Readers’ wildlife photos

February 20, 2021 • 8:00 am

We last heard from reader Lance Emrick five years ago, but he promises to be more regular with his photos. I hope so, as these ones are good, and include WILD FELIDS! (And please send in your own photos.)

Lance’s captions are indented; click on the photos to enlarge them.

Here are some snapshots of the neighbors for Reader Wildlife. We’re at 8600 feet north of Rocky Mountain National Park in Colorado; these are all from within 200’ of the front door, some through the living room windows.

Moose (Alces alces) were reintroduced to the North Platte headwaters area about 40 years ago, and have been very successful. We see them frequently through the Summer and Fall. This fellow is in July velvet:

Mule Deer (Odocoileus hemionus) are common and surprisingly casual around us and our noise:

There are a couple of large Elk herds (Cervus canadensis) in the area, but we rarely see them in daylight. The recent wildfires funneled them through our neighborhood more than usual this Fall – night time bugling from the nearby meadow!:

This American Badger (Taxidea taxus) had been digging around in well tailings, giving him this odd coloring:

We’ve been here long enough to watch several predator/prey cycles play out, particularly with the Bobcats (Felis rufus). They take over the area when they’re around – looking in windows, hanging out on the deck:

And here waiting for a vole under the bird feeder:

Opposite the cats are the Golden-Mantled Ground Squirrel (Spermophilus lateralis):

. . .and Mountain Cottontail (Sylvilagus nuttallii) – both with strong comebacks the past couple of years while the cats have been elsewhere:

The indoor Shelter fauna have appreciated the current swing of the cycle:

Long-Tailed Weasels (Mustela frenata) will take over prime housing spots from the rabbits and ground squirrels. Around here they still turn pure white with a black tail tip during Winter:

The Wild Turkeys (Meleagris gallopavo) are fascinating to watch, but get really messy and aggressive as the guys get to their most colorful and romantic. I had to try the Parks and Wildlife recommendation of “run around, wave your arms like a big turkey” as a deterrent last Spring:

Pine Squirrels (Red Squirrel or Chickaree) (Tamiasciurus hudsonicus) are a busy year-round presence, in this case apparently unconcerned about hawks. [JAC: I’d title this: “This squirrel approves of this post.”]

Why do catnip and silver vine drive moggies crazy? A group of researchers says the plants could protect them against mosquitos

January 22, 2021 • 10:00 am

There’s a new paper in Science Advances by a group of Japanese researchers who investigated the attraction of cats to catnip and silver vine. This involved isolating the compounds that attracts cats, showing that they activate the pleasure centers of cats (duh!), and, most important, proposing and testing an adaptive hypothesis for why cats rub all over catnip (Nepeta cataria, in the mint family) as well as on a related cat-drug plant, silver vine (Actinidia polygama, in a different family).

Their theory, which is theirs, is that the these compounds, which plants have evolved to repel insects (aphids), do a similar job for the cats, but act for them as a mosquito repellant. The paper is below, and free, but let me add that I don’t think their answer, while it might be correct, is strongly convincing—for reasons I’ll discuss.

Click on the screenshot to access the article. You can also get the pdf here, find the full reference is at the bottom, and see a News & Views about the paper in Science, “Why cats are crazy for catnip,” written by Sofial Moutinho, which doesn’t mention any problems with the paper and also omits a fascinating line of speculation.

First, some biogeography and history for cat owners. Catnip, while native to Europe, the Middle East, and Central Asia, has been planted widely throughout the world, and is the drug of choice for American and European cats. In contrast, silver vine is native to both Japan and China, and in Asia has supplanted catnip as the weed to give your moggy. Some cats who respond to one species won’t respond to the other, and for each species some cats do not show the typical euphoric rubbing and “getting stoned” reaction. In catnip, this is due to genetic variation among cats. More on that later.

With both plants the cat’s  attraction is transitory. If you’ve given nip to your cats, you’ll know that they roll around and get stoned for a few minutes, but then recover and subsequently ignore the weed. This goes along with the authors’ hypothesis below (once you’ve put repellent on your fur, your job is done). Further, the “big cats” like lions, lynx, leopards, and bobcats also show a catnip response, and that has to be incorporated into any hypothesis about adaptation.

Here’s catnip (like mints, it has square stems):

Silver vine:

There’s a bit of history in the paper that drove me to further investigation. The authors say this:

The first reports of the feline behavioral response to silver vine and catnip were described by a Japanese botanist in 1704 and by a British botanist in 1759, respectively. The behavioral response to silver vine has been captured in Japanese culture: An Ukiyo-e (a type of traditional painting) drawn in 1859 depicts a folk story concerning a battle between cats and mice, wherein mice use silver vine as a weapon to intoxicate cats

Well I simply had to find that 1859 painting, but it wasn’t easy. Finally I found it in a tweet by Tom Price. Behold: “Cats Tempted by a Delicious Smell” by Tsukioka Yoshitoshi. Look at those nefarious samurai mice! 

Here’s a short Science video showing both housecats and big cats attracted to filter paper imbued with the isolated attractant, while d*gs ignore it (part of the experiment).

The experiment consisted of several distinct parts.

