Cats in boxes

Any cat owners amongst my readers will undoubtedly know about the strange propensity of cats to climb into boxes.  Apparently it works for cats of all sizes:

With apologies to Robert Burns, a cat's a cat for a' that.

In fact, it doesn't even have to be a real box:

I've never heard a particularly convincing explanation of why cats do this.  Some people suggest it's because being in close quarters gives them a sense of security, perhaps a remnant of when they lived in the wild and slept in burrows or caves.  Me, I suspect it's just because cats are a little weird.  I've been of this opinion ever since owning a very strange cat named Puck, who used to sleep on the arm of the couch with one front and one back leg hanging limp on one side of the arm and the other two dangling over the other side, a pose that earned her the nickname "Monorail Cat."  She also had eyes that didn't quite line up, and a broken fang that caused her tongue to stick out of one side of her mouth.  She was quite a sweet-natured cat, really, but even people who love cats thought Puck looked like she had a screw loose.

The topic comes up because of a delightful piece of research in the journal Applied Animal Behaviour Science.  The paper was titled "If I Fits, I Sits: A Citizen Science Investigation into Illusory Contour Susceptibility in Domestic Cats," by Gabriella Smith and Sarah-Elizabeth Byosiere (of Hunter College) and Philippe Chouinard (of LaTrobe University), and looked at data collected from cat owners to find out if cats are fooled by the Kanizsa Rectangle Illusion.

The Kanizsa Rectangle Illusion is an image that tricks the brains into seeing contours that aren't there.  Here's one representation of it:

To most people, this looks like an opaque white rectangle laid over four black hexagons, and not what it really is -- four black hexagons with triangular wedges cut out.  Apparently the brain goes with an Ockham's Razor-ish approach to interpreting what it sees, deducing that a white rectangle on top of black hexagons is much more likely than having the cut-out bits just happening to line up perfectly.  It's amazing, though, how quickly this decision is made; we don't go through a back-and-forth "is it this, or is it that?"; the illusion is instantaneous, and so convincing that many of us can almost see the entire boundary of the rectangle even though there's nothing there.

Well, apparently, so can cats.  And, as one would expect, they sit in the middle of the nonexistent rectangle just as if it was a real box.  The authors write:

A well-known phenomenon to cat owners is the tendency of their cats to sit in enclosed spaces such as boxes, laundry baskets, and even shape outlines taped on the floor.  This investigative study asks whether domestic cats (Felis silvestris catus) are also susceptible to sitting in enclosures that are illusory in nature, utilizing cats’ attraction to box-like spaces to assess their perception of the Kanizsa square visual illusion...  [T]his study randomly assigned citizen science participants booklets of six randomized, counterbalanced daily stimuli to print out, prepare, and place on the floor in pairs.  Owners observed and videorecorded their cats’ behavior with the stimuli and reported findings from home over the course of the six daily trials...  This study revealed that cats selected the Kanizsa illusion just as often as the square and more often than the control, indicating that domestic cats may treat the subjective Kanizsa contours as they do real contours.

It's a fascinating result, and indicative that other animal species see the world much as we do.  It still doesn't explain why cats like to sit in boxes, though.  I think my conclusion ("cats are weird") covers it about as well as anything.  But at least in one way, our perceptual/interpretive centers are just as weird as the cats' are.  I'm not inclined to go sit in a box, but it does make me wonder what our pets would think if we showed them other optical illusions.

I doubt my dogs would be interested.  If what they're looking at has nothing to do with food, petting, napping, or playing, they pretty much ignore it.  Must be nice to see the world in such simple terms.

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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.

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Grieving

I've always been an animal lover.  I grew up with dogs, and have had one or more dogs or cats all of my adult life.  Add to that a near-fanatical passion for birding, and a general fascination with wildlife of all sorts, and it's no wonder I went into biology.

My background in evolutionary genetics has driven home the point that humans aren't as different from the rest of the animal world as a lot of us seem to think.  The false distinction between "human" and "animal" is a pretty hard one to overcome, however, which explains the argument I got into with a professor at the University of Washington over a mouse he'd killed for experimental purposes when I was in an animal physiology class.

Even back then, I understood that non-human animals die for experimental purposes all the time.  Despite my youth, I had thought deeply about the ethical conundrum of sacrificing the lives of our fellow animals for the benefit of science and medicine, and had come to the conclusion (an opinion I still hold) that it is a necessary evil.  But what I could not stomach was the professor's cavalier attitude toward the life he'd just taken -- joking around, acting as if the little warm body he held in his hand had been nothing but a mobile lump of clay, worthy of no respect.

"It's not like animals have feelings," I recall his saying to me, with a faint sneer.  "If you spend your time anthropomorphizing animals, you'll never make it in this profession."

I remembered, while he was lecturing me in a patronizing fashion about my soft-heartedness, pets I had owned, and I had a momentary surge of self-doubt.  Was he right?  I began to question my own sense that my dogs and cats loved me, and were feeling something of the same kind of bond toward me that I felt toward them.  Is my puppy's wagging tail when I talk to him nothing more than what C. S. Lewis called a "cupboard love" -- merely a response that he knows will get him fed and petted and played with, and a warm place to sleep?

