BMC - Biology bears out her contention that domestic animals are way better at picking up on vocal tone than anyone thought.  It's an odd claim, when you think about it; why should domesticated animals -- even ones like dogs, who have been in association with humans for tens of thousands of years -- recognize human social signals?  Even between closely-related primate species, the same signal can mean entirely different things.  For example, smiling is a sign of friendliness amongst humans, but smiling to a chimp is basically baring the teeth, and is considered an indicator of aggression or fear.

But the research seems unequivocal.  And they weren't even working with dogs; they primarily worked with pigs and horses.  They even controlled for the possibility that animals might learn certain words and have associations (positive or negative) that come along with them, something that is certainly true of most dogs.  (Say "do you want to play fetch?" to Guinness and he immediately turns into the canine ping-pong ball.)  What the researchers did was to hire a trained actor and gave him various gibberish phrases, with the instruction to speak them in a variety of differing tones.  They then recorded the animals' reactions on a lot of benchmarks -- ear position, facial tension, pupil dilation, and so on.

The animals had no problem picking up on the actor's emotional tone.  "Our results show that these animals are affected by the emotions we charge our voices with when we speak to or are around them," said Elodie Briefer, who co-authored the study.  "They react more strongly -- generally faster -- when they are met with a negatively charged voice, compared to having a positively charged voice played to them first.  In certain situations, they even seem to mirror the emotion to which they are exposed."

So Carol, apparently, is spot-on about Cleo picking up the tension in my voice.  The open question is what I can do about it.  Even when I'm aware of it and trying to moderate it, it apparently comes through loud and clear.  At least this is the last time for a while that we're going to kennel them, she doesn't have any upcoming vet appointments, and maybe just time and trust-building will convince her that whatever happens, she's safe.

**************************************

Doggie determination

Our dog Guinness has brought home the truth of the quip that cats are teenagers, dogs are toddlers.

His engine has two settings: "full throttle" and "off."  We got him two and a half years ago as an eleven-month-old rescue, so he has settled down a little as compared to the irrepressible puppy exuberance he came with.  Which is a bit of a relief.  Handling seventy pounds' worth of irrepressible puppy exuberance can be a little exhausting.

He is never content unless he's interacting with either me or my wife.  "Will you please go entertain yourself for a while?" is a common phrase heard around Chez Bloomgarden-Bonnet.  And he doesn't just want to interact with us any old way; it has to be exactly the right way.  He loves to play fetch -- can do so for hours on end -- but not if we're standing on the patio.  No, throwing the ball into the lawn from the patio is not the proper way.  A true game of fetch must be played from a seated position, in one of the lawn chairs next to the pond.  I kid you not.  From the patio, he'll chase the ball once, pick it up, and then stare at us with an expression like, "What the hell am I supposed to do with this?"  Move a hundred yards in a westward direction to the lawn chairs by the pond, and he will happily retrieve over and over.  And over and over and over.

No, I don't get it, either.

Be that as it may, he is extraordinarily sensitive to our moods, tone of voice, and body language, and seems to watch us constantly for cues about what is going on.  We can talk about him without using any obvious clue-words like his name, or even dog or play or ball, and he immediately knows (to judge by the fact that his tail will start wagging, even if he appeared to be sound asleep).  When we talk to him directly, he stares at us with this eager expression, like he really wants to understand every word we're saying.  If it's a bit above his head, he gives us the Canine Head-Tilt of Puzzlement:

"I'm so disappointed in myself," he seems to be saying.  "I will try much harder to understand next time."

You might even say he shows dogged determination.  *rimshot*

He's also one of the most affectionate dogs I've ever known.  Like I said, his number one priority is interacting with us as much as possible.

The reason all this comes up is because of a study that appeared this week in the journal Current Biology that strongly suggests dogs come pre-wired to connect with humans -- i.e., this isn't learned behavior.  Dogs may refine these skills, and learn specific cues and behaviors, but the ability is innate.