Isolation and testing of the attractant compounds. The authors chemically fractionated extracts of catnip and silver vine, isolating various compounds and testing them as cat attractants by putting the compounds on filter paper and comparing whether cats were drawn to the experimental papers versus control papers soaked in hexane. They found that the active ingredient in silver vine, which induced head and face rubbing in domestic and feral housecats, was nepetalactol. The attractant in catnip was a related compound, nepetalactone. These are part of the plants’ defensive systems against insects, especially aphids, so they evolved to protect plants from being chewed and sucked.  Here are the two compounds so you can see their chemical similarity (they’re both part of a family called iridoids):

Here’s a sample photo and graph of the tests (the paper has lots of cool photos).  Fraction 3 has the nepetalactol, of course:

(From paper): (B) An image of behavioral assay using cats to find bioactive fractions in purification steps (see movie S1). (C) Duration of face rubbing and rolling over toward fractions 3 and 4 in four cats.

The authors then synthesized these compounds so they’d have them in pure form for further tests. The tests:

Attraction of the plants to various cat species. As we know, house cats are polymorphic for the catnip and silver vine reactions, and that’s what the authors found with silver vine: only about two-thirds of both lab cats and feral cats were “postitive responders”. Because there was more nepetalactol than nepetalactone in plants, and because the silver vine compound was more potent than the catnip compound, most further tests used nepetalactol and its source plant, silver vine.

When filter paper soaked in this compound was given to captive leopards, jaguars, and lynx, all of them showed the face-rubbing and rolling seen in house cats. Dogs showed no reaction because they are no fun.

Activation of the “pleasure” system by nepetalactol. As the authors note, the μ-opioid system, which includes release of endorphins, “controls rewarding and euphoric effects in humans.”  Sure enough, in house cats the beta-endorphins were significantly elevated in cats after sniffing nepetalactone—but not control papers. And a chemical that blocks the μ-opioid system, naloxone, significantly reduced the rubbing and rolling response. The authors conclude that the μ-opioid system is involved in the response to silver vines. In other words, the cats probably experience pleasure when they sniff the stuff. (Taste, by the way, doesn’t seem to play a role here; it’s all done through the nose.)

Mosquito repelling activity of nepetalactol. The compound was shown to be highly repellent to a local mosquito, Aedes albopictus, consistent with previous reports. The authors have in fact patented a mosquito repellent, something reported in Moutinho’s News & Views summary. It’s interesting to contemplate using a mosquito repellent that also attracts cats—a double benefit!

The authors then hypothesized that when cats rub silver vine on their heads and bodies, it acts to repel mosquitoes. They first tested whether cats actually got nepetalactol on their fur when rubbing impregnated filter papers. Unfortunately, they could not detect the compound on cats who had rubbed. So they did a bio-assay: they rubbed filter paper on the faces of cats who had rubbed against impregnated filter paper, and then tested the papers on other cats. Sure enough, the face-wiped papers showed a significantly higher attraction for the secondary cats than did the controls. The statistical significance was not high, though, with probabilities equal to 0.034 and 0.025—pretty close to the “standard cut off” level of significance, 0.05.

Finally, the crucial experiment: do cats who have had their heads treated with pure nepetalactol actually repel mosquitoes? The researchers rubbed the compound onto cat’s heads, and had a control where the heads were rubbed with solvents. They then anesthetized the cats and stuck their heads into cages containing A. albopictus mosquitoes, seeing how many skeeters landed on the cats’ heads.  They also did the experiment with cats who had rubbed their heads on silver vine leaves.

In both cases the cats who had the compound on their heads showed significantly fewer mosquitoes landing on them than on the control cats (again, the results, while statistically significant, aren’t overwhelmingly so, with p values of 0.033 and 0.019 respectively). The authors conclude that “the characteristic rubbing and rolling response functions to transfer plant chemicals that provide mosquito repellency to cats.”

The upshot—and some issues:

The authors have a strong adaptationist bent in the paper, looking for the adaptive significance of the catnip reaction. And yes, they’ve shown a possible one, but there are lots of gaps in their story.

1.) Does resistance to this once geographically limited species of mosquito (now more widespread after human conveyance) confer higher fitness on the cats?  There’s no evidence for this. The authors hypothesize that other mosquitoes that might be repelled carry diseases like yellow fever, dengue, and Zike viruses, but are these serious diseases of wild cats, including leopards and lynx? And are these other species of mosquitoes repelled by these iridoids? (Don’t forget, they didn’t test catnip, just silver vine, though I suspect they’d get similar results with nepetalactone from catnip.) Remember too that northern cats like lynx also show the response, but do not contract tropical diseases like dengue and yellow fever.

An alternative hypothesis floated by the authors is that cats, when stalking prey, have to remain motionless for long periods, and that might be hard if mosquitoes are biting you. If you’ve rolled on silver vine and catnip, you might be less plagued by mosquitoes, less likely to move, and thus less likely to be detected by prey. As the authors note, “Face rubbing against plant sources of the repellent will help to protect the face and head of the animal, as the mouth, eyelids, ears, and nose of felines have relatively little fur and are therefore easy targets for mosquitoes.” But they haven’t shown that the stalking behavior of treated and untreated cats differs. This would be fairly easy to do—or at least possible—with house cats and tethered rodents (you don’t want to kill the prey, of course).

So while the authors assert “we have uncovered an adaptive benefit of the behavioral response in cats”, they have uncovered a possible adaptive benefit, but haven’t shown any decisive reproductive advantage of cats who roll on silver vine or catnip.

2.) Do the wild cats who show catnip responses, like the ancestor of the housecat, and the jaguar, leopard, and lynx, coexist or coexisted in the past with silver vine or catnip? The fact that the big cats tested show rolling and rubbing implies that they either independently evolved that response or inherited it from a common ancestor. But for the response to be maintained over the millions of years since cat species diverged from that ancestor, a selective advantage should have been there pretty consistently. The authors don’t consider the problem of the geographic coexistence of these cat species, their ancestor, and of the two plants that evoke a response. That at least should have been mentioned.

