Although I have a comfortable backlog of readers’ photographs, I’ll take a break today to highlight a magnificent felid, the Canadian lynx (Lynx canadensis), and especially its gigantic paws. This beast is a denizen of northern North America; here’s its range:
First have a gander at its paws (photos from Animals Guide). Now those are some mittens! Note that the paws are furred on the bottom:
The photo below is real:
Lynxes are about 2-3 times heavier than your average housecat.
Okay, you’re probably asking yourself two questions: “Are those paws really disproportionately large compared to those of other cats?” and “If so, why are they so fricking huge?”
The answer to the first question is “yes.” Here’s a comparison of lynx with bobcat (Lynx rufus) forepaws from Naturally Curious with Mary Holland. As the notes below indicate, the two cats have about the same body size. Bobcats, of course, live much farther south than do lynxes.
Now we’ve established that the lynx’s paws are indeed relatively large. Why? It’s universally recognized that this is an adaptation to walk and run on snow more effectively: the animal equivalent of snowshoes that distribute body weight over a larger area. Some authorities add that they may also help seize prey (the lynx diet is almost exclusively snowshoe hares [Lepus americanus]), though I don’t buy that explanation since all cats are predators.
As the Mary Holland page notes:
Bobcats and Canada Lynx are in the same genus, and are roughly the same size (averaging 15 to 35 pounds), with Bobcats usually weighing a bit more than Lynx. The size of their feet is vastly different, however, and not proportional to their relative weights. A Lynx has much larger feet and longer legs than a Bobcat. Its range extends further north, which means it must be well equipped to deal with snow much of the year. A Lynx has big, furry paws, and when its feet land the toes spread way out. Both of these adaptations help a Lynx’s feet act like snowshoes, helping it to chase down food in the winter. Much of the time, this food consists of Snowshoe Hares –anywhere from 60 to 90 percent of the diet of Lynx is made up of hares. The soles of Snowshoe Hare feet are also well-furred, particularly in winter, enabling them to run on soft, deep snow without sinking in very far. Because Snowshoe Hares are extremely fast and agile (reaching speeds of 30 mph and jumping 12 feet in a single bound), the feet of any serious predator must also be well adapted to traveling on snow.
The range of the hare is almost coincident with that of the lynx, and their numbers cycle together, a well known ecological phenomenon that, while having an intuitive explanation—when hares fall in number, so do their predators, and when the hares recover so do lynxes—is in fact not fully understood. The hare range:
The famous cycle:
Back to those paws. Now it’s a reasonable explanation that the “snowshoe effect” of walking over friable snow has selected for those big mitts. After all, if you can’t run fast on snow, you can’t eat. But I wonder if it’s ever really been tested. Have they actually shown that lynx can walk and run more effectively on snow than, say, bobcats? I don’t know, but if they haven’t, then these adaptive explanations should be hedged with a caveat: “It’s hypothesized that these paws are disproportionately large because. . .”
I’ve written before about the lynx, sharing Peter Vickery’s story about monitoring wild lynxes (go look at his lynx kitten photos!), and included the amazing photo below. It’s real—I remember seeing it in the Time-Life book—and here’s the caption I gave it:
[Here’s] one of the most impressive wildlife pictures I’ve ever seen: a lynx catching a snowshoe hare, photographed by Robert Walch for the Time-Life book The World’s Wild Places: The American North Woods (1972). Look at the size of those paws!
Wikipedia notes other lynx adaptations for nomming hares:
Like all lynx, it has 28 teeth, with four long canines for puncturing and gripping. The lynx can feel where it is biting the prey with its canines because they are heavily laced with nerves. The lynx also has four carnassials that cut the meat into small pieces. In order for the lynx to use its carnassials, it must chew the meat with its head to its side. There are large spaces between the four canines and the rest of the teeth, and a reduced number of premolars, to ensure that the bite goes as deeply as possible into the prey.
Adaptations that lynx have for manoeuvring through the deep snow are feet with a large gap between the first and second toes and their big toe set at a wide angle which gives them a better vicelike grip on the snow.
Well, see for yourself. Here’s a video (possibly staged) of the classic duel between hare and lynx. Note that the hare, not having any cover, tries to escape by both zigzagging and burrowing beneath the snow. It doesn’t look to me like those big paws help the cat very much, but of course a bobcat might sink to its belly in that snow!
h/t: Wendell R.
In my next life, I want to work in a “Native Species Treatment Center”, whatever that is exactly.
Just based on my own walking-through-snow experience, I would guess that even if a bobcat could run as fast as a Lynx through snow over short distances (i.e., an ambush), it would expend a lot more energy doing it. So the adaptation would have a positive fitness value even if average run speed didn’t increase, because it may lower energy use.