But I couldn't bring myself to believe that forty years ago, and I don't believe it now.  I have several times gone through the inevitable tragedy of losing beloved pets, and what has struck me each time is not only how I and my wife have reacted, but how our other animals have.  Most recently, when our sweet, quirky little one-eyed Shiba Inu, Cleo, somehow got out of our fence and was hit and killed by a passing car, our big old pit bull Guinness went into a positive decline.

It was unexpected in a way, because Cleo and Guinness didn't really interact all that much; they kind of didn't speak the same language.  Cleo, typical of her breed, was independent, curious, and eccentric; Guinness is strongly bonded to us (especially my wife, whom he follows around like a shadow), protective, and thinks that chasing a tennis ball is the most fun hobby ever.  But when Cleo died, Guinness went into a prolonged period of grief that nearly matched our own.

Recent experiments have shown that the neurochemical underpinning of emotions in our brain are shared by dogs and cats -- they experience a surge of oxytocin when they see their friends (whether human or not) just like we do.  When I go out to get the mail and come back inside under a minute later, and my puppy Jethro greets me as if he thought I'd abandoned him forever and ever and OMIGOD I'M SO GLAD YOU'RE BACK, he really is experiencing something like the rush we feel when seeing someone we dearly love.

Of course, he does like belly rubs, too.

If you needed one more piece of evidence of the falsehood of my long-ago professor's contention that non-human animals don't experience emotion, it came out this week in the journal Applied Animal Behaviour Science.  A study of pet cats -- an animal widely considered to be independent and self-sufficient -- experience genuine grief when a family member dies, even if that family member is another pet...

... and even when it's a dog.

The study analyzed the behavior of 450 cats that had gone through loss, and the results were widely consistent -- grieving cats slept and ate less, vocalized more, hid more, refused to play but became clingy, and appeared to look for their lost friend.  "Unlike dogs, we tend to think that cats are aloof and not social," said Jennifer Vonk, a comparative/cognitive psychologist at Oakland University and a co-author of the work.  "They may not form packs like wild dogs, but in the wild, cats still tend to band together and form hierarchies...  I think we’ve been mischaracterizing them."

The divide between ourselves and our pets -- and by extension, between us and the rest of the natural world -- is far narrower than many of us think.  A lot of pet owners say "he understands every word I say" (I've been guilty of that myself), which is certainly untrue, but the emotional resonance between pets and the rest of the members of their household is undeniable.  And grief is experienced deeply by a great many more species than ourselves.

But y'all'll have to excuse me.  Jethro is looking at me with his big, soulful brown eyes.  He hasn't lost a friend or anything, but probably would like a belly rub.

Gotta keep my priorities straight.

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Since this post is pet-related, I thought it was a good opportunity to put in a plug for our Third Annual Pandemic Pottery Sale.  My wife and I are both amateur potters, so we tend to get overrun with pottery we don't have space for.  Two years ago, we came up with the idea of selling a bunch of it and donating the proceeds to charity.  This year the recipient we chose is the fabulous Stay Wild Animal Rescue and Rehabilitation (where we got our two wonderful rescue dogs Jethro and Rosie).  They do fantastic work and are constantly dealing with costly animal care and bringing dogs and cats from states with kill shelters (Jethro came from Georgia, Rosie from Texas), which is crazy expensive.

The way it works is if you see a piece you like, you make a bid on it.  If no one else bids, it's yours.  If there are competing bids, the high one gets the piece.  A few provisos: first, the shipping costs outside of the United States are prohibitively expensive -- so unfortunately, this event is limited to our American friends.  Second, all of the pieces EXCEPT AS MARKED are food safe, microwave safe, and dishwasher safe.  However: we work with stoneware clay, which is not completely vitrified even when glazed and fired properly, so if you're using a piece to hold water long-term (mostly this caution is for vases) make sure to put something underneath it so you don't ruin nice furniture.  (Many of them won't leak, but don't take the chance.)

Once most of the pieces are claimed, we'll present Jane George, who runs Stay Wild, with what will hopefully be a big check!

So check out the website, take a look at the gallery, and bid on what takes your fancy!  Feel free to pass the link along to interested friends.  Enjoy!

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Catcalling

For many years we owned two cats, Puck and Geronimo.

Imagine two soft, gentle, affectionate, fluffy kitties.  Puck and Geronimo were the exact opposite of what you just pictured.

What neither of our cats looked even remotely like.  [Image courtesy of the Creative Commons Nicolas Suzor from Brisbane, Australia, Cute grey kitten, CC BY-SA 2.0]

Puck and Geronimo were siblings, both long-bodied, tough, lean, and solid black.  Puck had some odd features, though.  She had one single white whisker accentuating a face that was already kinda... off.  Her eyes didn't quite line up, so you never could be 100% sure of where she was looking.  She had one broken fang, so her tongue frequently protruded from the side of her mouth.  Plus, her voice sounded like a creaky wheel.  She was actually quite a sweet, affectionate cat, but even dedicated cat lovers had to admit she looked like she had a screw loose.

Geronimo, on the other hand, hated everyone, with two exceptions: (1) my wife; and (2) our dog, Grendel.  When we adopted Grendel, we were assured by the shelter that he was great with cats.  But shelter staff -- no insult intended, they do amazing work -- can sometimes overplay animals' good qualities in the interest of getting them adopted, so when we brought him home, we introduced him to the cats on leash, with me hanging on to my end of it like grim death.  Puck, he ignored completely.  Then he came up and sniffed Geronimo, who sniffed him back (without hissing, which was Geronimo's primary way of communicating with the entire world).  So I tentatively relaxed my end of the lead...