3.) What about the polymorphism in house cats? Some house cats show the “nip response” to silver vine and catnip, while others don’t. This variation is known to be genetic, at least for catnip. How variable is it in other cats like lynx? And why have house cats lost a lot of their response?

One possible answer is that house cats no longer either coexist with wild catnip or are so domesticated that the proposed advantages of catnip no longer impose a selection pressure on cats. In other words, the variable response of house cats to catnip could be a “vestigial behavior.” We know that traits that were once useful but are no longer so tend to become more variable and even disappear. This variability is seen, for instance, in human wisdom teeth, considered a superfluous feature and also variable among people (some have them, others don’t, and their eruption is variable, which is why they are often pulled.)

And a fascinating topic the authors neglect: What about the adaptive significance of the pleasure response? 

Both the authors and Moutinho in her N&V piece have a strange take on the fact that cats apparently get pleasure from catnip. The authors hypothesize this:

As many felids rely on stealth to stalk and ambush their prey, requiring them to remain cryptic and often unmoving, a repellent that reduces their susceptibility to both the irritation of biting mosquitoes and the diseases that these insect vectors carry is likely to provide a strong selective advantage. Stimulation of the μ-opioid system might further help by providing analgesia to reduce irritation where biting arthropods have not been repelled.

And Moutinho says this:

Most scientists and pet owners assumed the only reason that cats roll around in catnip was for the euphoric experience, Miyazaki says“Our findings suggest instead that rolling is rather a functional behavior.”

But a “functional behavior” can also go hand in hand with the evolution of “a euphoric experience.” They are not alternative explanations, but complementary ones.

I wish the authors, and Moutinho, had gone down a fascinating byway here: the supposition that cats can evolve to feel pleasure from rubbing on catnip, for feeling pleasure constitutes a powerful impetus for them to rub.” That is, the writers don’t seem to have pondered that the pleasure need not be inherent in the behavior at the very beginning of its evolution, but could have itself evolved to facilitate the behavior.

This resembles the pleasure of the orgasm: it almost certainly evolved as a way to get us to want to copulate, so there’s powerful selective pressure on our pleasure systems to feel fantastic when we copulate. Anything that makes us want to pass on our genes will be selected for, including the great pleasure of orgasms.

Evolution can act not just on behaviors, but on the sensations attendant to them. We like sweets because sugar was good for us in our ancestral habitats, and so our taste system evolved to evoke pleasure when eating sugar. As I always says, “to a vulture, rotten meat probably tastes as good as ice cream sodas do to us.” It’s important to realize that sensations and feelings, good and bad, aren’t necessarily inherent in our physiology and neurology, but are themselves evolved. (Pain receptors, too, alert us to possible danger to our bodies.)

I should add that using plant compounds to repel insects and other arthropods is not a behavior unique to cats. Here are some examples cited by the authors (I love the cigarette-butt example and have written about it before):

There are other examples that nonhuman animals may exploit some chemicals emitted from other species for protection against insect pests: boat-tailed grackles (Quiscalus major) and white-nosed coatis (Nasua narica) rub fruits of Citrus spp. against themselves, chimpanzees (Pan troglodytes schweinfurthii) use sleeping platforms created from specific trees as a source of repellents , house sparrows (Passer domesticus) and house finches (Carpodacus mexicanus) living in urban habitats bring cigarette butts to the nest, and capuchin monkeys (Cebus olivaceus) anoint themselves with millipedes (Orthoporus dorsovittatus).

Finally here’s a photo of Jango, whose staff is reader Divy and her husband Ivan, trying to get to the jar of Cosmic Catnip put on the top shelf. Jango is a “positive reactor.”

h/t: Ginger K.


Uenoyama, R., T. Miyazaki, J. L. Hurst, R. J. Beynon, M. Adachi, T. Murooka, I. Onoda, Y. Miyazawa, R. Katayama, T. Yamashita, S. Kaneko, T. Nishikawa, and M. Miyazaki. 2021. The characteristic response of domestic cats to plant iridoids allows them to gain chemical defense against mosquitoes. Science Advances 7:eabd9135.

Readers’ wildlife photos

January 21, 2021 • 8:00 am

These photos come from Robert Seidel, whose notes (and the Biblical quote) are indented. Click the photos to enlarge them.

“In my distress I called to the LORD; I called out to my God. From his temple he heard my voice, and my cry for help came to his ears. – 2 Samuel 22:7”

In that vein, allow me to offer you some wildlife images, mostly of fossilized wildlife. I saw your review of the movie Ammonite early last month [JAC: here], which by co-incidence was right before I spent a weekend at Lyme Regis on the Jurassic coast of South England, where Mary Anning used to live and work and the film is set. My photos and notes:

Sunset at Lyme Regis harbour. The breakwater you see features in several films, including I believe Ammonite, as well as Jane Austen’s Persuasion.

View from top of the breakwater out to sea. I like how the stones and waves blend together in this picture.

The cliffs to the East of Lyme Regis. These are not your perfect white chalk cliffs of the Dover type, but rather more messy, with alternating layers of tough limestone and soft siltstone.

The beach in front of the cliffs, looking quite prehistoric in my opinion. This is a tidal beach which is submerged under high water. If you go out towards the East, you should take to heart the frequently posted warnings about the danger of getting cut off by the tide!

A tidal pool on the beach. Sea snails like to burrow into the soft siltstone, making it look like swiss cheese.

To the West of Lyme Regis lies Monmouth Beach, named after the ill-fated Duke of Monmouth, who in 1685 landed at this point with an invasion force in an attempt to take the English throne (). Ammonites like this are ever present along that beach.

