Tuesday, January 18, 2011

Smart, Aggressive And Not Always Entirely Honest

Since the new year I’ve been home a bit more often during the day, seeing as… well, I’ll get to that in the next post, which has given me an opportunity to see the comings and goings of various creatures in the yard- mainly birds- during the day. Last week one morning this big Scrub-Jay showed up on our deck.

WSJay1 Tangent: One of the weird things about Winter, assuming you work a full-time job, is that a whole week can pass without you ever seeing your home in the light of day. You leave when it’s dark and come home when it’s dark. Sometimes you’ll wake up on a Saturday morning in January, look out the window, and think, “Oh yeah- this is where I live…”

The Western Scrub-Jay, Aphelocoma californica, is a super-easy bird to ID, as it’s pretty much the only blue bird in Salt Lake Valley in the winter. It has a distinctive call, arguably the harshest of corvid squawks: a razor-sharp, scratchy, climbing note that instantly catches your attention. When it shows up in the yard- never staying more than 5 or 10 minutes- it immediately disrupts the social equilibrium around the feeders*, sending juncos, siskins and finches scattering.

*I described the Winter “regulars” at my feeders 2 years ago in Bird Feeder Week. Man, was that a great week or what?

Scrub-Jays are birds of woodlands. In Utah they’re most often found in either Piñon-Juniper or Scrub Oak. This time of year you’ll almost always come across a couple if you go poking around on any of the foothill trails across the street form the zoo, or up around the Death Climb. Aphelocoma, the Scrub-Jays, includes 5 species, all native to North America, but the only other one* you’re likely to see in the US is the Florida Scrub-Jay, A. coerulescnes, native to, yes that’s right, Florida.

*The Island Scrub Jay, A. insularis, is endemic to Santa Cruz Island off the California coast.

The Western Scrub-Jay is divided up into a whole bunch of subspecies, grouped broadly within 2 clades, (which may in turn get reclassified as 2 distinct species sometime in the near future): one inland and one in California.

Side Note: This might sound similar in some ways to the division between Black-billed and Yellow-billed Magpies; the Sierra Nevada/Great Basin constitute a formidable barrier to migration. But while Magpies came over from Asia some 3-4 million years ago, Scrub-Jays are “New World Jays”, thought to have migrated Northward from Central America.

One of the interesting markers of A. californica subspecies is bill morphology. Subspecies that live in Piñon-Juniper woodlands have straight, thin bills for reaching in between cones scales to grab Piñon seeds, while those that live around Oak woodlands have slightly broader, more hooked beaks (better for working with acorns). Our subspecies here in Northern Utah, A. californica woodhouseii woodhouseii (sometimes called Woodhouse’s Scrub-Jay by bird geeks) has sort of an in-betweeener beak: straight but heavy, with a slight hint of a hook at the tip.

Acwwoodhouseii Bill In any case, it’s easy to dismiss Scrub-Jays as somewhat unremarkable in that compared to other “Pine Birds” their capabilities can seem rather unimpressive. Pinyon Jays for example can carry 0.6 oz worth of nuts in their mouth/esophagus. Clark’s Nutcracker- the champion pine bird- can carry over a full ounce- over 20% of its body weight.. Guess how much a Scrub-Jay can carry? 0.05 oz- less than 2% of its body weight. And it barely limps along with that load. A fully-loaded A. californica will fly no more than 1/3 mile to cache nuts, reaching a top speed of no faster than 18 MPH.

Pine Bird Stats The Pinyon Jay carries its load up to 6 miles, at speeds up to 26 MPH, and Clark’s Nutcracker up to 18 miles at up to 29 MPH. Even Stellers Jay- not a nut or acorn specialist- can manage up to 2 miles with a 0.2 oz payload at up to 22 MPH.

Side Note: An interesting corollary to these figures is the role- or rather lack thereof- played by Scrub-Jays in the modern-day distribution of Piñon pines*. monophyllaneedles35 Piñon pine has steadily expanded Northward across the Great Basin since the end of the last ice age, only reaching its present range within the last few thousand years. Piñon doesn’t occur on the floors of Great Basin valleys- only on mountain slopes. The principal agent moving it between disjunct ranges was pine birds, who spread the nuts via caching. With such a dismal loaded flight-range, the Scrub-Jay has likely played little role in its expansion to new ranges.

*I’ve covered Piñons extensively in this project, most notably in this post and this post. Man it is like I have a post for everything.

Stellers Jay’s loaded flight range is also pretty modest. It’s a bird of higher altitudes, and an infrequent visitor to Piñon-Juniper Woodland. When it does collect piñon nuts, it most often caches them at higher altitudes, unsuitable to piñon growth. But as temperatures rose following the end of the last ice age, its slightly-too-high seed caches may possibly have helped piñon expand up-slope within ranges where it was already established.

Scrub-Jays’ bills aren’t strong enough to pry apart the scales of unopened piñon cones. Instead they pick seeds from already opened cones, or wait for other, stronger-beaked corvids, such as Pinyon Jays, to open them for them, whereupon they harass them, drive them away, and make off with the goods.

What Scrub-Jays have going for them is their big brains. We covered the high intelligence of corvids when we looked at Magpies last Fall. Scrub Jays aren’t champion tool-makers, aren’t known to recognize themselves in mirrors, and certainly don’t display the phenomenal memory and navigational skills of Clark’s Nutcracker. But they appear to have both strong episodic memory and exceptional social awareness.

Episodic memory is the memory of autobiographical events and context, including time, place and emotion. In experiments Scrub-Jays have been placed in 2 different cages- one in which they were fed, the other in which they weren’t. Later the same jays were given the access to, and the opportunity to cache food items in, both cages. They overwhelmingly cached food in the cage in which they’d been hungry.

Extra Detail: Episodic memory is one of the 2 forms of declarative memory, which I described in this post. The other form of declarative memory is semantic memory, which is information or knowledge independent of personal context or relevance.

Scrub-Jays remember not only events, but others present at those events. When Scrub-Jays cache food items in front of other Scrub-Jays, they’ll frequently return later and move the items multiple times to avoid pilferage. They even appear to be able to keep track of specifically which individual birds saw them cache at which location on which occasion. Clark’s Nutcrackers, on the other hand, as brilliant as they are navigationally, seem to be utterly clueless to potential theft, happily caching away in front of Scrub-Jays and other thieving corvids.

Side Note: Lest this post make Scrub-Jays sounds like scoundrels, I should mention that they exhibit strong pair-bonding and parenting habits. In fact, when Scrub-Jays cache in front of their “spouse”, they only re-cache about as often as if they’d done so unobserved; their spouse is clearly on the same “team.”

Florida Scrub-Jays BTW, seem to take social cooperation even further, with young adults helping parents to cooperatively raise younger siblings. Family members also collaborate to take regular “watches” looking out for hawks, snakes and other predators. Similar cooperative breeding efforts are displayed by Western Scrub-Jays down in Mexico, but not here in the Western US.