... and Grendel lifted his big front paw and body-slammed Geronimo to the floor.

I leaped forward, yelling, "Noooooooo....!!!!"  But then Grendel started to lick Geronimo's face.  Geronimo, although still pinned to the ground, started purring.  And thus was born the only interspecies gay romance I've ever witnessed.  They were boyfriends for as long as we had them.

But other than those exceptions, Geronimo viewed the entire world with something between haughty disdain and utter loathing.  Sometimes I'd look up from what I was doing to find Geronimo staring at me, his yellow eyes narrowed to slits, and he was clearly thinking, "I am going to disembowel you in your sleep."

What brings all this up is a paper that appeared in Nature last week about some research done at Kyoto University.  A team led by animal behavioral psychologist Saho Takagi did a clever set of experiments to see if cats could not only learn their own names but the names of other cats, and their results suggest that the answer is yes.

They worked with two sets of cats -- household pets, and "café cats."  Apparently in Japan, it's common to have cats living in cafés, for the benefit of patrons who would like to pet cats while they have their coffee and pastries, or at least have cats glaring at them and making harsh judgments about their general appearance.  They had their test subjects "softly restrained" by volunteers, who I hope were wearing body armor at the time, and the cats were given vocal stimuli (the cats' own names, the names of other cats living in the same place, and neutral words falling into neither categories), along with photographs of different cats, sometimes the photograph of the cat being named, sometimes not.

They found that the cats tended to look more quickly and for a longer duration at photographs when the photograph was of the cat being named.  It was evident that the cats tested did indeed know the names of the cats that cohabited with them.  (Except for one test subject who "completed only the first trial before escaping from the room and climbing out of reach.")

I found these data mildly surprising, considering that our own cats gave no evidence of knowing either their own names or each other's.  Geronimo usually responded to being called as follows:

Us:  Geronimo!!!

Geronimo:  Fuck you.

Us:  Geronimo, come get your dinner!

Geronimo:  Fuck you.

Us:  C'mon, kitty kitty kitty!

Geronimo:  Fuck you.

Us: We have a plate of fresh salmon for you!

Geronimo:  Fuck you...  Salmon?  Well, okay, maybe this time.

So I don't know how we'd have been able to tell if he did know his name.

But all of this does point out something I've always thought, which is that a lot of animals are way smarter than we give them credit for.  I know one of our current dogs, Guinness, always gives us this incredibly intent look when we talk to him, as if he's trying his hardest to understand every word we're saying.  Our other dog, Cleo, spends a lot of time ignoring us, but she's a Shiba Inu, which in my opinion is a cat wearing a dog suit.

So okay, maybe that doesn't exactly support the contention that our pets are really smart.  But my point stands.

In any case, that's our cool piece of animal behavior research for today.  If you are the owner of two or more cats, see if you can figure out if they know each other's names.

If any of your cats have a temperament like Geronimo's, you might want to have fresh salmon handy.

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Escaping the mill

Content warning: this post is about the mistreatment and neglect of animals.  There's nothing graphic or gratuitous, but if you're sensitive to such things and would prefer not to read about them, you may want to sit this one out.

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I'm going to do something today that I almost never do: use this blog to plead with you, directly and personally, to do something.

I'll say it straight out.  If you are considering getting a pure-bred pet, please please please do some research and make sure that the breeder the pet comes from is reputable and treats their animals humanely.

This, unfortunately, rules out the lion's share of the pure-bred puppies and kittens you find at most of the big-chain pet stores.  You can often find "bargains" there -- pedigreed pets that will cost you one-half to one-third what you'd pay to a good breeder -- but that money saved comes at a terrible cost.

I'm not referring to the fact that most "puppy mills" and "kitten mills" don't do much in the way of screening for genetic health.  (An example is the most common congenital problem in large dog breeds, hip dysplasia.)  I'm also not going to get into the wisdom and logic of pure breeding as a practice in and of itself; perhaps that will be a topic for another day.

The reason you should never purchase puppies and kittens from unknown or questionable sources is because of the way disreputable breeders treat the animals they own.  Pure-bred dogs and cats owned by these people are used for one thing: producing income.  They are only valuable as money generators.  Dogs and cats who have been selectively bred for centuries for their ability to connect emotionally and bond to humans are kept isolated in cages, rarely if ever allowed to play with humans or the other animals confined in the same facility, and once their useful life as reproduction machines is over, they are either euthanized or given up to rescues.

The owners of puppy and kitten mills are usually pretty good at dancing on the line between neglect and outright abuse.  The difficulty for regulatory agencies is proving that they've crossed that line; it's time-consuming and often expensive to bring a suit against owners unless the case is clear-cut (which it seldom is).

An example -- and the reason this topic comes up -- is my new dog, Cleo.  I mentioned here that I got her from a rescue a month ago.  She's a pure-bred Shiba Inu, a Japanese breed that looks a little like a cross between a dog and a fox.  She spent her first four years with a breeder who should, in my opinion, never be allowed within a hundred meters of a dog for the rest of his life.  When Cleo was a puppy, she injured her left eye, and the injury was ignored until it looked like it might be life-threatening.  By that time, it was bad enough that she had to have the eye removed.  If that's not bad enough, her owner apparently decided the way to stop the dogs from barking was to bang on their cages with a metal pipe.  The result is that Cleo is terrified of loud noises -- even closing a cabinet door makes her startle.