A very large ammonite, about a foot in diameter. Smaller ammonites got washed into the empty shell as it lay on the sea floor. At the nearby town of Charmouth, there is a small museum with some fantastic specimen of such “graveyards”.

The famous “ammonite pavement” of Monmouth Beach, just a few hundred meters walk from Lyme Regis. These should be Arietites bucklandii.

Bonus photo. There is an alternative feline theory about the origin of these structures. These are four out of five of my partner’s cats. From front to back: Simba, Bella, Tonto and Katie.

Readers’ wildlife photos

January 7, 2021 • 8:00 am

Remember to send in your good photos!

Today’s batch comes from reader Rik Gern, who adds a bonus felid. His notes are indented; click on the pictures to make them larger.

I’ve been rummaging through my files to see if I could find some pictures for your Reader’s Wildlife Photos feature. It looks like my tank is also starting to run low; I think I’ve got about half a batch after this, and then I’ll have to start processing some more photos as well as taking more so that I have something to process.

This batch comes from some visits to see my mother in St. Germain, Wisconsin. As you drive farther north the trees get taller and taller, and the first two pictures are of Red Pine trees (Pinus resinosa) which are representative of the region

The woods are so full of interesting lichen, moss and wildflowers that it’s hard to walk a straight line from point a to point b since there’s always a fascinating distraction. I managed to get pictures of Smooth Aster (Symphyotrichum laeve) and Mullein (Verbascum thapsus). The broad velvety leaves of the Mullein plant are reputed to have medicinal value, but Web MD tells us that more research is needed.

Wisconsin: red pine (Pinus resinosa):

Red pine:

Smooth aster:

More smooth aster:


This part of the Northwoods is riddled with lakes, and I managed to spot some White Water Lily (Nymphaea odorata) pads on Alma Lake, but wasn’t fortunate enough to see the flowers in bloom. Maybe next time. No matter though; the pads have their own charm.

I risked life and limb to get the last photo of my mother’s ferocious companion Bella. The local humans think Bella is a house cat (Felus catus domesticus), but don’t tell her that; she’s convinced that she belongs to the genus Panthera!!!


Readers’ Christmas photos

December 25, 2020 • 11:00 am

Well, we got a veritable clowder of cat photos yesterday as well as quite a few non-cat photos—all with a holiday theme. I present them proudly as our Official Christmas Post. Readers’ captions are indented, and thanks to all the readers who participated. Click on the photos to enlarge them.

First is our own Matthew Cobb, who sent a photo and his daughter’s Christmas paintings.

Me and Ollie. He is on two boxes on top of a cupboard so I am standing on a chair…

And some lovely cards. As Matthew reports:
Ho ho ho; merry Xmas etc. These are Xmas card portraits of our cats, painted by my daughter Eve. Left to right they are Ollie, Harry and Pepper, and were cards for me, Tina, and Lauren respectively [JAC: Tina is Matthew’s wife; Lauren his other daughter]:

And Greg Mayer’s famous “philosophical cat”.
Here’s a picture of Peyton’s last Christmas, 2019.

 Greg’s first Christmas without Peyton, 2020.😥

From Robin:

This beautiful feline graces our home in all seasons (But no, she is not levitating. The table is glass. Sent by her staff, Robin Branch in Boca Raton FL, where we hear it will be a record-setting 44 degrees on Christmas morning.

From Peter Lindsay:

In response to your call for holiday-themed photos I am sending you this photograph of my now departed – but not forgotten – Bengal cat Taz. He had a particular fondness for festive table decorations, probably because they complemented his splendid markings.

From Elizabeth Grisham:

This is Gidget napping under the tree.

From reader Jez:

Here’s a photo of my daughter Ana and our cat Marcus Clawrelius (Pretentious? Moi? – although I suppose he should temporarily be Santa Clawsrelius for the Christmas holidays) taken after our tree was decorated earlier in the month.

From Reese Vaugn:

Razzberry gave us a dead rat this morning for Christmas, though somehow I doubt cats are Christians. Do you know how hard it is to stage a Cat photo?

A Christmas bird card from Colin Franks:

From Gregory James:

I don’t have a cat. And don’t really have any holiday photos including myself to offer. But I’ll offer you this “Silent Night” picture should you ever need a bit of filler material. It was taken on Good Hope Island in the Milwaukee River where a few friends gather in pandemic times to drink a beer or two, distant from one another. It has been, for my wife and myself, a balm during this year’s plague. In the summer it was light when we met. Now we meet in the dark,  with many layers of clothing. We will toast in 2021 here next Thursday evening. A better year is coming after this dark winter.

From Kevin McCarthy:

Here is Cookie who has claimed the Christmas tree. Even when it’s fully decorated, she still climbs it. I just can’t get a good picture of her like that.

From Wendy Chandler:

Here’s my Christmas cat. He died a few years ago at 19 years old.  His name was Kokomo.

From Merilee:

My granddaughter kissing an alpaca. Taken about a month ago at a local tiny petting zoo. The little monkey kissed the alpaca(?) on the mouth before my daughter could intervene, but managed to get the cute shot.

From Mark Sturtevant:

This is our Xmas tree topper. Many people will recognize it from a certain long-running sci-fi series.

From Lorraine:

I hope this photo is useable. They’re of my d*gs Ginger (brown) and Titan (black). They’re both Chihuahua mixes–Ginger also has Pomeranian and Pekinese + Ceiling Cat knows what else, while Titan is about half Jack Russell and half Chihuahua. They are both rescues from a wonderful no-kill shelter in Virginia called Paws for Seniors.

