Bear talk

As Randall Munroe (writer of the amazing comic xkcd) said, "Correlation does not imply causation, but it does waggle its eyebrows suggestively and gesture furtively while mouthing, 'Look over there.'"

I immediately thought of that quote when I bumped into a fascinating study that appeared in Ecology and Society last week, about grizzly bears.  Turns out that grizzlies, which are native to the northern continental United States, western Canada, and Alaska, have been spreading lately into territory in British Columbia where they hadn't been seen before, so some zoologists decided to do genetic testing and see where those bears were coming from, and what their relationship was to other bears in the area.

So they created bear bait from a fish slurry, which is as nasty as it sounds (as researcher Lauren Henson of the Raincoast Conservation Foundation put it, "it smells really really terrible to us, but is intriguing to bears").  They put the bait in the middle of a low tangle of barbed wire, which was intended not to hurt the bears but to catch and pull out bits of their fur.  The scientists then did genetic analysis on the bear fur thus collected.

What they found was that there are three distinct populations of grizzlies in British Columbia, which seem not to have a lot of overlap.  This by itself isn't unusual -- a lot of animals have isolated sub-populations and regional variation not only in genetics, but in color, size, even behaviors like vocalization patterns -- but where it got interested was discovered because the RCF's study involved cooperation with five indigenous groups, the Nuxalk, Haíɫzaqv, Kitasoo/Xai’xais, Gitga’at, and Wuikinuxv, primarily because a lot of the traps needed to be set on Native-owned land.

And when the scientists and the representatives of the indigenous groups took a look at the results, they discovered something really perplexing: the boundaries of the populations of genetically-distinct grizzly bears followed the boundaries of the indigenous language groups in the area.

What's more perplexing still is that neither the grizzlies' range boundaries nor the regional language families coincide with any obvious geographical barriers -- large rivers, rugged terrain, areas with permanent snow cover or glacial ice.  Jenn Walkus, who coauthored the paper and is part of the Wuikinuxv Nation, wasn't that surprised.  "Growing up in a remote community called Rivers Inlet, I saw firsthand that humans and bears have a lot of the same needs in terms of space, food, and other resources," she said.  "It would make sense for them to settle in the same areas—ones with a steady supply of salmon, for instance.  This historic interrelatedness means Canada should manage key resources with both bears and people in mind."

While I don't doubt that she's right, it still is very weird to me that the settlement and dispersion patterns in humans and grizzlies would coincide like that, without there being a specific genetic barrier establishing and maintaining the boundaries.  It's hard to imagine why two human territories abutting each other, which have different indigenous ethnic background, would have any impact on where the bears are going.

Most of these kinds of regional variations in genetic makeup follow one of two patterns -- known to biologists as allopatry and sympatry.  The former is where there is a geographical barrier keeping the two populations apart; the ranges don't overlap, so the members of the two population don't mate because they don't meet.  My favorite example of this are the cute little tufty-eared Kaibab and Abert squirrels, which live (respectively) on the North and South Rim of the Grand Canyon.

[Image licensed under the Creative Commons Azhikerdude, Kaibab Squirrel, CC BY-SA 3.0]

Sympatry can be a little harder to explain, because the ranges overlap -- so there has to be something other than geography keeping the populations separate.  One of the more curious examples of sympatry is the pink salmon of western North America, which has a strict two-year life cycle.  The eggs are laid in freshwater rivers, hatch, and the young make it out to the ocean, where they spend a year -- then in the second year, the adults come back to the river where they were spawned, reproduce, and die.  But what this means is that there is an odd-year and even-year population of pink salmon.  This year, the ones spawning are odd-year salmon, and their even-year cousins are out at sea (but will return to spawn themselves in 2022).  So even though they may inhabit the same range, the odd-year and even-year salmon never mate.

The grizzlies, though, show an odder pattern; it's called parapatry, where the ranges share a border but don't overlap.  True parapatry is rare, because something's got to keep the border relatively impermeable to migration.  While in some cases it's a geographical barrier of some kind, here there's no such easy explanation.  The grizzlies are maintaining genetically-distinct populations that show no obvious reason, but -- bizarrely -- coincide with the linguistically-distinct populations of people who inhabit the same area.