It's taken her a month to begin to understand that she's not going to be locked up any more.  Her first three weeks with us, she became panicked whenever she saw a door closing.  We'd leave the door into the back yard open for her -- despite the fact that it's winter -- and at first, we thought it was kind of funny that she'd walk inside, then turn around and walk back out, then in, then out, sometimes for twenty minutes before she'd commit.  It became much less amusing when we figured out why she was doing it.  She's beginning to learn that she can go outside (or back inside) whenever she wants to, and doesn't need to freak out that once the door closes, she'll be stuck for hours or days.

She's also having to figure out how to play.  One really positive thing is that she and our other dog, a big galumphing galoot of a pittie mix named Guinness, hit it off right away.

Best buds.  Yes, the dogs have their own couch.  No, we don't spoil them at all, I don't know what you're talking about.

It was simultaneously heartwarming and heart-wrenching to watch her and Guinness romping in the snow two days ago.  We got our first big snowfall of the winter on Monday, and it quickly became obvious that she'd never had the opportunity to play in the snow before.  I spent a half-hour standing at my kitchen window watching them galloping around -- the contrast between Guinness's ponderous trot and Cleo's spring-loaded, gazelle-like bounce was hilarious.

Cleo's first time playing in the snow -- Monday, January 17, 2021

The emotional scars from her past aren't going to go away quickly, and I'm well aware that we are going to have to be patient, gentle, and reassuring to her, until she becomes convinced that she's in a safe place with people who love her.  The thing I've said to her the most often, when something panics her and she freezes, shivering uncontrollably, is, "You don't have to be afraid, little one.  You're safe.  No one will ever hurt you again."  I know she can't understand the words, but I think she's beginning to understand the intent.  She spends a lot of time sitting next to me, dozing, pressed against my leg -- making up for all those lonely, desolate years when she was never touched with love and compassion.  We're lucky that her mistreatment didn't make her scared of all humans.  Instead it's left her craving someone to trust and to bond with, and she's fortunate we're here to be that.

And so are we.  She's a sweet, gentle, funny little girl, who is beginning to learn how to be playful -- yesterday evening she bounced around in the living room, barking at her rawhide chew, tossing it up in the air, play-bowing and tail wagging furiously, and she kept checking in with us as if she couldn't quite believe we were letting her have fun with it.

So I'll reiterate my plea to be careful where you buy your dogs and cats from.  No animal, ever, should be treated the way Cleo was.  I know that it's not the fault of the puppies and kittens for sale in stores that they came from mills, and they need homes too, but the flow of money to disreputable breeders has got to be stopped.  Put pressure on pet stores to certify that their animals came from breeders who treat them kindly.  Put pressure on state legislators to pass laws cracking down on breeders who neglect the animals they own.  Donate to the Humane Society or the SPCA.  If you don't want to do a cash donation, then volunteer at your local shelter, or call them and find out what supplies they are in need of.

Consider adopting a pet from a rescue.  Yes, it means you'll probably have to work with your new friend to overcome what happened in the past.  But I'm writing this right now with Cleo snoozing peacefully in my lap, safe and warm and secure, and she is returning to me in love and devotion everything I've given her and more.

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Since reading the classic book by Desmond Morris, The Naked Ape, when I was a freshman in college, I've been fascinated by the idea of looking at human behavior as if we were just another animal -- anthropology, as it were, through the eyes of an alien species.  When you do that, a lot of our sense of specialness and separateness simply evaporates.

The latest in this effort to analyze our behavior from an outside perspective is Pascal Boyer's Human Cultures Through the Scientific Lens: Essays in Evolutionary Cognitive Anthropology.  Why do we engage in rituals?  Why is religion nearly universal to all human cultures -- as is sports?  Where did the concept of a taboo come from, and why is it so often attached to something that -- if you think about it -- is just plain weird?

Boyer's essays challenge us to consider ourselves dispassionately, and really think about what we do.  It's a provocative, fascinating, controversial, and challenging book, and if you're curious about the phenomenon of culture, you should put it on your reading list.

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

Catty behavior

Ever heard of the cui bono principle?

Cui bono? is Latin for "who benefits?"  It's been used for centuries as a central question in criminal cases; to figure out who's guilty of a crime, the first thing to determine is who benefitted from it.  But it is also critical to questions of evolutionary biology.  There are behaviors in the biological world that seem unnecessarily risky, or even suicidal, and it's hard to imagine how they'd be selected for.

So... who benefits?

Take, for example, the strange behavior of certain ants.  Ground-dwelling ants, when threatened, usually have one of two responses; rush out and try to sting or bite whatever's threatening them, or move downward (and underground) to hide.  But some ants were observed to have a third, and bizarre, response: faced with a threat, they climb upwards on plant stems, and then just docilely sit there -- and, frequently, get eaten (along with the plant) by herbivorous animals.