But what’s interesting about this re-caching behavior is that it’s exhibited only by Scrub-Jays who have experienced cache-theft directly. By which you probably think I mean that once they’ve been robbed, they figure it out, smarten up and start caching in private or re-caching if they cached while observed by other Scrub-Jays, right? Wrong. What I meant was specifically the opposite: Scrub-Jays don’t re-cache until they themselves have robbed other birds’ caches. The experience of having observed another bird caching, and then they themselves having robbed that cache, clues them in that other Scrub-Jays watching them will likely figure out the same schtick. This learning-process suggests that Scrub-Jays, like us, have evolved a “theory of mind”- the ability to attribute knowledge, intent and desire to others. What does so-and-so know? What is he or she likely to do with that information?

WSJay Scoot cut Humans seem to develop a theory of mind around age 4. Before this time, children fail “false belief” tasks. For example, a child is told a story with 2 characters. Character A puts something- a toy, a ball, whatever- in a basket, then leaves the room. Character B moves the object from the basket to someplace else- say a box. Character A returns, and the child is asked where Character A will look for the object. Up until about age 4, most kids get the answer wrong. So in other words, the Scrub-Jay is- in at least some ways- smarter than a 3 year-old kid.

Side Note: Autistic kids over age 4 usually still fail this test, which backs up my previously-expressed Half-Baked Theory that Clark’s Nutcracker is essentially an autistic corvid.

This social intelligence makes possible all sorts of deception. Scrub-Jays and other corvids, such as crows and ravens, routinely move caches, make false caches, and cache inedible items to throw off would-be thieves and competitors. In other words, they-deliberately and with forethought- lie. How “human” is that?

You may object that simply misleading is not lying, that a lie is a specific statement of falsehood, and corvids lack the level of language to be able to explicitly state such falsehoods. But I disagree; I’ve always felt that the nature of a lie is in intent, not words. Most of us are uncomfortable directly stating a falsehood, but we all “tell” little partial lies of omission all the time. When we host a party, we don’t call or email our friends whom we’re not inviting to tell them of the event. In business we don’t notify our competitors before calling on their clients, and we don’t usually tell our bosses before interviewing for another job. Often these lies of omission are harmless. Sometimes, as in the case of the uninvited guest, we tell ourselves it’s for the benefit of the person to whom we are “lying” (although the real reason is just as likely to be our own cowardice or conflict-avoidance…) Then there are lies of omission that might- or might not- cause harm, such as when your new boss fails to volunteer why the 2 people to hold your job before you quit, or when a manufacturer fails to disclose certain product information…

Part of being an intelligent social animal with a well-developed “theory of mind” is constantly deciding what information to share when with which individuals. To simply describe this information we share as “truths” or “lies”, while comforting, doesn’t always describe things the way they really are.

All of which brings me, in a rambling and roundabout way, to my point, which is this: there’s a piece of information, an aspect of this project, which, while I haven’t misstated or misrepresented, I haven’t been entirely forthright with you about, and it is this “lie of omission” about which I will come clean in the next post.

Next Up: ABC in Perseus.

Note About Sources: Thanks to my friend and fellow nature-blogger KB for help accessing several of the sources for this post. Scrub-Jay caching, pilfering and memory info came from Food Caching Western Scrub-Jays Keep Track of Who Was Watching When, Joanna Dally et al, Social cognition by food-caching corvids: the western scrub-jay as a natural psychologist, Nicola S. Clayton et al, The Mentality of Crows, Convergent Evolution of Intelligence in Corvids and Apes, Nathan J. Emery et al, and The rationality of animal memory: Complex caching strategies of western scrub jays, Nicola S. Clayton et al. General info on Scrub-Jays came from Kaufman Field Guide to Birds of North America, the Cornell University Lab of Ornithology All About Birds website and Wikipedia. Info on episodic memory and theory of mind (including the example story) came from Wikipedia. Figures on flight loads, speeds and ranges of various pine birds came from Made For Each Other: A Symbiosis of Birds and Pines, Ronald M. Lanner, and info on the historic range expansion of Piñon pine came from The Desert’s Past: A Natural Prehistory of the Great Basin, Donald K. Grayson.

Wednesday, January 12, 2011

Birds, Hearing and Ears

Note: This is my 400th post. It’s just a number, but kind of a big number, and certainly far more posts than I ever intended this project to include. This post is around 3,800 words. If I guesstimate that the average post is ~3,000 words long, that’s ~1.2 million words*, which is roughly 10-15X the length of an average novel.

*Probably around half of which are tangents.

The other night I woke up with a start in the middle of the night* and had a heck of a time falling back to sleep. It was still early enough (2:30AM) that it wasn’t worth getting up, and so I tossed and turned for a while. As I did so I noticed that I’m always hearing things. Winter nights in our neighborhood are super-quiet- no birds, no crickets, windows shut tight, but it seems like I’m always hearing stuff: Awesome Wife’s breath, the click of the thermostat, the air moving through the heating vents, even my own pulse as my head lies sideways on the pillow. You can close your eyes, but you really can’t ever “close” your ears.

*Yes, like many middle-agers, I often awake at odd times. But this was different: it was “dream shock”. You know, when you’re so startled or alarmed or scared in a dream that you wake yourself up.

Oh, you want to know what the dream was? OK, I’ll tell, even though it’s kind of personal and embarrassing and borderline TMI, because that’s just the kind of blog this is. It was a Pee Dream. You know, one of those dreams where you have to pee real bad and you’re looking for a place to go, but can’t manage to find a bathroom? I dreamt I was waiting my turn to start in a race. The race was- I am not making this up- a Night Snowblade Race. Excell_snow_blades_skiboards Remember snowblades? They were like these super-short mini-skis that were briefly popular in the late 90’s, and you could ski downhill on them or skate along on the flats. (I tried a friend’s once- total blast.) Anyway, racers were heading out on these things, with headlamps, one after another at regular intervals, like some kind of night-time-trial. I looked up on this open, snow-covered hillside (the race was somewhere up around Kimball Junction), and saw little dots of headlamps moving downward on the descent. My turn was coming up, and I realized I had to pee, so I thought I’d just step a ways off in the bushes (it was dark, you know) and pee real quick. But I stepped away, and was still in view, so stepped a little further away, and then a little further, and all of a sudden I was standing along someone’s driveway. But the house was dark, and I thought, “I’ll just pee in their bushes real quick…” and I was just getting ready to go and then all of a sudden the garage door started opening and a car pulled into the driveway and someone was yelling at me and I was like all panicked and that’s when I woke up.