Led by Hannah Salomons of Duke University, this study compared the behavior of puppies and wolf cubs, both groups of which had been given equal prior exposure to humans.  They found that the puppies automatically responded to people -- they were much more willing to come up to a person spontaneously, make eye contact, and look to the human for cues about what to do.  Wolves, on the other hand, started out afraid, and would huddle in the corner when a person came close, and even once habituated to people's presence would mostly ignore them rather than interact.  "They acted like I was a piece of furniture," Salomons said.

Most fascinating of all, puppies seem to come equipped with at least some level of a "theory of mind" -- knowledge that their own perspective isn't shared by everyone, and that the world would look different through the eyes of another.  One of the most rudimentary theory-of-mind tests is to point at a treat on the floor that is visually hidden from the dog -- i.e., you can see it, the dog can't.  Wolves don't respond to this at all; dogs usually pick up on it right away.  And it's a more sophisticated response than it seems at first.  To figure out what pointing means, the dog has to think, "If I was standing where (s)he is, sight-lining down the arm toward the floor, where would it be indicating?"

"Dogs are born with this innate ability to understand that we're communicating with them and we're trying to cooperate with them," Salomons said, in an interview with Science Daily.

We not only cooperate with them, we also provide a valuable opportunity for them to get dressed up fancy now and again.

It seems like this in-touchness dogs are born with has come from millennia of domestication, where their use as companions meant that generation after generation people were selecting the most responsive, interactive dogs, meaning their capacity for bonding to humans increased over time.  Contrast that to cats -- and I mean no disparagement of our feline friends -- but they are often characterized as more aloof and self-reliant than dogs.  No surprise, really; having cats as companion animals is a relatively recent innovation, while there is good evidence that dogs have been companions back at least thirty thousand years.

"This study really solidifies the evidence that the social genius of dogs is a product of domestication," said Brian Hare, professor of evolutionary anthropology at Duke, senior author of the study.  "It's this ability that makes dogs such great service animals.  It is something they are really born prepared to do."

Now, y'all'll have to excuse me.  Guinness wants something.  I'm not sure if it's food, petting, or an early round of fetch-the-ball.  Maybe some of each.  Don't worry, I'll figure it out.

Which, incidentally, brings up the awkward question of who domesticated whom.

**************************************

I've loved Neil de Grasse Tyson's brilliant podcast StarTalk for some time.  Tyson's ability to take complex and abstruse theories from astrophysics and make them accessible to the layperson is legendary, as is his animation and sense of humor.

If you've enjoyed it as well, this week's Skeptophilia book-of-the-week is a must-read.  In Cosmic Queries: StarTalk's Guide to Who We Are, How We Got Here, and Where We're Going, Tyson teams up with science writer James Trefil to consider some of the deepest questions there are -- how life on Earth originated, whether it's likely there's life on other planets, whether any life that's out there might be expected to be intelligent, and what the study of physics tells us about the nature of matter, time, and energy.

Just released three months ago, Cosmic Queries will give you the absolute cutting edge of science -- where the questions stand right now.  In a fast-moving scientific world, where books that are five years old are often out-of-date, this fascinating analysis will catch you up to where the scientists stand today, and give you a vision into where we might be headed.  If you're a science aficionado, you need to read this book.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Cat tales

Humans have been keeping pets for a very long time.

A lot of it now is companionship, and I have to admit that despite Guinness having to play fetch-the-tennis-ball for several hours a day so he runs off enough energy that he won't get fidgety and eat the sofa, he's kind of entertaining to have around.  The thought is that dogs probably began the human/canine relationship as fierce and loyal guardians of home and hearth, and from there moved into closer emotional links, ultimately giving rise to phenomena like pugs wearing knitted sweaters with matching stocking caps.

Cats, on the other hand, aren't much good at home security, and at first were most likely kept around as mousers.  It must be said, however, that all of the cats I've owned were kind of non-starters as mousers.  They mostly specialized at sitting around looking bored, only moving when the block of sunshine they were occupying had the nerve to go somewhere else.  In my experience, they were more like dubiously-useful home décor items that pooped in a box in the laundry room.