They try to take mostly senior cats and dogs who have been given up or abandoned, but they take younger ones, as well. Ginger was given up when she was 2 by an elderly man who had to move to assisted living and couldn’t take her. Titan was feral with his entire family and was trapped and brought to the shelter when he was about 8  months old. Their foster families who volunteer are the best. These guys are amazing and I’m so lucky to have found them.

From Robie Mason-Gamer:

I have always had cats, but not many pictures with a Christmas theme, so this picture is old.
The best time for cats is after the gifts are opened, when they can play in the boxes and paper. This is Braveheart, a cat-from-the-past, who looks a little like Hili. She is completely relaxed here, even though she is closely watched by leopards, a cougar, and a very menacing bear.

William and Sara Meyer sent a picture of their cat Manny:

Manny is our beautiful bruiser.  He’s a 16-pounder!  All muscle though.  And smart too.  He has a toy that I hide in the basement somewhere (in a bag, in the rafters, under an old easy chair, tied up to the ceiling) and he retrieves it for food and attention.  He and his sister JeJe are both good mousers too.  Both are rescues; Manny from a shelter and JeJe straight from the streets.  They’re the only gifts we need under our tree.

From Rik Gern, who moonlights as a clown:

Got no religion, but I’m a sentimental fool when it comes to the holidays. Nothing puts me in the spirit more than smiling children, so here is a picture of my alter ego filling in for Santa at a day-care photo shoot. I think I had as much fun as the kids that day.

From reader Simon:

This is the best I can do. Pachaca says it’s her nineteenth Christmas, the novelty has worn off, and she’s beyond posing!

From Daniel Sharp in Edinburgh:

Season’s Greetings! Here is a festive feline-themed picture. It shows me holding my cat Molly by the Christmas tree- it’s not a very flattering portrait of me, or the best picture generally, but Molly doesn’t like being held too much or for very long so it’s the best we could do!

Longshan sent a photo all the way from China:

Merry Christmas. This is Chichi, my Devon Rex cat.

From Paul Turpin:

Apollo on my lap eyeing me, thinking it’s about time for supper.

From Linda Mercer, we have a photo of her cat Bella Diva:

Find the kitty elf!

A good Jewish cat from Rachel Sperling.

This is Lloyd. He’s thirteen years old, and the bow tie was originally his bar mitzvah outfit, but it certainly works for Hanukkah as well. Lloyd is an extremely picky eater and he’s kind of whiney, but for the most part he’s a gentle fellow who easily befriends humans, dogs, and other cats (except his little sister).

A sad photo from Mark Perew:

This is Houdini.  He’s 13 and he rescued me 9 years ago.  Houdini has cholangiocarcinoma, an aggressive cancer of the bile ducts.

This is almost certainly Houdini’s last Christmas.

From Fran X:

Attached is our 5 year old Lily enjoying some Christmas Eve warmth.

From Divy, her cat Jango, “in an elf suit, paralyzed.”

From Scott G.

Today my son Marc, painted a Christmas tree to decorate the door his bedroom.  He likes squares (thank you blue tape) and multi-colored trees.  The cats are as requested.  You’ve met Kitty before (his right shoulder), but Charley is a new addition, and the focus of his life. (Kitty doesn’t seem to mind Emoji)
I couldn’t tell you about the Reindeer…

From Terry:

Ruby climbs our damn tree every day. It’s hers now 🙂

From Joe Dickinson:

Here is our previous dog, Ruby, wondering what she is expected to do with her Christmas toy.

From David Jorling:

I didn’t think I would have one for you, but just a few moments ago, lo and behold, our cat Mia was on Santa’s lap.  Had I placed her there she would have immediately jumped off.

From Zack:

Here is my submission for your website, Samwise. He is a big fan of christmas donuts.

Bryan Lepore made some art for Christmas:

 I present a piece of art I made for the holiday on which Issac Newton was born in 1642

It started by making stained glass art using paper towel and typical “schoolroom” (?) markers. Readers might try this, putting the designs in the window. It is very easy and satisfying! Use black for the lines between the colors.

The piece I show uses paper towel colored with “schoolroom” markers but I went another level with a black paper mask, using X-acto knife cutouts and punched holes. The piece is on a sunny window. The screen can be perceived in the lit areas.

From David Aylesworth:

This is Hamilton, taking another holiday nap.

Finally, a Christmas mouse from Katey:

This is not a very good picture, but it was a quick bit of fun I had with my (rein)deer mouse, Cricket. I rescued him as a baby as he has some neurological condition that would mean he would not survive for very long in the wild (he is very slow and wobbly). He is a lovely little creature, and more affectionate than any domesticated mouse I’ve ever had as a pet. I love him dearly.
To celebrate Cricketmouse you must open a hazelnut with your teeth 🙂


Readers’ wildlife photos

December 14, 2020 • 8:15 am

We are seriously low on readers’ wildlife photos, and I’m getting quite nervous. Do me a favor and send in your good photos; don’t make me beg! If I have to, I’ll play the my-content-is-free-so-please-send-some-pictures-in-return card.

Today we have contributions from two readers—some photos and a video. The photos come from reader John Egloff, who admits that they’re not the greatest pictures; but I thought they were worthwhile posting, as one rarely sees these nocturnal creatures even though many of us live among them. John’s captions are indented.

 In response to your request for more wildlife photos, I admit to being a bit intimidated by the stunning quality of the photos submitted by others that have appeared on your website.  Although the attached photos aren’t of that quality, I thought your readers might enjoy seeing these pictures of a nocturnal animal that most people never see and (as was originally the case with me) may not even realize is native to the Midwest.