Visually-oriented as we are, we’re always hearing, but mostly half-consciously. We tend to think about our own hearing when we hear something significant- music, birdsong, waves crashing- but largely ignore it otherwise. But if you stop and listen, say right now- in your home, office, wherever- hearing is really remarkable. You’re constantly receiving all sorts of information- machines running, people passing, cars outside, planes overhead. We get all sorts of cool details about these things- presence, direction, speed, distance- all the time, without even looking, without focusing, without even having to turn our heads. We’ve all seen shows or read stories about psychics, telepaths, or people with special powers who can somehow sense or detect things that can’t be seen. But with hearing, all of us have a sense that’s far more real, more precise and more powerful than any Yuri Geller trick.

Over the course of this project I’ve kept bumping into hearing, but never really gave ears much thought. But the research I did for the All About Heights post got me curious about them, and then the Owl post got me wondering (again) about birds’ ears, and so I started reading and one thing lead to another, and, well it turns out that ears are not just way cool, but have an absolutely amazing story.

In a side note to the heights post I wondered about balance in birds, and whether the ear played a similar role in birds- specifically a vestibular sense- as it does in mammals. The short answer is yes, but the story behind it is a bit more complicated. But first, to tell the story, we have to know just a bit about the human ear.

All About Ears

You’ve probably heard that the ear has 3 major chunks: the Inner, Middle and Outer Ears. The outer ear is the only part you see, and consists of the pinna and the ear canal. The pinna is the part on the outside that your junior high school girlfriend/ boyfriend stuck their tongue inside when they gave you a Wet Willie*. The pinna is strictly a mammal thing; birds, reptiles and amphibians don’t have them.

Mammal Ear1 The role of the pinna is twofold: to amplify the sound delivered to the middle ear, and to provide information about the direction of sound. Many mammals of course have really big pinnae (in relation to their head/body size) which play an important role in detecting prey, predators or (in the case of bats) the physical world around them. Human pinnae are proportionally much, much smaller and for a long time it was assumed that they were vestigial, playing no real role in our modern-day hearing.

*Over the years, I’ve come to believe that there are 3 categories of human sexual foreplay. The first is things you used to do when you were in high school, and still do with your spouse/partner 20+ years later. The second is things you used to do when you were in high school, and now no longer do, but kinda-sorta-sometimes wish you still did. The third is things you used to do when you were in high school, no longer do now, and can’t for the life of you remember why you ever would have wanted to do such a thing. For me, Wet Willies are firmly in the third category.**

**Along with hickies.

But it turns out that our pinnae do help our hearing. Between 1.5KHz and 7KHz, the pinna and ear canal amplify sound by between 5 and 20dB. Above 6KHz, the pinna plays a significant role is helping to determine the direction of sound.

HearingRanges4 Extra Detail: As we saw in the bat post, human hearing ranges from about 20 Hz to 20 KHz. Human speech generally runs between 80 and 400 Hz. Middle C is 261 Hz. The highest note on a piano is a little over 4KHz, which is BTW roughly the same frequency as a chainsaw or fingernails on a chalkboard*.

*Unfortunately, I was unable to find out the frequency of a chainsaw slicing through a chalkboard. But man that’s gotta hurt.

Side Note: But there is a part of the human pinna that is vestigial, Dtubercule1and which appears in about 10% of humans, including- yes, that’s right- me!* It’s called Darwin’s tubercule, and is a slight thickening/protuberance of the rim of the pinna, about 2/3 of the way up (2 o’clock on the left ear, 10 o’clock on the right.) it corresponds to the point of pointy-eared mammals, and is believe to be a vestigial remnant of our presumably pointy-eared ancestry. Sometimes it’s more of a bump or protuberance pointed away from the ear canal, creating an almost Spock-like effect.

*I have it on the right ear only.

Birds also have an outer ear (pic left, not mine), ear_ghowhich also has an ear canal, but does not have a pinna. Instead birds have evolved special feathers, called auricular feathers, which protect the canal opening, as well as direct and amplify sound into it. Reptiles don’t really have an outer ear. In those with external ears (many reptile ears are internal-only) the tympanic membrane, which marks the beginning of the middle ear, is often visible on the side of the head.

Bird Ear1 At the opposite end of the ear-assemblage is the inner ear, set inside the skull, and constructed out of the hardest bone in the human body (diagram left, not mine). It has separate sections for hearing and balance. The hearing section is the vestibularsystem4cochlea, which consist of 3 fluid-filed chambers lined with specialized hair cells. The motion of this fluid is directed by vibrations received by the outer ear and transmitted to the cochlea via the middle ear- which we will get to momentarily- and detected by the hair cells, which then transmit this information, via the cochlear nerve, to the brain, where it is interpreted as noises.*

*Or perhaps images, if you are a bat.

The balance section is a fluid-filled chamber called the vestibule, which branches off into 3 semi-circular canals. The canals, which are also fluid-filled and lined with current-detecting hairs, are orthogonal to one another, so as to detect motion and position in 3 dimensions, which is transmitted to the brain via the vestibular nerve.

All amniotes* have this same basic inner ear structure, which we apparently inherited from a common amphibian ancestor. All amniotes use the inner ear not only for hearing but for balance. It’s suspected- but not agreed**- that the amphibian ear may have evolved out of a sense organ called the lateral line in fish, which consists of a line of pressure receptors- called neuromasts- than run along each side of the fish. The lateral line enables fish to detect small disturbances in the water, and is why large schools of fish are able to maneuver elegantly en masse in close quarters without bumping into each other.

*Amniotes = “Reptiles on up”, or reptiles, birds and mammals, but not amphibians. Technically they’re tetrapod vertebrates with land-adapted eggs. The egg can be external, or internal- like the amniotic sac of a mammalian fetus.

**An alternative hypothesis is that the neuromast and the inner ear evolved out of the same ancestral structure, which might-could-maybe have been some sort of statocyst-like thing. A statocyst is a balance organ found in some aquatic invertebrates, including various little plankton-y things and, our old friends, the echinoderms. It’s a little fluid-filled sac lined with sensing-hairs and with a little mineralized sand-grain inside called a statolith. Kind of like a teensy 1-flake snowglobe. Statocysts BTW are the reason that Brittlestars and Seastars (which I blogged about in this post)- which do not have brains- can tell when they’re upside-down (which they want to avoid, so as to deny predators an open shot at their soft juicy undersides…)

Extra Detail: Just because we all share the same basic inner ear structure doesn’t mean it’s stopped evolving. Our cochlea for example is coiled up like a little snail shell, very much unlike that of birds or reptiles. The coiling- which may be an adaptation to support longer sensing hairs- occurred sometime after our ancestors split from monotremes, but before we split from marsupials. Kangaroos have it, platypuses don’t. Another evolved feature is the presence of both tall hairs and short hairs inside the inner ear, something both mammals and birds- but not reptiles- came up with. In our ears the short hairs have “lost” their wiring, and don’t transmit information neurally. Instead they function by moving in response to current in the fluid, setting up motions that are in turn detected by the tall hairs. In birds short hairs perform a similar mechanical function, but also still transmit information neurally themselves as well.