Sub
Video of three Lynx passing through a backyard near Sudbury Ontario in February 2013: https://youtu.be/Pz5uzOsbvpQ
Surely, experiencing this firsthand is a taste of the sublime…
Wonderful! Nice “backyard,” too!
Your map shows no lynxes in Nova Scotia.However I swear there was a lynx at the foot of the deck steps several winters ago. My intrepid cat took off after it so I had an opportunity to compare footprints in the snow. About five times the size of the cat’s. Nobody believes me but all the characteristics were there. And the cat came back in case you are wondering.
On second look I see they are recorded in Cape Breton. I am along the north shore in NS proper up in the hills.
Magnificent! I wonder if lynxes could be domesticated. Probably not, because even a domestic cat thinks he’s the king of world.
Lynx have been raised in fur farms, like those silver foxes in Belyaev’s famous domestication experiment. I expect the animals in the farms have undergone some unintentional selection for docility, just as the foxes used to start that study did.
I have never seen a Lynx, but I have seen many bobcats, and all of the bobcats I have seen (western US) are noticeably smaller than the lynx being carried out of the Native Species Center, not the same size as claimed. Is this lynx unusually big?
There may be regional differences in bobcat size, with larger bobcats tending to be up north. Of course larger size is trend for mammals living in the cold.
There is also the fur-poofyness factor.
Is it possible that the lynx descended from the bobcat? The lynx lacks a long tail, which one would think would be very helpful when changing direction. Perhaps it never re-evolved a longer tail because the genes which might encode it have been lost in the bobcat?
Both are members of the lynx genus and probably descended from a common ancestor.
They share a common ancestor, of course.
http://www.timetree.org/search/pairwise/canada%20lynx/bobcat
Of course. Everything does.
And the common ancestor is recent enough that hybridization is still possible.
http://messybeast.com/genetics/hyb-lynx-bobcat.htm
I had always confused the Lynx and Bob Cat. Now, at last, I think I’ve got them strait.
Oooo. Those paws are totes amazeballs!
Me too, confused them and am amazed.
Speaking of amazeballs, looks like he’s getting in a few lyx.
The larger feet should provide an advantage, but it should also be tested for example by measuring how fast a mammal runs in the snow, then putting on artificial lynx feet to see if it now runs faster. That should take care of many of the variables in making comparisons.
Bigger feet should make a difference b/c the larger feet will displace more snow and that slows down how fast the feet sink into the snow. They may even sink ~ as far as smaller feet, but by sinking more slowly there would be less loss of speed.
I wondered if lynx feet are larger on the skeletal level, or are they pretty much just larger by being more furry. This mounted skeleton seems to confirm that they got big feet even w/o the fur: http://reiji-san19.deviantart.com/art/skeleton-of-a-lynx-302882241 You can also see the legs are pretty long, like the information above says.
Even if they don’t let the lynx run faster in snow, they may be positive adaptations if it lets the lynx run the same speed with less energy expended. So not as easy to test as you may think.
Your proposed experiment is performed by millions of bipedal mammals every winter at ski resorts around the world.
It sure seems to be an adaptation for snow. We know that when it snows up north it just piles up and does not melt much all winter. The fresh dry snow on top, you would sink in but the older snow underneath is another issue. The Lynx may be plowing thru the top new snow but the foot or two below – the big feet hold up.
When I heard the first couple notes of the music, I momentarily thought it was going to be this. Would have been very mildly apropos.
If lynx hunt by grabbing with their paws rather than with their mouths they may also benefit from the more accurate sensation that large, fluffy, well insulated paws would bring.
What was it that prompted this post?
I only ask because the second part of a Sky1 documentary on Big Cats is on right now and its about the Canadian Lynx
Very strange coincidence!
If anyone in the UK has Sky1 then this series is well worth a watch
I did a report on bobcats last semester & did read that bobcats are prevented from properly hunting in 15cm of snow. Also interesting was that bobcats are allegedly more aggressive than lynx & will displace lynx if allowed. That brings into question whether global warming will allow bobcats to displace Canadian lynx. I’m sorry I can’t provide links (no pun intended) for my sources but I got info from library books from the University of West Georgia that seemed legit.
Love the scraggly ruff-like hairs on its chin. Speaking of chins, though I had never sniffed any kitteh paws until recently prompted ( and not really smelling anything then) , I will admit to loving kissing kitteh chins🐱
That is a mightily impressive Cat.
Having watched the clip a few times it almost looks as though the Lynx is kind of swimming through the snow with its forelegs during the attack.
Great story and especially pics! Think I’ll stick with the intuitive–snowshoe–hypothesis until discrediting data appear… 😉
I know rationally that this animal is a noble predator, a hunter of small game and a wild beast that could rend me limb from limb given the right motivation… but my stupid brain can only think “I want to pet the kitty!”