The reason for this weird behavior is positively grotesque.  It turns out that the seemingly-suicidal ants were infected with a brain parasite called a lancet worm (Dicrocoelium dendriticum) that, in order to complete its life cycle, has to pass through the digestive tract and liver of a ruminant (sheep, cow, or goat).  So the worm reprograms the ant's brain to make it do something that will ultimately end up with its being turned into lunch.  

Too bad for the ant.  But cui bono?  The worm, of course.  It hijacked the ant's brain to make it an unwilling participant in the worm's life cycle.

This is hardly the only example of the cui bono principle, and far from the creepiest one.  Ready to get completely skeeved out?

You may know of the pathogen Toxoplasma gondii in its connection to the recommendation by doctors that pregnant women not clean cat litter boxes.  The pathogen, which is neither a bacteria nor a virus but a protist, is carried by cats and excreted with the urine; and a pregnant woman who contracts toxoplasmosis risks birth defects in her unborn child.

Toxoplasma, however, is found in other animals besides cats, and in fact it was some recent research into hyenas that brought it to mind today.  A study out of the University of Colorado that appeared in Nature Communications a few months ago showed that wild populations of hyenas have a high rate of infection, and the weirdest result is seen in infected hyena cubs.  They, like the unfortunate ants, have a behavioral consequence of infection; they become bold, and seem to lose their perception of lions and other predators as dangerous.  They're far more likely to be killed than healthy, uninfected hyena cubs -- which, of course, benefits the pathogen because it then passes on to the lion.  The pathogen, in essence, is programming its host to engage in behavior that will make it more likely to jump to another host.

[Image licensed under the Creative Commons New Jersey Birds, Spotted hyena cubs in Limpopo, CC BY-SA 2.0]

So, a weird and gruesome outcome of being infected with a tropical disease, right?  Nothing for us humans to worry about, right?  Well, what you may not know is that there is a significant likelihood that you have toxoplasmosis right now.  In fact, if you have ever owned a cat, the probability stands close to 100%.

A study done a while back by Kevin Lafferty, of the University of California, suggests that as many as three billion people may have a dormant Toxoplasma infection.  Yes, dear readers, you read that right; that's three billion with a "b," as in a little less than half of the human population.  Turns out that Lafferty's research indicated that when you get toxoplasmosis, you get flu-like symptoms for a couple of days, and then the symptoms abate -- but for most of us, the protist goes dormant, and we carry around the parasite for life.

This is creepy enough, but wait'll you hear what it does to you.

Lafferty's research showed that in mammalian hosts, the Toxoplasma organism invades, and becomes dormant in, the host's brain cells.  Not only hyenas become bolder around predators; mice and rats do, as well, aiding in the passage of the germ between rodents and domestic cats.  Lafferty's study, though, goes a step further, and looks at what latent Toxoplasma infection does to humans -- and he found  it seems to cause significant personality changes.

Now, it doesn't make us have a high affinity for cats, which would make sense, and would explain Crazy Cat Lady Syndrome, in which some people think it's normal to own thirty cats, and somehow seem immune to the truly cataclysmic odor that their houses attain.  No, what actually happens is more subtle.  Apparently, if you have Toxoplasma, you're more likely to be neurotic.  People who tested positive for antibodies for Toxoplasma scored far higher on personality assessments in the areas of guilt-proneness, anxiety, and risk of depression.  These effects were so pronounced that Lafferty speculates that it could account for certain differences between cultures.

"In some cultures, infection is very rare," Lafferty said, "while in others, virtually everyone is infected.  The distribution of Toxoplasma gondii could explain differences in cultural aspects that relate to ego, money, material possessions, work, and rules."

I find this speculation fascinating.  The idea that my neuroses might not be due to my genes or upbringing, but because I'm carrying around a parasite in my brain, doesn't create the level of Icky-Poo Factor that you might expect.  Of course, I'm a biologist, and so I'm at least on some level accustomed to thinking about creepy-crawlies.  But the idea that some sort of a microorganism could affect my behavior strikes me as weirdly interesting, particularly since I've had at least one cat in my household for a significant chunk of the past forty years.

So, maybe our personalities aren't as static as we'd like to think -- they can be influenced by a great many circumstances outside of our control.  Add parasite infestations to that list.  And if that whole idea upsets you too much, take comfort in the fact that Lafferty's research has spurred medical researchers to try to find a drug that can destroy the germ.  Nothing's been certified for human use so far, so don't cancel your appointment with your therapist just yet, but there are a couple that are looking promising.  What's uncertain is whether, if the pathogen were eradicated, it would reverse the changes in the brain -- if, for example, nervous, neurotic people would find themselves less anxiety-prone -- or if the alterations in the brain are more or less permanent.  But I, for one, would volunteer to give it a try, once (or if) the medication becomes available.

Until then, you should probably shouldn't worry.  What's a few brain parasites among friends, after all?  In fact, just forget I brought it up.  Relax, go and sit in your recliner, and pet your cat, Mr. Fluffkins, for a while.

You'll feel better.  Trust me.

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I've mentioned before how fascinated I am with the parts of history that still are largely mysterious -- the top of the list being the European Dark Ages, between the fall of Rome and the re-consolidation of central government under people like Charlemagne and Alfred the Great.  Not all that much was being written down in the interim, and much of the history we have comes from much later (such as History of the Kings of Britain, by Geoffrey of Monmouth, chronicling the events of the fourth through the eighth centuries C.E. -- but written in the twelfth century).