OK, stick with me- we’re almost to the good part. The middle ear begins with a thin membrane- the ear drum- blocking the end of the ear canal. Vibrations received on this membrane are transmitted by a series of 3 connecting, successively smaller bones- the malleus, incus and stapes- through the air-filled chamber of the middle ear to the inner ear.

Mammal Ear2 These bones- together called ossicles- get successively smaller going from outermost (malleus) to innermost (stapes) such that the “footplate” of the stapes has a surface area only a small fraction that of the eardrum. The ossicles are arranged in a lever-like formation, the action of which serves to significantly concentrate and amplify the sound delivered to the inner ear.

The middle ear of a bird or a reptile is set up more or less the same way, with one glaring exception: their ears have but one ossicle- the stapes-equivalent- which is called the columella. Because of this difference, mammalian ears are capable of detecting much higher frequencies than bird or reptile ears. (Finally, something we do better than birds!)

Bird Ear2 So why don’t bird and reptile ears have 3 ossicles? Did they lose them or something? Actually they still have them, but they serve their original, reptilian function, that of lower jawbones.

Fish don’t have middle ears. The stapes/columella- in all amniotes- is a modified bone from a fish’s upper jaw. Fish have several bones in their lower jaws which in amniotes have fused together in different ways. In birds and reptiles, most of these bones have fused together into what is called the mandible. In mammals, some of the these same bones have been fused together into our modern lower jawbone, but 2 of them have moved back and shrunk until they were tiny little things set way back in our heads- the 2 additional ossicles (malleus and incus).

Extra Detail: In some reptiles the mandible is not completely fused, and the extra bones make possible a double-jointing of the lower jaw, as is the case with many snakes. (Snakes don’t actually “unhinge” their jaws; they just have a joint that we don’t.)

Side Note: There’s kind of a cool corollary here. When a bird opens its mouth, the hinge of its jaw is in a fundamentally different place in its skeleton- located where we would think of as the middle of our middle ear. What does it feel like when a bird opens its mouth? Does it feel like it feels to us when we open our mouths? Or does it feel more akin to popping our ears?

Now at this point, seeing as mammals evolved from some kind of ancient reptile, you may be wondering how the middle ear could have evolved from 1 to 3 ossicles. How could an intermediate, or transitional form possibly have functioned? The answer is that the middle ear evolved independently in mammals and reptiles. And birds. In fact the middle ear appears to have evolved independently at least 4 times among amniotes, following 4 different basic designs. It evolved once in mammals (or maybe proto-mammals or mammal-like reptiles/synapsids). It evolved separately in archosaurs (superset of dinosaurs) along a design that is present today in birds and crocodilians. It evolved another way in turtles and tuataras*, and a fourth way in lizards and snakes**.

*I didn’t know what they were either. Tuataras, Sphenodon sp., are a genus (2 species) of couple-foot-long lizards native to New Zealand that are, uh, not actually lizards. Meaning that if you or I saw one, we’d say “Hey, that’s a lizard”, but zoologists don’t consider them as such. Their teeth, heart, lungs, brain and mode of walking are all different. They’re sometimes called “living fossils”, as they are the sole survivors of a once-diverse order, and are thought to be anatomically more similar in some respects than other modern reptiles to early amniotes. They have ears, just not external ones.

**It’s actually a little more complicated than this. Turtles and tuataras share a design which probably evolved first, then after the ancestors of lizards and snakes branched off from tuataras, they evolved a significantly different middle ear. The turtle/tuatara middle ear architecture is sort of the stem-reptile default, a structure which they share, even though tuataras are believed to be more closely-related to lizards and snakes than they are to turtles. Got it?

So the middle ear evolved multiple times among amniotes. That’s cool, but it’s really not amazing. At this point in the project we’ve seen countless examples of parallel evolution, from eyes to CAM to C4 to wings to pale skin in humans. But there are 2 cool things about the parallel evolution of the middle ear: a little cool thing, and a Way Freaky Cool thing.

The Little Cool Thing

The little cool thing is the contrast between eyes and ears among amniotes. Think about it. We’ve talked a lot about eyes and vision, and the various differences between bird and mammal vision. But even with all of the remarkable differences between our eyes and bird eyes, the structure of our camera-style eyes is the same basic thing, working on the same principles, and it’s the same basic design we’ve all had since long before our lungfish-y ancestors first flopped up out of the water. But our middle (and outer) ears have evolved completely independently, with significant fundamental structural differences. Imagine if our amphibian ancestors had come up onto land with no eyes, and then the ancestors of birds and mammals evolved them completely independently along fundamentally different structures. Like if birds evolved camera-style eyes and we evolved compound bug-eyes or something. That’s more or less what did happen with the middle ear.

The Way Freaky Cool Thing

But the Way Freaky Cool thing is the timing of the evolution of the middle ear. Middle ears- all four versions- evolved during the Triassic, between 220 – 250 million years ago. That sounds like a huge range of time until you put it into context. Amniotes appeared at least 340 million years ago. Synapsids (mammal-like reptiles) branched off not much later (~324 million years ago) followed later by the archosaurs. And earlier, amphibians were present for maybe 10 or 20 million years before amniotes came about.

Middle Ear evo So in other words, 4-legged critters were running around on land for something like a hundred million years during which time everyone heard like crap. Then, “suddenly”, over just 30 million years, middle ears evolved independently multiple times amongst different groups of now-way-distantly-related critters. It’s like, for some reason, hearing well- and in particular hearing higher frequencies well- became really important. Why?

Tangent: My wild guess is that once one group of amniotes got decent hearing, it became a huge competitive advantage for both predators and prey. But what’s interesting- if that’s the case- is that that one group to evolve a decent middle ear first didn’t just replace all the other groups relatively promptly, but that the other groups managed to come up with the same gizmo in relatively short order. In any case, it’s weird to think that for like a 100 million years, there were all sorts of animals running around, and none of them ever heard leaves* rustling in the breeze**.

*Well, more like fronds I guess back then.

**Not counting bugs of various sorts, who have a whole different array of “ears” and natural history of hearing.

Just because they don’t hear as high as the highest-hearing mammals doesn’t mean birds don’t have great hearing. The asymmetric supersensitive ears of the Great-Horned Owl are just one example.