Still, the human/feline association goes back a long way as well.  Back in 2017 a study at the Jacques Monod Institute in Paris used mitochondrial DNA from both ancient cat skeletons and modern cats to show that people were bringing cats with them when they migrated as long ago as 4,500 B.C.E.  The researchers used the frequency of the "blotched tabby" allele -- a gene that causes cats to have swirls of color in their coats instead of parallel stripes -- followed human migration patterns throughout the Middle East and Europe, making cat genetics a useful tool in determining where their human owners traveled.

[Image licensed under the Creative Commons Helgi Halldórsson from Reykjavík, Iceland, Cute cat (1698598876), CC BY-SA 2.0]

This wasn't the first study to connect cat genetics with human migration.  All the way back in 1977, an article in Scientific American by Neil Todd showed that the polydactyly gene -- which gives cats six toes per foot -- jumped from colonial New England to Nova Scotia and New Brunswick after the British lost the Revolutionary War.  A lot of Loyalists went to Canada and apparently brought their six-toed cats with them, creating pockets of high frequency of that allele in areas where the Loyalists ended up.

In 2005 a study appeared in the Journal of Heredity that created a family tree for 32 different cat populations, focusing particularly on cats in Arkansas and Tennessee, and found that the genetics of domestic cats was consistent with the genetics of whoever settled the area -- that places predominantly settled by people of Scottish descent, for example, still today have cats that are more closely related to their Scottish cousins than to cats in France or Switzerland.  It's kind of fascinating to think that our kitties here in the United States have their own migration patterns, from the Middle East to Europe to America, and that the routes they took are the same ones followed by their human owners.

The reason all this comes up is a study that showed up this week in Nature Scientific Reports called "The Earliest Domestic Cat on the Silk Road," by a team led by A. F. Haruda of the University of Exeter.  In it we find that pet cats -- not just practical semi-feral barn cats -- were being kept by Kazakh pastoralists a thousand years ago.

The authors write:

We present the earliest evidence for domestic cat (Felis catus L., 1758) from Kazakhstan, found as a well preserved skeleton with extensive osteological pathologies dating to 775–940 cal CE from the early medieval city of Dzhankent, Kazakhstan.  This urban settlement was located on the intersection of the northern Silk Road route which linked the cities of Khorezm in the south to the trading settlements in the Volga region to the north and was known in the tenth century CE as the capital of the nomad Oghuz.  The presence of this domestic cat, presented here as an osteobiography using a combination of zooarchaeological, genetic, and isotopic data, provides proxy evidence for a fundamental shift in the nature of human-animal relationships within a previously pastoral region.  This illustrates the broader social, cultural, and economic changes occurring within the context of rapid urbanisation during the early medieval period along the Silk Road.

The study looked at an amazingly complete cat skeleton that was buried beside a trade route.  What was remarkable was that the cat had apparently had a rough life -- it had several broken bones -- but those bones had healed, meaning it had been cared for post-injury.  Isotopic analysis of its bones showed that it had a very high protein diet, suggesting it was fed by humans rather than foraging on its own.  Toward the end of its life, it lost most of its teeth, so the fact that its diet remained good throughout is a pretty good indicator that someone was caring for it as a prized pet.

We often associate reverence for cats with the ancient Egyptians, but it's clear they weren't the only ones who held our feline friends in high regard.  We've been fond of our companion animals for a very long time, and wherever we go, they do.

Which I think is pretty sweet.  Even if they're only useful as décor.

***********************************

This week's Skeptophilia book of the week is for anyone fascinated with astronomy and the possibility of extraterrestrial life: The Sirens of Mars: Searching for Life on Another World, by Sarah Stewart Johnson.

Johnson is a planetary scientist at Georgetown University, and is also a hell of a writer.  In this book, she describes her personal path to becoming a respected scientist, and the broader search for life on Mars -- starting with simulations in the most hostile environments on Earth, such as the dry valleys of central Antarctica and the salt flats of Australia, and eventually leading to analysis of data from the Mars rovers, looking for any trace of living things past or present.

It's a beautifully-told story, and the whole endeavor is tremendously exciting.  If, like me, you look up at the night sky with awe, and wonder if there's anyone up there looking back your way, then Johnson's book should be on your reading list.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Dog days

My wife and I share our living space with two canine companions.