"Dark Ages," though, may be an unfair appellation, according to the new book Matthew Gabriele and David Perry called The Bright Ages: A New History of Medieval Europe.  Gabriele and Perry look at what is known of those years, and their contention is that it wasn't the savage, ignorant hotbed of backwards superstition many of us picture, but a rich and complex world, including the majesty of Byzantium, the beauty and scientific advancements of Moorish Spain, and the artistic genius of the master illuminators found in just about every Christian abbey in Europe.

It's an interesting perspective.  It certainly doesn't settle all the questions; we're still relying on a paucity of actual records, and the ones we have (Geoffrey's work being a case in point) sometimes being as full of legends, myths, and folk tales as they are of actual history.  But The Bright Ages goes a long way toward dispelling the sense that medieval Europe was seven hundred years of nothing but human misery.  It's a fascinating look at humanity's distant, and shadowed, past.

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

Cats in boxes

Any cat owners amongst my readers will undoubtedly know about the strange propensity of cats to climb into boxes.  Apparently it works for cats of all sizes:

With apologies to Robert Burns, a cat's a cat for a' that.

In fact, it doesn't even have to be a real box:

I've never heard a particularly convincing explanation of why cats do this.  Some people suggest it's because being in close quarters gives them a sense of security, perhaps a remnant of when they lived in the wild and slept in burrows or caves.  Me, I suspect it's just because cats are a little weird.  I've been of this opinion ever since owning a very strange cat named Puck, who used to sleep on the arm of the couch with one front and one back leg hanging limp on one side of the arm and the other two dangling over the other side, a pose that earned her the nickname "Monorail Cat."  She also had eyes that didn't quite line up, and a broken fang that caused her tongue to stick out of one side of her mouth.  She was quite a sweet-natured cat, really, but even people who love cats thought Puck looked like she had a screw loose.

The topic comes up because of a delightful piece of research that came out a few days ago in the journal Applied Animal Behaviour Science.  The paper was titled "If I Fits, I Sits: A Citizen Science Investigation into Illusory Contour Susceptibility in Domestic Cats," by Gabriella Smith and Sarah-Elizabeth Byosiere (of Hunter College) and Philippe Chouinard (of LaTrobe University), and looked at data collected from cat owners to find out if cats are fooled by the Kanizsa Rectangle Illusion.

The Kanizsa Rectangle Illusion is an image that tricks the brains into seeing contours that aren't there.  Here's one representation of it:

To most people, this looks like an opaque white rectangle laid over four black hexagons, and not what it really is -- four black hexagons with triangular wedges cut out.  Apparently the brain goes with an Ockham's Razor-ish approach to interpreting what it sees, deducing that a white rectangle on top of black hexagons is much more likely than having the cut-out bits just happening to line up perfectly.  It's amazing, though, how quickly this decision is made; we don't go through a back-and-forth "is it this, or is it that?"; the illusion is instantaneous, and so convincing that many of us can almost see the entire boundary of the rectangle even though there's nothing there.

Well, apparently, so can cats.  And, as one would expect, they sit in the middle of the nonexistent rectangle just as if it was a real box.  The authors write:

A well-known phenomenon to cat owners is the tendency of their cats to sit in enclosed spaces such as boxes, laundry baskets, and even shape outlines taped on the floor.  This investigative study asks whether domestic cats (Felis silvestris catus) are also susceptible to sitting in enclosures that are illusory in nature, utilizing cats’ attraction to box-like spaces to assess their perception of the Kanizsa square visual illusion...  [T]his study randomly assigned citizen science participants booklets of six randomized, counterbalanced daily stimuli to print out, prepare, and place on the floor in pairs.  Owners observed and videorecorded their cats’ behavior with the stimuli and reported findings from home over the course of the six daily trials...  This study revealed that cats selected the Kanizsa illusion just as often as the square and more often than the control, indicating that domestic cats may treat the subjective Kanizsa contours as they do real contours.

 It's a fascinating result, and indicative that other animal species see the world much as we do.  It still doesn't explain why cats like to sit in boxes, though.  I think my conclusion ("cats are weird") covers it about as well as anything.  But at least in one way, our perceptual/interpretive centers are just as weird as the cats' are.  I'm not inclined to go sit in a box, but it does make me wonder what our pets would think if we showed them other optical illusions.

I doubt my dogs would be interested.  If what they're looking at has nothing to do with food, petting, or playing, they pretty much ignore it.  Must be nice to see the world in such simple terms.

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Ever get frustrated by scientists making statements like "It's not possible to emulate a human mind inside a computer" or "faster-than-light travel is fundamentally impossible" or "time travel into the past will never be achieved?"

Take a look at physicist Chiara Marletto's The Science of Can and Can't: A Physicist's Journey Through the Land of Counterfactuals.  In this ambitious, far-reaching new book, Marletto looks at the phrase "this isn't possible" as a challenge -- and perhaps, a way of opening up new realms of scientific endeavor.

Each chapter looks at a different open problem in physics, and considers what we currently know about it -- and, more importantly, what we don't know.  With each one, she looks into the future, speculating about how each might be resolved, and what those resolutions would imply for human knowledge.