Several years ago, I was living on the third floor of an apartment building on the far north side of Indianapolis that backed up to a woods and river where the wildlife was plentiful.  One evening, after dark, I was grilling on my back patio when something plopped onto the bird feeder a few feet from my head, startling me.   When I turned to look, my first impression was that a mouse, or perhaps even a rat, had jumped onto the feeder.  I watched the creature munch on sunflower seeds for a few minutes when, to my surprise, it simply leapt off of my birdfeeder, some 25 or 30 feet in the air, into the darkness.

Looking through one of my handy wildlife reference books, I discovered that what I had seen was a Northern Flying Squirrel (Glaucomys sabrinus).  Although I had (mistakenly) considered myself to be pretty knowledgeable about our local wildlife, I had been under the impression that flying squirrels were something that existed in the tropics – and certainly not in Indiana.

I soon discovered that these flying squirrels were coming to my birdfeeder every evening as soon as it grew dark.  Perhaps because we were up so high, they didn’t seem to be the least bit afraid of people, and on one occasion when my father was visiting he even (foolishly) reached out and petted one!

Because it was dark, when the squirrels leapt from my birdfeeder I couldn’t really see them “fly.”  In order to try to capture that, I set up a camera and flash on a tripod and aimed the camera into the darkness in the direction where the squirrels seemed to go.  As soon as they leapt from the feeder, I would fire the camera and flash.  Although I ended up with a lot of photos with no squirrel (or sometimes half a squirrel), I did manage to get several shots of the squirrels in flight.  The photos aren’t the sharpest because it was dark and I had to simply guess at a pre-set focal point; they’re also a bit grainy because the image has been enlarged.

Good enough; such photos are quite rare.

And now some videos from reader John Crisp:

Here’s an amazing whale encounter we had on the Fram [JAC: A Hurtigruten polar ship, similar to but smaller than the one I was on last year] in January this year. We were surrounded by an estimated 200 humpback whales (counted by the resident whale researcher). Sorry about the human noises – not just tourists, but half the crew were on the deck, so unusual was the experience! Nonetheless, the roaring of the whales is awe-inspiring. My apologies for the last 20 seconds, where I lost the plot. I should probably edit them…

John added this:

If you think it is suitable for a family show, I also have some remarkable footage of copulating lions…

I’ve asked for that footage but just got it a few minutes ago. The captions:

Lions mating in the Masai Mara. Somewhat voyeuristically, we watched for a while. During the time when a female is receptive, the pair may mate every 20 minutes and up to 50 times in a 24-hour period.

It is a noisy and apparently antagonistic affair! Watch these two:

This one shows afterglow, but no cigarettes:

And a nursing lioness:


A man and his pet cougar

October 26, 2020 • 2:30 pm

This Russian couple has a pet cougar named Messi (after the soccer player). As the introductory video explains, Messi was born in a zoo, has health problems, and requires close care.  He’s been a pet for three years now, and seems to be doing well. There’s a YouTube channel devoted to his exploits (I_am_puma), and, in this video, Messi squalls as he waits for his male staff to come home:

I’m not sure if these people feel 100% safe, but I’d be a bit scared having this giant cat around. . . .

One thing is for sure: if you take an animal like this on, it’s a huge commitment, and you really can’t go anywhere and leave it alone. For one thing, its bladder problems mean that Messi needs walkies twice a day.

A genomic and evolutionary analysis of an extinct saber-toothed cat

October 18, 2020 • 1:00 pm

A recent article in Current Biology, which you should be able get for free by clicking on the screenshot below, describes sequencing the entire genome of an extinct saber-toothed cat, thereby gaining some insight into its evolutionary history. (You can get the pdf here, and the full reference is at the bottom. If you can’t see the piece, make a judicious inquiry.)

The cat is Homotherium latidens, also known as the European saber-toothed cat (it’s also called a “scimitar-toothed cat” because its teeth were smaller than true sabertooths like Smilodon), and it probably lived from a few million years ago until fairly recently (the late Pleistocene, about 12,000 years ago). It may thus have encountered modern humans. It was about the size of a male African lion, and a reconstruction from Prehistoric Fauna looks like this (note the saber teeth and very short bobtail).

The species was also widespread: as the article below notes, “it once spanned from southern Africa, across Eurasia and North America, to South America, arguably the largest geographical range of all the saber-toothed cats.” Although it was clearly a hunter, like all sabertooths, we know nothing about its social life, or whether it was social—nor about whether it hunted by day, night, or twilight (“crepuscular”). Some of these issues were addressed by the authors using the DNA sequence.

Click to read:

The data come from a single specimen found in the Yukon and in the possession of the Yukon Government paleontology program. A section of humerus was used for dating (the fossil was about 47,000 years old), and then was crushed up to extract DNA. The authors were able to get a substantial amount of sequence from the bone, and they compared that sequence to DNA taken from living lions, sand cats, fishing cats, leopard cats, and caracals.

The conclusions about where this cat fits on the evolutionary tree of felids are pretty sound, based as they are on lots of DNA sequence. However, the conclusions about what genes may have propelled its evolution are a lot more speculative. Here are the main conclusions.

1.) The species was long diverged from the lineage that led to modern cats.  The lineage that led to this species diverged from that of all living cats a long time ago: about 22.5 million years. We knew of this substantial age from mitochondrial DNA sequencing in previous work, but it’s dicey to make conclusions about family trees from mitochondrial DNA alone. The date above is one that we can rely on, though, as it’s based on DNA divergence in the whole genome that’s been calibrated from the fossil record.