First, we have Grendel, a (very) mixed breed, who looks like the result of blenderizing DNA from a pug, a German shepherd, a pit bull, a husky, and a fireplug.  He's cute, in a melancholy, "what are you so sad about, boy?" kind of way, and uses his wide range of pathetic expressions to get attention and food scraps.

Then we have Lena, whose ancestry includes redbone, blue-tick coonhound, and beagle.  She's eternally cheerful, has a tail that never stops wagging, lives for chasing squirrels, and has the intelligence of a loaf of bread.

They get along pretty well, although I kind of get the impression they don't really understand each other.  Grendel sometimes tries to play with Lena, in his ponderous sort of way, but it never lasts very long.  Lena usually ends up capering around, trying to fit all of the toys in her mouth at the same time, and Grendel gives up, sighs heavily, and plods over to us hoping we'll give him a dog cookie for at least giving it a shot.

I've always had dogs.  There's something about having a dog in my house that just seems necessary.  It always comes along with bushels of pet hair, muddy pawprints, and a variety of carpet stains, but I can't imagine that part of my life being missing.

I bring all of this up because I've always wondered about how dogs were domesticated.  Some people think they started out as utilitarian hunting animals, and after selection for responsiveness to human interaction, gradually morphed into what we have today.  Others think that the companionship aspect was there from the beginning, perhaps from as long ago as our cave-dwelling days.

The question, of course, will probably never have much going for it other than speculation, given that we don't have much in the way of evidence on which to base an answer.  However, a study by Laurent Frantz of Oxford University et al., published this week in Science, has at least given us a little more information about when and where this pivotal event took place.

According to Frantz's team, a study of DNA from the remains of 59 ancient dogs, including one from the late Neolithic Period (this particular mutt lived in Newgrange, Ireland about 4,800 years ago), dogs were domesticated at least twice -- once in Western Europe, and once in East Asia.  The East Asian dogs came with their human friends during migrations, and interbred with preexisting European Paleolithic dogs to produce most of the breeds familiar in Europe and America.  Says Tina Hesman Saey, who wrote about the study in Science News:

Using the Newgrange dog as a calibrator and the modern dogs to determine how much dogs have changed genetically in the past 4,800 years, Frantz and colleagues determined that dogs’ mutation rate is slower than researchers have previously calculated.  Then, using the slower mutation rate to calculate when dogs became distinct from wolves, the researchers found that separate branches of the canine family tree formed between 20,000 and 60,000 years ago.  Many previous calculations put the split between about 13,000 and about 30,000 years ago, but the new dates are consistent with figures from a study of an ancient wolf’s DNA.

Which is a long time ago, considering that most of the distinct modern dog breeds trace back to a common ancestor only a few centuries ago.  (Exceptions include some of the old Chinese breeds, such as the Pekingese, Shih-Tzu and Sharpei, which seem to be a good bit older than that.)  But despite the recent diversification of shapes, sizes, colors, and behaviors, what seems pretty certain is that dogs in some form have been our friends for a long, long time.

Compare this to cats.  A recent study done in Japan found that cats recognize their own names and their owners' voices, but apparently evolved not to give a damn.  Their ears turn and whiskers twitch when their owners speak, but it doesn't make a lot of difference to their behavior otherwise.  I find this result unsurprising.  I can say from personal experience that my 18-year-old cat Geronimo considers me to be warm-blooded furniture, and his expression usually says, "I am only refraining from clawing your eyes out because you feed me expensive canned food every day."  Contrast this to Lena, whose body language communicates "I LOVE YOU SOOOO MUCH" if I give her a muddy stick to chew on.

Not that I'm biased, or anything.  I'm sure that a lot of this is my projecting my own emotions, thoughts, and feelings onto my pets, but when Grendel looks up at me with those big sad eyes, it's hard not to sense a bond.  Maybe we've evolved into the relationship, too, because there's something primal and comforting about having a dog around.

Despite the hair, muddy pawprints, and carpet stains.