Side Note: Now’s a good time to return to a topic that’s bugged me for a while, and which I’ve touched upon a couple of times in previous posts: Why don’t birds rule the skies at night? Or in other words, why don’t they do the bat thing? Maybe it’s the high-frequency hearing limitations of their single-ossicle ear-architecture. There are echolocating birds, but their echolocating frequencies are significantly lower than those of bats. Oilbirds for instance echolocate at frequencies between 1 and 15KHz, swiftlets between 4.5 and 7.5KHz. Using such relatively low frequencies means longer wavelengths, and so neither can effectively echo-detect anything smaller than about 6 cm, which means that they can “see” walls and such, but not flying insects. No bird is known to be able to detect any frequency higher than 29 KHz. Bat-sonar ranges from 11 – 212KHz.

Of course hearing isn’t just in the ears. Just as our brains turn input from our optic nerves into images, they convert input from our cochlear nerve into sounds. And it appears that bird brains may process their input differently than ours do. Birds recognize sounds more quickly than we can. We need to hear a note for at least 1/20th of a second to recognize it. Birds can do so in just 1/200th of a second, which means they can hear multiple notes where we might hear just one.

Pitch

Another cool thing about birds and hearing is that they seem to have something like perfect pitch. Perfect pitch is the ability to recognize a specific note at a specific frequency- for example you hear a note on a piano and say (with no other tonal context) Oh yeah, that’s middle C (261 Hz). Or to just sing middle C. Very few people can do this- maybe 1 in 10,000.

Extra Detail: It’s unclear whether there’s a genetic basis for perfect pitch. Early musical instruction and training appear to help. Native speakers of tonal languages, such as Chinese and Vietnamese, seem to be a bit likelier to have the ability.

But birds just seem to nail it, hitting the right note every time. They generate the right notes, and seem to recognize the right notes as well. How do we know that they recognize the right notes? Because they seem, conversely, to lack relative pitch.

Relative pitch is the ability to recognize the relative intervals between different tones, regardless of pitch. Syrinx Expand-O[9]Or in other words, a melody. For example, suppose I play Twinkle, Twinkle Little Star* on the piano, starting at middle C. Then let’s say I play it again, starting one octave lower. Or higher. Or maybe I just drop down 2 notes and start the tune at middle A. In all cases, you’ll recognize the tune as the same melody. But a bird won’t; it hears them as different tunes.

*Then again, my own relative pitch leaves something to be desired. I was over 40 before I realized that Twinkle Twinkle Little Star and the Alphabet (ABC…) Song were the same melody. I mentioned this last week to Awesome Wife, who pointed out that it was also the same melody as Bah-Bah Black Sheep…. which I never realized until right then.

Birds do some cool things with hearing. In many species, chicks communicate with their parents before they hatch. Some chicks, such as pelicans, actually complain if too hot or cold while still inside the egg, while others, like quail, chirp to synchronize their hatching. Birds’ ability to discern notes quickly helps them to recognize the calls of parents and chick, which is critical in species that nest in huge, noisy colonies, such as gannets.

So while bird ears and hearing are in many ways similar to ours, they’re also very different. I started this project with only a passing interest in birds, and only gradually became interested in various little things they seemed to do differently- and sometimes better- than we do. But over time I’ve learned that they do all kinds of things differently than we do, having evolved different solutions to so many of the same problems our own ancestors faced. Birds are like the “What if?” version of us, how we might have turned out in a parallel or alternate universe. Except that they did turn out that way, and they’re right here and now, all around us, outside every day. Birds are way cool.

Note about sources: Evolutionary info on the middle ears of amniotes came from Cochlear mechanisms from a phylogenetic viewpoint*, Geoffrey A. Manley, Your Inner Fish, Neil Shubin, the absolutely awesome blog Evolution of Hearing and the TalkOrigins Archive’s 29+ Evidences for Macroevolution. Info on bird, reptile and other ears came from Winged Wisdom/Pet Bird Magazine, the Earthlife Web website, Melissa Kaplan’s Herp Care Collection and Wikipedia.

*The “Middle Ear Evolution in Amniotes” Awesome Graphic in this post is a re-formatted (WTWWU-ized) version of Figure 1 of this paper.

Thursday, January 6, 2011

Suburban Apex Predator, and the F-117 Barn Owl

Note: I had a hard-drive scare yesterday* and, for a couple hours, thought I’d lost the >90% complete draft of this post. I was totally, totally bummed. So I went over to Co-worker Matt’s office to commiserate, and ended up “telling” him the post. After I told him, Matt- who knew pretty much nothing about Owls beforehand- seemed genuinely into my “story-post” and impressed and interested by owls**. And then I realized that I didn’t feel so bad anymore, because at least 1 person had “read” and enjoyed the post. Just then the IT guy came over to Matt’s office looking for me; they’d recovered my drive.

*Yeah, that’s right- I blog on my work laptop. Oh, don’t get all sanctimonious on me; you’re probably reading this post on yours.

**Or maybe he was just yanking my chain to try and make me feel better. Whatever.

The Post

We moved into our current home in the Spring of 2002. When you move into a new neighborhood, you tend to notice all the little things- people out walking, how people maintain their yards, which houses have dogs that bark at you when you walk/run past, etc. One of the first things I noticed in our neighborhood that Spring was all the rabbits.

Our old neighborhood didn’t have rabbits, or if it did, I never noticed them. But here they seemed to be everywhere, and out not just in the early morning, but oftentimes right in the middle of the day. Awesome Wife and I joked that it was because now that we’d moved “uptown”, the neighbors didn’t let their dogs run free., and that if just one dog got out of its yard and roamed free for a weekend, the rabbits would probably disappear.

A few years passed. In early summer of 2005 a neighbor’s kid caught sight of a large owl perched on high up in a tall Blue Spruce next door. We spotted it almost every day for a couple of weeks. Sometimes it would hoot, and once or twice it spread its massive wings and flew off while we watched, probably annoyed by the neighborhood kids hanging out and chattering under its perch. After a couple of weeks it disappeared altogether, and we didn’t see it again. I wondered if all of our attention scared it away.

A few months later, in early Fall 2005, I was pedaling my bike home from a ride. I rolled down the little hill where I regularly used to spot rabbits out on a lawn and realized I hadn’t spotted a single rabbit in the neighborhood in, well, months. In fact I hadn’t seen one, since… that owl showed up.

I didn’t see rabbits again in our neighborhood until this past Spring. Over the Summer I’d see them out now and again, initially just around dawn, but later in the Summer out in the daytime as well. Rabbits aren’t particularly remarkable in a suburban neighborhood, but the kids like wildlife and would point them out to me, each other and their friends. Then last week, a neighbor’s kid* spotted this guy in the Elm** out front, the first one we’d seen in the ‘hood in over 5 years.

C1

*Different kid, different neighbor, but same house. We’ve seen four families in that house- loved the first, didn’t care for second or third, love the fourth. Sort of a cool full circle thing. AW and I are getting all kind of serene and Zen-like with respect to problematic neighbors. We don’t get upset; we just out-wait ‘em. Eventually they all move away or die.