Here’s the deduced phylogeny, showing where H. latidens (in red) fits in with 17 cats and two hyenas. You can see that it diverged from living cats over 20 million years ago.

2.) There doesn’t seem to have been much hybridization between this species and the ancestors of living cats, which began diverging from each other about 14 million years ago (see phylogeny above). The authors could have detected such hybridization by finding sections of the genome that were discordant in divergence from living cats—perhaps sections of DNA that got into the saber-toothed tiger from species after the divergence of modern cats about 14 million years ago. That is, most genes would show similar amounts of divergence from the same genes in the modern-cat lineage, but a few would be much less diverged, suggesting that those genes got into the H. latidens genome after hybridization with cats that diverged much later.

They didn’t find any such discordance, suggesting that H. latidens simply didn’t hybridize with cats that evolved in the last 14 million years. For some reason this absence caused a lot of consternation for the authors.  I guess they expected to find some evidence of hybridization and “introgression” (transfer of genes between species after speciation had occurred), and they go on at great length to speculate about this absence. They mention things like low population density (so members of different species don’t meet), ecological or behavioral isolation, and so on. But the most obvious possibility, which they don’t mention, is simply that speciation between the scimitar cat and its relatives had been completed by the time they encountered each other, so that no gene flow was possible. Yes, sometimes reproductive barriers are complete, as they are now between our own species and every other species on the planet.  And this is true for lots of species. Just because hybridization is more common than we thought doesn’t mean that nearly every species occasionally exchanges genes with others.

3.) The authors found genes in the H. latidens genome that apparently underwent natural selection. The way geneticists judge this is to look for which regions of a gene have changed relative to the genes of its relatives. This is expressed in what’s called the dN/dS ratio. That ratio gives the frequency of evolutionary changes in “non-silent” parts of proteins (dN: those parts where a mutation changes the protein sequence of the gene) to the changes in “silent” parts of genes (dS: those parts where a mutation is in a noncoding part of the gene or in a third position of a “codon”, where a mutation doesn’t usually change the protein sequence).

If genes just change randomly, without selection, this ratio should be about one. If the ratio is higher than one, protein sequences are changing faster than they would under a “neutral” process in which no changes in the gene alter its effect on reproduction (“fitness”). The authors used a cutoff ratio of dN/dS of between 2 and 5 as a criterion for selection, and they found 31 genes in this range out of the 2,191 analyzed. Eighteen of these genes, potential targets for selection in this cat, are shown in the diagram below (They don’t mention what the other 13 genes do.)

You can see they fall into four general classes, and into subclasses as well, like genes affecting vision fitting into the the “diurnal” class. The authors note that while dN/dS ratios are only suggestions of what genes in the lineage of this species may have been subject to positive natural selection, they do speculate at length about the form of selection. The cats, for example, could have been selected to adapt to daylight hunting (as opposed to most cats), with consequently improved vision. Selection on “endurance” genes may have facilitated “cursorial” hunting (i.e., running down prey). And there may have been positive selection on genes known to involve social behavior—in mice. From that they speculate that this cat may have become more social and thus able to hunt down big prey in groups.

I call this kind of speculation “genomic sociobiology”, because it involves making up “just so” stories about how genetic change impacted an extinct creature. It’s fine to single out genes like this for further examination, but one has to realize that if you see selection acting on a gene affecting social behavior, for instance, it could be reducing social behavior instead of increasing it. How do we know that the ancestors of this cat weren’t social, but then there was selection on those genes to reduce sociality in favor of a more solitary lifestyle? Ditto for all the other genes. That is, showing selection itself, even if these ratios do show selection, doesn’t mean you know the direction of selection. In fact, some media outlets, like this one, have bought uncritically the notion that this study has revealed that the cat evolved to become more social.

4.) This individual, and thus its species, was very genetically diverse. That is, if you looked at the two copies of a gene in the H. latidens genome—remember, we all carry two copies of nearly all our genes except for those on mitochondria and sex chromosomes in the heterogametic sex—there was a high probability that they would be different. This “heterozygosity” would not be the case if the species were in small populations that would lose genetic variation, or in an inbred species. We can conclude that the species was genetically diverse—no surprise given how wide ranging it was.

As to why H. latidens went extinct, well, we just don’t know. Given its genetic diversity, it probably wasn’t inbreeding, and could have been stuff like competition with cats that were better hunters, a disease or parasite, climate change, or any number of things.

Overall, this is a decent paper, and a good one insofar as doing whole-genome sequencing and phylogenetic analysis of a long-extinct species. The conclusions about natural selection are speculative, and the authors realize that. If there’s a flaw in the paper, I think it’s that the authors do go on too long with the natural selection business, especially given that it’s purely guesswork based on ratios of substitutions in DNA, and because we’re totally ignorant about what these genetic changes really meant for the evolution of these cats.

Oh, and I’m disappointed that they didn’t see positive selection in “tooth genes”!


Barnett, R., M. V. Westbury, M. Sandoval-Velasco, F. G. Vieira, S. Jeon, G. Zazula, M. D. Martin, S. Y. W. Ho, N. Mather, S. Gopalakrishnan, J. Ramos-Madrigal, M. de Manuel, M. L. Zepeda-Mendoza, A. Antunes, A. C. Baez, B. De Cahsan, G. Larson, S. J. O’Brien, E. Eizirik, W. E. Johnson, K.-P. Koepfli, A. Wilting, J. Fickel, L. Dalén, E. D. Lorenzen, T. Marques-Bonet, A. J. Hansen, G. Zhang, J. Bhak, N. Yamaguchi, and M. T. P. Gilbert. 2020. Genomic Adaptations and Evolutionary History of the Extinct Scimitar-Toothed Cat, Homotherium latidens. Current Biology.

