Tiptoeing Around the Subject

I was out for a walk in the snow the other day wearing my mukluks, something I haven’t done in a while and I forgot just how much fun it is. Because they have no sole, it’s very much like walking around in your socks, but much warmer and your feet stay dry. What I like about it, however, is how much closer you feel to the world you’re walking through. I spend most of my days in hiking boots, which while they afford a great deal of support, also separate you from the ground quite a bit. Mukluks are about as close as you can get to walking through the woods barefoot, which in -20C, is not something I’d recommend.

Anyway, this little expedition got me to thinking about another set of fun words that don’t likely come up in conversation all that often. They’re words that pertain to foot posture.

Not all animals walk the same way. When we’re talking about mammals, we can usually place them into three categories: plantigrade, digitigrade and unguligrade. Today, we’ll start with digitigrade. Dogs (like the wolf, whose print in in the picture) are digitgrade. It means walking on one’s toes. In digitigrade animals, the heel is permanently lifted up off the ground. Take a close look at your dog or cat’s legs and feet. You’d notice the four toes, then the pad in the middle. That’s not the heel. Work your way up a bit and you’ll find it, a hard lump a few inches up the foot.

Plantigrade vs Digitigrade feet

Dogs, cats and other mammals like weasels are essentially walking on their toes. The reason for evolving this type of posture has to do with increasing their stride length. Pay attention next time you’re running. You’ll notice only your toes make contact with the ground. By getting up on our toes, we lengthen our stride and as a result, can cover larger distances. Digitigrade mammals do this all the time, which is why we won’t be outrunning any wolves anytime soon.

All this from a walk in the woods…

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The Joy of Obscure Words

After over 10 years as an academic, I forget sometimes that I’ve accumulated a vocabulary that most other people have never heard of. Every now and then, I’ll throw a word into a conversation or program that will leave people gazing back at me blankly, brows furrowed in confusion.

The thing is, I don’t do it to impress anyone. I use them because there just isn’t another word out there that better describes what I’m trying to say.

Subnivean is one of those words. I figured that since we’re on the subject of snow, (and we’re getting more of it as I write this), it would be a good time to bring it up.

Subnivean is a great word. Once you break it down, it’s quite simple. Sub = under, nivea = snow. Basically, it refers to anything that is found under the snow. Most of the time, it’s used to describe the habits of animals that are found living under the snow.

There are actually quite a few of them. Small mammals, like mice, voles, lemmings and shrews are too small to grow a winter coat of fur when things get cold. That much hair would make walking a challenge.  Instead, they take advantage of a rather ubiquitous source of insulation: snow. The white stuff is an excellent insulator. On days out here when the mercury drops down well below -30 degrees C, the temperature at the bottom layer of snow, right where it’s in contact with the ground, is still hovering around the freezing mark, a much more comfortable temperature for our furry little friends.

That bottom layer of snow is quite a bit different from the rest of the layers above it. It’s referred to as the pukak layer (an Inuit term) and is usually very crystaline, almost like sugar. This type of structure makes it easy for mice and voles to create an entire network of tunnels completely hidden from the hungry eyes of predators.

That doesn’t mean they are completely safe. Predators like weasels and mink can follow them down into the tunnels, while foxes and owls listen for them from above (a story for another day). Still, with lots of readily-available food, shelter and relative safety, being subnivean isn’t a bad way to be for a small mammal.

However, there are reasons to come ‘top-side’ now and then. The pukak layer can be compacted by snow collapsing or from people walking or driving snowmobiles over it, making the substrate impenetrable.  It can also get hard to breathe down there. With all sorts of critters running around in what is essentially a closed environment, CO2 can build up, making it necessary to punch a few air holes to clear things out (above).

So next time you’re out for a walk in the snow, keep your eyes peeled for the subtle signs of our subnivean neighbours.

There’s no Business like Snow Business

I love snow. I still get excited every time I wake up in the winter to find fluffy flakes coating everything in white.

That first fall of snow every year is especially fun. It’s like the world has been dusted with fingerprint power. Suddenly, everywhere you look, the ground is littered with tracks and trails winding through the forest. Looking at all these footprints from the tiniest mouse to the big (but not necessarily bad) wolf, you realize there are a lot more critters in the forest than you were ever aware of.

I actually kind of miss it when all these signs melt away in the spring. It’s nice knowing that you’re not alone on those quiet walks through the woods.

I don’t really know if it’s true that the Inuit have 100 names for snow, but they do have several and we experience all of these different forms up here. There are two types in this picture alone.  The snow floating to the ground in fluffy flakes would be called anniu, and once it settles on the surface, you would call it api.

Unlike large parts of the country, we’ve only had light flurries since the first couple big snows this winter. Personally, I’d like a bit more. It would make snowshoeing more fun, but we had a lot of moisture in 2010 and the ground is already saturated. Unless we have a very slow melt this spring, we’re going to see a lot of flooding. Still, I just can’t help but wish for just a little bit more snow.

Jack Frost Nipping at Your Nose

Frost is pretty much a defining characteristic of this time of year. Winters in the north woods get pretty darned cold. Our daytime highs have been in the -15 to -20 degrees Celsius range lately and the nights have been dipping down as low as -30. It’s the type of weather that takes your breath away, crisp and clear and, once you bet used to it, really very beautiful.

Winter nights in Manitoba can be perfect for creating what is one of my favourite spectacles: hoar frost.  On clear, cold nights, much of the earth’s heat gets sucked up into the atmosphere’s abyss, leaving the surface cooler than the air around it.  When that happens, frost forms, growing in dendrites from every available substrate.

I can still remember my first experience with hoar frost. I was a child and waking up to the world fringed in sparkling white was like walking into a dream.

While it’s gorgeous on a grand scale, it’s equally amazing when you get up close and personal, each tiny crystal spreading out into the air like tiny ferns. Each fragile structure grows as the frigid air can no longer retain the water vapour within it, depositing thin blades of ice at the tip of each branch.

So, if you’re lucky enough to live in an area that freezes from time to time, take a moment and the fragile and ephemeral beauty that is frost.