**Which I blogged about in this post. I don’t mean just the species; I mean specifically this tree.

The Great-Horned Owl, Bubo virginianus, is super-easy to ID. If you’re in the Western hemisphere and you see a big owl with ear-tufts, it’s a Great-Horned (GH Owl). And chances are, if you live in a suburban or rural setting anywhere in North America, you’ve already seen one. Its range is huge, from Alaska to Argentina. In fact, everywhere I’ve blogged about in the Western hemisphere- Maine, California, Mexico, Costa Rica, even Brazil- I’ve been within its range. Like many animals with huge ranges, the GH Owl is a generalist, in this case a generalist hunter. GH Owls of course hunt rabbits and mice, but you might be surprised how many other things they eat. Snakes, lizards, squirrels, rats, shrews, bats, moles and other birds. OK, so they eat a lot of different things, so what? Tell me something I don’t know.

OK, here’s something you might-not-maybe didn’t know: If you live anywhere in suburban or rural North America, there’s a good chance that the GH Owl is the single most bad-ass, toughest, fearsome predator that routinely passes through your yard. Don’t believe me? Here we go.

Know what else they eat? Raccoons. That’s a pretty big meal for a C4predator that only weighs 3-4 lbs, but GH Owls routinely kill prey 2-3 times their mass. What’s that? You’re still not impressed? Get this: GH Owls are more or less the only predator that routinely hunts skunks. That’s not all- they regularly hunt armadillos and even porcupines!* Wait- there’s more! GH Owls regularly hunt other birds, and not just cute little songbirds, but big birds- like ducks, swans and seagulls. That’s not all- GH Owls regularly hunt other birds of prey, including Red-Tailed Hawks and Peregrine Falcons**.

*Sometimes they do so by grabbing the porcupine out of a tree and dropping it to its death. I know that bobcats kill porcupines (on the ground) by going for the face, but don’t know if owls do this as well. I should mention though that in researching this post I learned that hunting/devouring porcupines does not always end well for the GH Owl. I covered porcupines BTW in this post, and bobcats in this one, with (admittedly lame) additional video footage in this post.

**I haven’t done a proper post about Falcons, but covered their hunting prowess and tactics last year during Pigeon Week. Man, it is like I have a post for everything.

In fact, GH Owls regularly hunt other owls, including every other owl species in North America except the (larger) Snowy Owl. GH Owls typically hunt by perching still from a high vantage point, then swooping down onto their prey. Since their eyes don’t move within their sockets, having a neck that can rotate around up to 270 degrees serves them well. GH back captionBut GH Owls can also hunt in other ways, including standing in shallow water to hunt small fish. And GH Owls have a bad rap with chicken farmers, as they’ve been known to actually walk inside coops to kill chickens. Before leaving their roster of prey, it’s worth mentioning that GH Owls also successfully hunt domestic cats and even on occasion small dogs.

Tangent: You can’t help reading about B. virginianus’ range of prey without wondering what it would be like to be attacked by them. Do GH- or any owls- ever attack humans? The answer is yes, though I’m unaware of any doing so fatally*. GH- and other owls- will defend nests vigorously, and may attack visitors, researchers or others who molest them. Then there are the cases where the owls apparently attack people well away from their nests. On Vancouver Island there have been a number of attacks on runners and hikers by Barred Owls, Stix varia**. And a rogue GH Owl attacked several cross-country skiers last year in Bangor, Maine. It’s thought that these owls might be mistaking human head-hair for small mammal prey.

*I came across this claim, which sounds like a stretch.

**The Barred Owl BTW, seems to be a significant threat to the endangered Spotted Owl, whom it typically out-competes for habitat/nesting sites. Interestingly, it also hybridizes with the Spotted.

But would a GH- or any other owl- deliberately hunt a small child? There’s no record of it, and human toddlers exceed the 2-3x body-mass metric. But what about outside of North America?

The closely-related Eurasian Eagle-Owl, Bubo bubo looks a lot like a GH Owl, with ear-tufts and everything. But it’s bigger- up to 9 ½ pounds- and has been known to take deer fawns as big as 22 lbs*. Now we’re approaching toddler territory, though I’m unaware of any such hunting attacks.

*Wikipedia says up to 37 lbs(!), but every other source said up to 22…

But there used to be even bigger owls. Until around 10,000- and maybe as recently as 8,000- years ago, the Cuban Giant Owl, Ornimegalonyx sp., inhabited that island. Ornimegalonyx stood over 3 ½ feet tall and weighed over 20 pounds. Its wings were small, as was the keel of its sternum, suggesting it either flew only for short distances or not at all, and its legs were longer than a typical owl’s. Ornimegalonyx may have run after prey on the ground, or leapt from treetops. In any case, it was big enough to take a kid. Even though humans were in the New World 8,000 – 10,000 years ago, they don’t appear to have made it to Cuba until more like 5,000 – 6,000 years ago, meaning giant running owls likely never chased Taíno children through tropical jungles. But then again, the mandible of what was apparently a similarly gigantic late Pleistocene owl turned up some years ago in Georgia, so maybe…

The GH Owl’s primary weapon is its talons, which are kind of interesting in that they are semi-zygodactylous. Zygodactylous feet have 2 toes facing forward and 2 backward, in contrast to the standard passerine (perching bird) architecture of 3 forward, 1 backward*. (pic below, not mine)Aniso Talon captionIn GH Owls, the fourth toe is reversible, allowing it to shift between a 3 forward- 1 backward, or anisodactylous, to a 2 forward- 2 backward zygodactylous configuration (pic below, not mine**). The 3-1 config is used for perching, but the 2-2, which provides a greater coverage area, for hunting.

*We covered zygodactylous feet last year when we looked at Roadrunners. Seriously, everything.

**Captain Obvious, here…

Zygo Talon caption For most prey, the moment of contact is the moment of death- they never know what hit them. The talons of B. virginianus are incredibly powerful, able to crush bones with a gripping force of up to 500 pound per square inch. For comparison, a human grip generates a maximum force of some 80 psi, the bite of a German Shepherd roughly 250 psi, that of a Rottweiler 325 psi, and a human bite around 150 psi.*

*This is why you can open twist bottle caps with your teeth more easily than you can with your hand. Not that you should ever do so.

Side Note: These figures were surprisingly difficult to obtain* and make sense of, so take them with a grain of salt. Psi is not the same as bite-force; a Rottweiler’s bite has more force than a GH Owl’s grip, but the surface area of the latter’s talons is tiny in comparison. The important point is that, for something that looks rather thin and inconsequential, the talons of a GH Owl are incredibly powerful.

*Which is fair enough, when you think about it. Wouldn’t you hate to be the grad student tasked with getting the wolf or pit bull riled up enough to bite whatever measuring instrument they use with maximum force?

Back to bite-force, wolves and coyotes have much stronger bites than comparatively-sized domestic dogs*, with the exception of special breeds such as a Pit Bull, whose bite is phenomenally powerful. The bites of hyenas, lions and tigers are stronger still, in another category of force altogether.