So here we have a really intriguing correlation that is definitely waggling its eyebrows suggestively, but admits of no evident causation.  I'm pretty certain there is one; it's hard to imagine this being chance.  But in the absence of an explanation, it's just another of those intriguing mysteries -- and fertile ground for zoologists and ethnologists to tackle in future studies.

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I was an undergraduate when the original Cosmos, with Carl Sagan, was launched, and being a physics major and an astronomy buff, I was absolutely transfixed.  Me and my co-nerd buddies looked forward to the new episode each week and eagerly discussed it the following day between classes.  And one of the most famous lines from the show -- ask any Sagan devotee -- is, "If you want to make an apple pie from scratch, first you must invent the universe."

Sagan used this quip as a launching point into discussing the makeup of the universe on the atomic level, and where those atoms had come from -- some primordial, all the way to the Big Bang (hydrogen and helium), and the rest formed in the interiors of stars.  (Giving rise to two of his other famous quotes: "We are made of star-stuff," and "We are a way for the universe to know itself.")

Since Sagan's tragic death in 1996 at the age of 62 from a rare blood cancer, astrophysics has continued to extend what we know about where everything comes from.  And now, experimental physicist Harry Cliff has put together that knowledge in a package accessible to the non-scientist, and titled it How to Make an Apple Pie from Scratch: In Search of the Recipe for our Universe, From the Origin of Atoms to the Big Bang.  It's a brilliant exposition of our latest understanding of the stuff that makes up apple pies, you, me, the planet, and the stars.  If you want to know where the atoms that form the universe originated, or just want to have your mind blown, this is the book for you.

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

Wild West travelogue

Well, I'm back, and many thanks to my patient readers for sticking around during my two-week hiatus.  I'd like to launch this week with some observations from my travels, along with a few photographs taken by my wife (who is the amazing artist Carol Bloomgarden) and me.

Our travels this year took us out into the American West, where we spent some time in the Grand Tetons, Yellowstone, and Glacier National Park.  First of all, the natural beauty is stunning; while I like to think that we live in a part of the world that has awesome scenery (upstate New York), the grandeur of scale out there is something few places in the world can match.

The Grand Teton Mountains, from near Jackson Hole, Wyoming

There are a few additional things that have always impressed me about the American West, though.  One of them is that the Yee-Haw Attitude is alive and well, both in its positive and negative senses.  There's a feeling that personal freedom is paramount, as long as what you're doing doesn't impinge upon anyone else's personal freedom.  We did a lot of geocaching out there (and if you don't know about this amazingly weird and fun hobby, check it out here) -- and one of the caches we were seeking took us across a construction site up in Glacier National Park.  We started to cross, and were approached by two construction workers.  I expected that they were going to tell us to bugger off, that we weren't allowed there -- but they said, and I quote, "Do what you like as long as you don't mess with the equipment."

As another example of this, consider speed limits.  Near urban centers, even in the west, it's the usual 55 mph.  But as you get further out into the middle of nowhere, it goes up to 60, then 65, then 75 mph, until (in central Montana) they give up entirely.  "All right, go however the hell fast you want to," they seem to say.  "We know you're going to anyhow."

All of which is kind of funny, because our rental car was a Chevy Spark.  If you are unfamiliar with this car, all I can say is that the Chevy Spark is to cars as a pug is to dogs -- small, stubby, cute in a squashed sort of way, and not really particularly well adapted for any useful purpose.  I think that the Spark got its name from the fact that "spark" represents the energy level of which the engine is capable.  I noted that the speedometer went up to 120 mph, which was grimly amusing, because I don't think the Spark could go 120 mph if you dropped it off a cliff.  It went downhill like a boss, but going up (for example) Logan Pass involved lots of encouraging words from us and lots of nasty looks from the drivers of the cars who were in line behind us going 14 mph and who wanted for some reason to get to their destination that day.