It's a challenging, fascinating, often mind-boggling book, well worth a read for anyone interested in the edges of scientific knowledge.  Find out why eminent physicist Lee Smolin calls it "Hugely ambitious... essential reading for anyone concerned with the future of physics."

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

 

Cats and quakes

I ran across two stories yesterday that fall squarely into the "You People Do Realize You Have Bigger Problems To Worry About, Right?" department.

In the first, we have a senior Saudi cleric who has issued a fatwa on people taking selfies with cats.  Well, not just with cats.  Also with wolves.  But since cat selfies are way more common than wolf selfies (more's the pity), I can see why he specifically mentioned the cats.

The subject came up because of a question asked at a talk that Sheikh Saleh Bin Fawzan Al-Fawzan was giving, in which someone asked about a "new trend of taking pictures with cats which has been spreading among people who want to be like westerners."  Al-Fazwan was aghast.

"What?" he asked.  "What do you mean, pictures with cats?"

Because that's evidently an ambiguous phrase, or something.  Maybe it has subtleties in Arabic I don't know about.

So the questioner clarified, and after he got over his outrage, Al-Fazwan gave his declaration.  "Taking pictures is prohibited," he said.  "The cats don't matter here."

Which is kind of odd, given that he was being filmed at the time.  But rationality has never been these people's strong suit.

"Taking pictures is prohibited if not for a necessity," Al-Fazwan went on to say.  "Not with cats, not with dogs, not with wolves, not with anything."

Wipe that smirk off your face, young lady.  Allah does not approve of you and Mr. Whiskers.

So alrighty, then.  Now that we've got that settled, let's turn to another thing a prominent Muslim cleric is worrying about, which is: gay sex.

Of course, gay sex seems to be on these people's minds a lot, and also on the minds of their siblings-under-the-skin the Christian evangelicals.  But this time, the cleric in question, Mallam Abass Mahmud of Ghana, has said that the practice is not only prohibited because it's naughty in Allah's sight (although it certainly is that as well), but because it causes...

... earthquakes.

"Allah gets annoyed when males engage in sexual encounter," Mahmud said in an interview, then went on to add, "Such disgusting encounter causes earthquakes."

As an example, he says that this is why Sodom and Gomorrah were destroyed.  Although as I recall from my reading of Genesis chapter 19, it wasn't an earthquake in that case, but having "fire and brimstone rained down upon them... so that the smoke of the country went up as the smoke of a furnace."  But I guess since gays are apparently the most powerful force of nature known, there's no reason why they couldn't also cause a volcanic eruption or something.

On the other hand, if two guys having sex is causing the ground to shake, they must really be enjoying themselves.  I don't know whether to feel scared or jealous.

What crosses my mind with all of this is that there are a few more urgent concerns in the Muslim world than worrying about cat selfies and guys making love.  Human rights, tribalism, poverty, wealth inequity, corruption, terrorism, radical insurgencies, drought.  To name a few.  You have to wonder if focusing their followers on nonsense is simply a way of keeping the hoi polloi from realizing what a horror much of the Middle East has become under the leadership of people like this.

And given the reactions they got -- which, as far as I can tell, were mostly nodding in agreement -- it appears to be working.  So if you go to Saudi Arabia or Ghana, just remember: no kitty selfies or gay sex.  Or, Allah forfend, you and your gay lover having sex then celebrating by taking a photograph of the two of you with your cat.  That'd probably just cause the Earth to explode or fall into the Sun or something.

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This week's Skeptophilia book recommendation is pure fun: Arik Kershenbaum's The Zoologist's Guide to the Galaxy: What Animals on Earth Reveal About Aliens and Ourselves.  Kershenbaum tackles a question that has fascinated me for quite some time; is evolution constrained?  By which I mean, are the patterns you see in most animals on Earth -- aerobic cellular respiration, bilateral symmetry, a central information processing system/brain, sensory organs sensitive to light, sound, and chemicals, and sexual reproduction -- such strong evolutionary drivers that they are likely to be found in alien organisms?

Kershenbaum, who is a zoologist at the University of Cambridge, looks at how our environment (and the changes thereof over geological history) shaped our physiology, and which of those features would likely appear in species on different alien worlds.  In this fantastically entertaining book, he considers what we know about animals on Earth -- including some extremely odd ones -- and uses that to speculate about what we might find when we finally do make contact (or, at the very least, detect signs of life on an exoplanet using our earthbound telescopes).

It's a wonderfully fun read, and if you're fascinated with the idea that we might not be alone in the universe but still think of aliens as the Star Trek-style humans with body paint, rubber noses, and funny accents, this book is for you.  You'll never look at the night sky the same way again.

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

Why the sad face?

Springboarding off Saturday's post about non-human animals having emotions, today we're going to look at a study that came out a couple of weeks ago in Frontiers of Veterinary Science that demonstrates that not only do animals have emotions, they've evolved to be able to play on ours.

In a paper with the rather intimidating title "The Application of Geometric Morphometrics to Explore Potential Impacts of Anthropocentric Selection on Animals' Ability to Communicate via the Face: The Domestic Cat as a Case Study," animal behaviorists Lauren Finka and Mark Farnsworth (of Nottingham Trent University), Stelio Luna (of São Paulo State University), and Daniel Mills (of the University of Lincoln) looked at an interesting phenomenon; the way human selection of animals for pets has led to the animals evolving traits that trigger a nurturing response in the owners.  A particularly interesting one is the "inner eyebrow raising muscle," which in domestic dog breeds is far more highly developed than in wild dogs, and which causes the furrowed brow "sad puppy" look any dog owners out there will no doubt recognize immediately.  My lovable rescue dog Grendel was the past master of this particular expression:

No, he was not spoiled.  Don't even suggest such a thing.