*So I’m really glad that coyote in Emigration did not manage to connect with my right cheek.

Owls also have exceptional vision. Owl Eye captionTheir eyes (pic left, not mine) are as big as ours*, but many times more powerful- even in full daylight. Most owls can sight a mouse in the grass about 5 times further away than we could make out any object of that size, and in darker conditions the difference is even more dramatic. The eyes of owls are ringed by specialized feathers that reflect/direct light into the pupil, and their retinas are packed with light-sensitive rod cells, enabling them to fly and hunt in what looks to us like near-total darkness.

*Which is proportionally like our having baseball-sized eyes.

But perhaps even more impressive than an owl’s sight is its hearing, which is highly sensitive, particularly in frequencies around that of rustling grass. An owl’s ears are asymmetric; the GH Owl’s right ear is set slightly higher up on its head, and positioned at a slightly different angle. This makes an owl’s hearing more sensitive to position and direction of sounds than ours. Barn Owls in fact can hunt effectively in absolute darkness by sound alone, flying around and landing on prey with accuracies of a fraction of an inch. (I don’t believe GH Owls can quite do this.)

Side Note: BTW, the GH Owls “ear tufts” are nothing of the sort. Though ear_gho they look like the part of the outer ear that is technically the pinna (the outer, visible part) on a person, dog or cat, birds have no pinnas* (pic right = actual GH Owl ear, not mine). The avian ear does have specialized feathers, called auricular feathers, that serve to direct sound into the ear canal, but GH ear tufts aren’t those either. They’re display feathers, and have nothing at all to do with hearing. We’ll get more into avian ears in the next post.

*Pinnae? Pinnum? I’m never really sure.

Tangent: Let’s pause here for a second. Hopefully by now you’re convinced that the GH Owl- along with many other owls- is a totally Way Badass Predator. It’s for sure more bad-ass than hawks, and maybe even eagles. I didn’t appreciate how bad-ass until researching this post. Oh, I knew they were effective hunters and such, but…porcupines? Armadillos? Cats? And I guess I was surprised because they just don’t look that mean, but rather kind of wise and serene, and well “nice.”* Like, say you were an animal and you lived in a Watership Down**-type universe, where all the animals could talk to each other and you were lost and had to ask another animal for directions. Wouldn’t you be inclined to ask the wise old owl? But no- don’t do it! Because even though he looks so benevolent, he’s really like this hyper-effective, terminator-esque Silent Killing Machine!

woodsy-1 *And then there’s “Owl” of the Winnie the Pooh*** gang, and the USFS’s “Woodsy (“Give a hoot, don’t pollute!”) Owl, and even the wise old cheater-Owl (“How many licks does it take…?”) on the old Tootsie-Pop commercials. All of these guys come off as slightly-addled, geriatric, harmless softies. Couldn’t we have just one seriously bad-ass owl in popular culture?

**I love that book.

***Still think that bear should have pants.

I’m not the only guy suckered by the owl’s serene face: think about birds of prey in our culture. chicago-blackhawks-2009-stanley-cup-playoffs-western-conference-finals The Bald Eagle is our national symbol; it’s on the presidential seal and the quarter, and eagles grace the seals and flags of numerous other countries. We have sports teams named after eagles and hawks. Our military flies the F-15 Eagle and the Blackhawk Helicopter. Know what the much-vaunted F-117 “Stealth Fighter” is officially named? The “Nighthawk”. A Nighthawk- which I’ll mention just below in a moment, and is not at all closely-related to actual hawks- is a cool little bird, but it’s not even really a nocturnal hunter, so much as it is crepuscular, meaning active f_117_nighthawk_2around dusk/dawn. And you know what it hunts? Bugs. And it’s a little, inconsequential thing; hell, I’ve nearly run over them multiple times night-riding. Our nation’s baddest-ass techno-night-fighter-jet shouldn’t be named after a little birdie that flits around eating bugs. No, it should be the F-117 “Barn Owl”, because the Barn Owl is truly a bad-ass nocturnal predator.

But there’s no fighter-jet, no attack helicopter, no presidential seal, no flag, no heat-seeking missile either named after or with an owl on it. That’s BS. A few years from now, when I found the state of Wasatch*, the GH Owl will be our state symbol.

Wasatch State *I’ll have to cover this one in another tangent in another post, but briefly, it’s for Salt Lake and Summit counties to secede from Utah (West Virginia-style) and form a new state. Economically it’s a total winner for the new state, and would improve everything from class sizes to social justice to open space protection. The constitutional issues involved are thorny, but not insurmountable. I tell you what, I am always cooking up something…

The “faces” of owls are vaguely disk-like in profile, making them almost instantly distinguishable from nearly all other birds. The disk-profile is also thought to direct and optimize sound reception. Speaking of other birds, what are owls related to?

Owls have been around for something like 60 million years, and became widespread during the Eocene. Today, the owls, order Stirigiformes, include 2 families: the True Owls, Stirigidae, which includes the GH Owl and oodles other interesting species, and the Barn Owls, Tytonidae. For a long time it was unclear where exactly owls fit in the family tree of birds*, but they appear to be most closely-related to the order Caprimulgiformes- the Nightjars, Nighthawks, Frogmouths and Oilbirds.

*One theory was that they were more closely-related to hawks. The owl-like face of the Northern Harrier, Circus cyaneus, seems now to be an example of convergent evolution- not close kinship.

Side Note: Nighthawks, specifically the Common Nighthawk, Chordeiles minor, is on my slightly-embarrassing lb39ist of things-I-researched-and-meant-to-blog-about-but-never-got-around-to-doing-so. (Pic right, not mine*). They’re cool little birds which fly around close to the ground at dawn and dusk hunting insects, and are common in the foothills and high rangelands bordering the Wasatch. On several night-rides this Fall I came upon them suddenly, just sitting in the middle of the trail shortly after dark. As I rolled toward them they’d alight, and then fly in my bar-light-beam, staying just 10 or so feet ahead of me for a few seconds as I followed them down the trail. My plan was to get this on helmet-cam for a post, but I was never able to work out a light/cam configuration that captured the action.

*BTW, this is exactly how they look when you come across them in the evening just sitting in the middle of the trail- squat and squint-eyed, almost kind of smug-looking…

I’ve never been able to get decent night-time helmet-cam video. I’ve tried all different light/cam bar/helmet combinations, but the results are always the same- a small circle of white light in a field of blackness:

Believe it or not, that clip was made with both bar and helmet lights going full-blast- I could see fine. Around the same time I experimented with a bar-mount for the cam. Noise was always a problem, as you can hear in this clip:

I was able to partially damp the rattle with multiple rubber-bands, but it was still there. The lower-level video looked faster and better captured the lean-angle of the bike, which was cool, but I found the video quality sort of frenetic and annoying, and switched back to helmet-mount.