Our Chevy Spark, recovering from a long climb

Of course, I spent a lot of time indulging in my favorite hobby, which is birdwatching.  Much of my behavior illustrated Dave Barry's contention that there is a fine line between a hobby and a mental illness.  For example, we were at the LeHardy Rapids on the Yellowstone River, a site of amazing beauty, and there was also a rainbow trout run going on, which is pretty spectacular to see.  But my wife had spotted a Harlequin Duck, a bird I'd never seen, sitting on a rock in the middle of the stream.   The following conversation ensued:

Other tourist:  Wow!  This place is gorgeous! 

Me:  Look.  There's the duck. 

Other tourist:  That water is so blue!  And the trees!  And look at all of the trout in the river! 

Me:  But there's the duck. 

Other tourist:  Yellowstone is one of the natural wonders of the world! 

Me:  I know.  That's one incredible duck.

The duck in question

Which is not to say that I didn't appreciate other stuff.  In particular, Yellowstone is an astonishing place, to the point of parts of it being kind of surreal.  The hot springs, especially, which look like some amateur artist decided to use up all of their supply of brightly-colored acrylics in painting a nature scene.  If you ever get a chance to go to Yellowstone, the must-see (in my opinion) isn't Old Faithful, but Grand Prismatic Spring, which is colored by minerals and brilliantly pigmented bacteria:

Speaking of Yellowstone, it was in the forefront of my mind to consider the possibility of eruption of the hotspot/supervolcano that lies underneath Yellowstone Caldera, largely because over the last couple of years the woo-woos have been running around making little squeaking noises about how an eruption is imminent and you can tell because the bison and elk are fleeing from the park in terror, and also because the evil US government is evacuating the place and herding everyone into FEMA camps.  Well, we saw lots of people who weren't being held prisoner in FEMA camps, not to mention hundreds of bison, and I can say first-hand that the bison showed no evidence of fleeing in terror.  Most of them were simply moseying about in terror, or even snoozing in terror.

A bison, standing around munching on grass in terror

It did occur to me, though, that these might be suicidal bison, who realized that the volcano was going to blow and decided to stick around because they were depressed and wanted to end it all.  And in fact, "Meh, fuck it" seemed to be a common attitude amongst the wildlife we saw.

Which is a good thing, because otherwise the main cause of death in Yellowstone wouldn't be people getting vaporized by a volcanic eruption, but tourists being killed in messy ways because of sheer stupidity.  I have never seen so many people who evidently do not understand that "hot spring" means "so hot that it will boil your skin off," and "wild animal" means "animal that could easily kill you if it wanted to."  A former student of mine, who has worked in the national parks, told me that just a few weeks ago, a guy tried to put his son on the back of an elk so that his wife could take a photograph, and elk bucked and kicked the father in the head.

And killed him.

We didn't see anyone get killed in Yellowstone, but it wasn't for want of trying.  We saw one woman who was jumping up and down in front of a bison, waving her arms and shouting, "Hello, bison!  Hello, pretty bison!" so that it would turn its head for a picture with her.  When it refused to cooperate, she laughed and said, "Bye-bye, pretty bison!" and scampered off.  But the worst was when we saw a bear by the side of the road...

... a grizzly bear.

Okay, I took a picture of it, but using my zoom, and from the safety of my car.  But there were dozens of people who got out of their cars.  Despite the fact that this is clearly the most dangerous animal in the park, and is unpredictable.  And huge.  Which is why you're supposed to carry a whistle and pepper spray with you whenever you hike in the area.

You do know how to tell the different kinds of bear scat apart, right?  Black bears eat a lot of fruit, so black bear poop contains seeds and stems.  Brown bear poop often contains fish bones.  Grizzly bear poop, on the other hand, contains whistles and smells like pepper.

But that didn't stop people from acting like complete raving morons, running up to the wild animals and stepping on unstable ground over boiling hot lakes, despite the multitude of signs and warnings that were everywhere.  And I'm sure that if something bad had happened, the last thing that would have gone through these tourists' minds before being mauled and/or cooked to death would have been, "Why didn't someone warn me of the danger?"

But despite all that, the trip was amazing, and I highly recommend it to any of you who like to travel.  Traveling is, I think, the most eye-opening experience out there, and the natural world is full of beautiful, stunning, awe-inspiring places to visit.

And lots of really incredible ducks.