People seeing Grendel usually took one look at him and said, "Oh, you poor poor puppy!  Why the sad face?  Here, puppy, have a cookie."  Which, of course, led him to understand that looking sad got him what he wanted.

Evolution for the win.

The study that came out a couple of weeks ago, however, took a look at cats, which in general have less emotionally expressive faces than dogs do.  My wife's cat, Geronimo, who died a couple of years ago at age eighteen, had a spectrum of facial expressions that ran the gamut from "I'm pissed off" to "I hate you," occasionally reaching the level of "fuck off and die."  I know this is ascribing human thoughts to a non-human animal, but whenever Geronimo looked at me, his yellow eyes narrowed to slits, I always came away with the expression that he was plotting to disembowel me in my sleep.

But the current study shows that most domestic cats have a wider range of emotional communication than Geronimo did.  Interestingly, what the researchers called "pain features" -- movements of the face indicative of distress -- were often present in "baby-faced" breeds like Persians even when the animals were not actually in distress, while long-faced breeds like Siamese showed fewer "pain features" even when the animal was in pain.  I wonder if this is why Siamese cats have a reputation for being "aloof" and "independent," and Persians a reputation for being in need of pampering?

The authors write:

The ability of companion animals to readily solicit care from humans is obviously advantageous.  However, it is possible that permanently vulnerable looking individuals might have a diminished capacity to clearly indicate when care is or is not required, as well as to display other information relevant to their actual state or intentions.  Thus, if certain cat breeds are being selected to display “pain-like” features on their faces, these features may serve to solicit unwanted or inadequate attention from their caregivers.  More generally, such types of anthropocentric selection might lead to increased anthropomorphic tendencies.  If, for example, the animal has the appearance of an expression which humans find relatable on some level, even if it is not necessarily reflective of that animals' affective state, it may be used to attribute emotions or characteristics to them.  For example, “grumpy cat” a cat made famous by her coverage on social media, achieved her moniker due to her perceived “frowning” facial appearance.  However, this was likely a result of a combination of her feline dwarfism and paedomorphic [infant-like] features, rather than an expression of her irritability.

One interesting point the authors make is that one possible reason that cats in general have fewer facial cues to solicit nurturing from humans is that they've been in domestication as companions for a far shorter time than dogs have.  The human/dog relationship goes back millennia; and while cats have been used as mousers for centuries, their use as companion animals is of fairly recent origin.  In fact, a large percentage of current domestic cat breeds are under a hundred years old -- in other words, if you trace most "pure-bred" cats' ancestry back two hundred years, they all descend from a population of generic-looking felines that began to be heavily selected when people started keeping them in their homes, and expecting something more out of them than just ridding the house of rodents.

In any case, as the authors point out, the advantage to the pet is obvious.  In our case, our dogs play us like fiddles.  One of our current dogs, a lovable big galoot named Guinness, knows that to get what he wants all he has to do is put his head in my lap and just stand there.  I've tried ignoring him, but he knows that patience always gets him what he wants (usually petting) in the end.  If I make eye contact with him, the tail starts wagging, because he knows he won.

As usual.

But as my wife points out, the fact that they've evolved to yank on our heartstrings isn't entirely a one-way relationship.  We get companionship and love and lap-warming, and there's real value in that.  So really, I'm perfectly okay with being used.  A petless home would be a lot cleaner and quieter, but it would also be a lot colder, lonelier, and sadder.

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As a biologist, I've usually thought of myself as immune to being grossed out.  But I have to admit I was a little shocked to find out that the human microbiome -- the collection of bacteria and fungi that live in and on us -- outnumber actual human cells by a factor of ten.

You read that right: if you counted up all the cells in and on the surface of your body, for every one human cell with human DNA, there'd be ten cells of microorganisms, coming from over a thousand different species.

And that's in healthy humans.  This idea that "bacteria = bad" is profoundly wrong; not only do a lot of bacteria perform useful functions, producing products like yogurt, cheese, and the familiar flavor and aroma of chocolate, they directly contribute to good health.  Anyone who has been on an antibiotic long-term knows that wiping out the beneficial bacteria in your gut can lead to some pretty unpleasant side effects; most current treatments for bacterial infections kill the good guys along with the bad, leading to an imbalance in your microbiome that can persist for months afterward.

In The Human Superorganism: How the Microbiome is Revolutionizing the Pursuit of a Healthy Life, microbiologist Rodney Dietert shows how a lot of debilitating diseases, from asthma to allergies to irritable bowel syndrome to the inflammation that is at the root of heart disease, might be attributable to disturbances in the body's microbiome.  His contention is that restoring the normal microbiome should be the first line of treatment for these diseases, not the medications that often throw the microbiome further out of whack.

His book is fascinating and controversial, but his reasoning (and the experimental research he draws upon) is stellar.  If you're interested in health-related topics, you should read The Human Superorganism.  You'll never look at your own body the same way again.

[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.

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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!]