Readers’ wildlife photos

October 10, 2020 • 8:00 am

Get those wildlife photos, in, folks! (And remember, landscapes and general high-quality photos count as “wildlife”.) Today’s photos come from Kevin Elsken, who lives in Arkansas. I’ve indented his captions and IDs.

So many of your reader submitted wildlife photos are so remarkable and so well done, I use them as aspirational motivation for the photos I take. Hopefully these photos will be of interest to you and your readers.

The first three photos are of everyone’s favorite black and yellow garden spider, Argiope aurantia. Truly a gorgeous animal, though I wouldn’t want to be a small critter on the receiving ends of those fangs.

The second spider I think is a Mabel Orchard Orb WeaverLeucauge argyrobapta. Much smaller than the yellow garden spider, but almost iridescent and gleams in the sunlight. Loves to build webs in and about the compost piles—great place to catch a fly or two.

The last spider I would like to share is the Hentz’s (sometimes called Spotted) Orb WeaverNeoscona crucifera. These spiders become very active in late summer and are nocturnal, so I thought I would share photos that depict both their magnificent orb webs and their propensity to scare the beejeebers out of you at night.

On to the snake portion of the program. The first one is a RIng-necked snakeDiadophis punctatus. My brother spotted this guy on a recent bike ride, and let me tell you he may look tough but this guy was all of about 2 inches long.  According to Wikipedia these snakes are secretive and nocturnal (my 82 year old father in law has lived here his entire life and had never seen one).  While they are believed to be abundant, the author of the Wikipedia article suggests detailed research on this snake is lacking.

The second snake will get your attention: the Eastern Copperhead, Agkistrodon contortrix. This two-foot-long specimen was lazing in the middle of a country road on a different bike ride. Again according to Wikipedia, these snakes are not aggressive and their bites rarely fatal (I will take their word on the matter).

If I may indulge you with a cat story (I know, twisting your arm!):

It was the second day of July, 2019. I was sitting in our backyard reading when I became aware that the robins were raising a fuss – something was bothering them. It was then I became aware of another sound. . . mew, mew, mew, mew.  I peeked through the fence and you can guess what I saw. I called my wife and after a little work and few bleeding cuts, we brought this guy home:

He appeared to be only 5 or 6 weeks old, but we have no idea where he came from (we did check around the neighborhood). He was a little rough around the edges, hungry, but he did not have fleas but only a few ear mites. He seemed well socialized, did not mind being picked up or petted, and he has used the litter box from day one. We named him Rocket, in honor of either a) the best friend of Bullwinkle J. Moose or b) the best friend of Groot. He can exhibit characteristics of either of his namesakes.

Well he both grew and grew on us, as cats can do. Our last cat, Simba, who had graced the pages of your esteemed blog, passed away before we moved back to Arkansas. We were not sure we wanted another cat, but when a cat like Rocket shows up, what can one do?

But unbeknownst to us, about one month before Rocket appeared to us, a stray tabby with a severely broken back leg was brought to the attention of Keely’s Fund, a charity which assists pets in need in Northwest Arkansas.

With a grant from a local trucking company, JB Hunt, the one year old cat had the surgery he needed to repair his leg. And he earned a name: JB. But he had no home except for the local vet’s office where he spent nights and weekends alone in his cage.

Fast forward to December of 2019. We had gone on a trip and boarded Rocket with his vet. We went to pick him up and the technician, with a bit of a tear in her eye, told us that they had this tabby who had never really been friendly with any cats who came in, but Rocket was different, and would we want to take home a friend? Well who could resist this lovable tabby?

There were a few tears shed at the vet’s office when we took JB home, but when we sent them this photo they cried for joy:

Can Biden win with the cat-owner vote?

September 25, 2020 • 10:45 am

It’s always been my unsupported belief that both atheists and Democrats prefer cats over dogs.  For cats I have a reason: cats are themselves atheists, as they live in the moment, enjoying this life, and worship nobody. As for Democrats, well, I’m a Democrat and I’d like to think that Democrats like independent animals, while Republicans prefer sycophantic animals like dogs. But I have no data supporting either of these beliefs, and I wouldn’t stake a lot of money on them.

But R. J. Lehmann, director of finance, insurance and trade policy at the R Street Institute, got my interest renewed with this tweet (h/t Matthew). He implicitly assumed that Democrats are cat-lovers, and based an electoral college model on the assumptions that states with more cats than dogs would go Democratic, while the reverse kind of state would go Republican.

Under that scenario, Biden wins big time, getting 349 electoral votes as opposed to Trump getting 182. I’ve put the enlarged cat/dog breakdown below the tweet.

Enlargement of the above:

So how does this compare to the electoral college vote predicted now? Here’s the electoral-college map from 270ToWin (interactive on the site; click on screenshot) showing how the states are shaking out as of today:

Well, all the “safe” Biden states are cat-dominant states save Hawaii, but so are some of the safe Trump states, like Indiana and Idaho. Two of the three “likely Biden” states (Colorado and New Mexico) are dog states, with only one—Virginia—being a cat state.

I can’t see a definite pattern here in votes, though there is a pattern for animal ownership: the South is definitely more dog-friendly than the North. Since the South is also more Trump-friendly than the North, perhaps a reader with too much time on their hands can see if there’s a correlation here.

At any rate, both maps predict a Biden win, though the animal prediction is higher on Biden than the political prediction. So far, so good. Now if only cats could vote. . .