Their next closest relatives are the Turacos, order Musophagiae, a funky-looking group of semi-zygodactylous-footed, fruit and bug-eating African birds, and after them, our old friends, Swifts and Hummingbirds.

Owl Phylogeny I mention this not only because I’m always interested in what’s related to what, but also because this roster of the owl’s closest cousins rings a couple of bells from previous posts. Oilbirds and Swifts (specifically some Asian swiftlets) are the only 2 birds known to have accomplished another awesome hearing-feat: echolocation*. Isn’t that interesting.

*Which we looked at last summer in bats. It’s like… Oh yeah, I said that already.

We’ve looked at lots of differences between birds and mammals in how they’ve tackled the same problems, including vision, song, respiration, sex determination, “nursing” and thermoregulation. It’s time to check out their ears.

Next Up: The awesome saga of the middle ear.

Note About Sources: My standard sources for every bird-related post include Kaufman Field Guide to Birds of North America and the Cornell University lab of Ornithology All About Birds website. Additional info came from Phylogeny and Classification of Birds: a Study in Molecular Evolution, Charles G. Sibley & Jon E. Ahlquist, The Origin and Evolution of Birds, Alan Feduccia, Tracking & the Art of Seeing: How to Read Animal Tracks and Sign, Paul Rezendes, the Owl Pages website, the Exploring Nature Educational Resource website, the Colorado Division of Wildlife website, ChaCha (don’t ask), negah28.info, BirdsnWays.com, CubaHeritage.org and Wikipedia. Several of the photos in this post were provided courtesy of Hunky Neighbor.

Thursday, December 30, 2010

2010 Helmet-Cam Retrospective

Let me start by saying that, in general, I think it’s kind of pretentious to do a retrospective-year-in-review-type post, because doing so implies that a) the blog is more important/has a bigger audience than it actually does, b) the year was somehow exceptional or notable, which it really wasn’t (with the obvious though admittedly not-world-shattering exception that it was the first year I had a helmet-cam), c) even if it was an exceptional year, that I would somehow be in any way more qualified than any other Average Joe to, er, retrospect it, d) that the visual content of this blog somehow merits review/re-posting, and e) I think they always come off as a wee pit pretentious.

But, I’m doing it anyway, because a) I’ve been looking at a bunch of old helmet-cam clips this past week, which have really highlighted the remarkable changes in the living world over the course of the year, b) it allows me to get a post up during this quasi-nether-week without doing any real* research, and c) I guess, if we’re completely honest, I am just a wee bit pretentious.

*Just to be clear- the issue here is that I am lazy- not that I am unimaginative, or in any way out of cool post ideas. In fact I have a great two-fer brewing for next week, about a cool predator and hearing.

I get this weird thing about seasons every year. In the Summer I’ll be walking around in shorts and a T-shirt, maybe hiking or biking past some spot in the woods up in the mountains, and I’ll think that in just a few months, the forest all around me will be leafless, freezing cold, and under several feet of snow. And while I know it consciously, I just can’t really believe it. It just doesn’t seem intuitively possible that the same place could be so different in such a short time. Then 6 months later, skiing or what-not in the backcountry, I’ll have the exact opposite experience, looking around at the frozen silent forest, trying to imagine it green and leafy and warm and full of flowers and hummingbirds and dragonflies, and I just can’t really believe that it’ll be that different so soon. That all this snow will somehow melt away and the dead forest will just come back to life.

Tangent: I’ve been fascinated by the place-change effect of seasons for a long time, since long before starting this project, or even knew anything about forests. In the summer of 2001 I decided to photograph the same spot on the same trail weekly throughout the Summer/Fall. I didn’t see it through, but still have some of the old photos, reposted below.

Johns Slide

During past winters I’ve sometimes reality-checked myself by looking through photos from the preceding summer, which helps, but a still photo is just that- a still. But this year, looking at old video-clips, I’ve found a connection to the past cycle of seasons I never managed to experience before.

So anyway, I started to do a kind of a month-by-month helmet-cam retrospective, intending to document the change of seasons and be all kind of artsy and such, but by the time I got to May, I thought, “Man, this is a lot of singletrack through leafless scrub-oak footage…” So instead, I’m just going post a bunch of my favorite helmet-cam clips from 2010. Here we go:

The Clips, Already

Some of the best early season clips I got were down South. This is a portion of the descent of Upper JEM outside of Hurricane, UT, traversing the upper 3 members* of the Moenkopi formation. The trail is lined mainly with Blackbrush and the occasional Utah Juniper up top, with Rabbitbrush and Mormon Tea joining in lower on down. I love the flow of this clip, the way the land changes color as we tranisition between geologic members, the weird light and ominous clouds. Pine Valley Range in the distance.

*Upper Red, Shnabkaib, Middle Red

Tangent: Yes, that’s right. The helmet-cam was my Christmas present last year. What’s that? What did I get this year? Well, I received several nice gifts, eyeclops but one of the most interesting was a pair of Eyeclops Nightvision Infrared Binoculars. They’re not real night vision binoculars, like the kind of light-amplifying devices used by the military and such, but rather an infrared flashlight attached to a camera-viewer. It’s a fun little toy and I hope to use it for things like night-time bug-hunting, maybe checking out scorpions and such down in the desert come spring.

But in playing around with it (pic below, left = living room chair viewed in darkness) , I discovered a curious and unexpected side effect,Chair in IR which is this: it appears that artificial hair coloring doesn’t show up in infrared light. [I actually have a great photo that displays the effect, but unfortunately I can’t post the photo here, for reasons I can’t really get into.*] Meaning that when you look at someone with colored hair through the infrared viewer, their hair looks gray or white. You can actually pick up the viewer, scan a room full of people, and instantly see who’s dying their hair- Isn’t that freaky??

*Because Awesome Wife would likely leave me if I posted it. If you’re a real-world friend and want to see it, email me- it is way, way freaky.

Back in March I was in the same area with the team, and filmed this clip of the road descent into La Verkin with Teammate-Perry. I like this one for the rush of speed, as well as the physio-geographic significance: We’re crossing the Hurricane Fault here, dropping off the very, very Western edge of the Colorado Plateau and into the Basin and Range country, which extends clear to the Sierra Nevada.

Further down in the Mojave, this clip is from outside Blue Diamond, just outside of Las Vegas. The riding is slow and light dim, but I love the otherworldly feel of this ridge, following the faint singletrack, as well as the sense of solitude and open space just ~20 miles from the spawl and noise of the city. The tall yuccas alongside the trail are Spanish Dagger. Spring Range in the distance.

OK, this one isn’t helmet-cam, but I’m including it anyway. It’s driving across a wash in the Mojave, specifically Beaver Dam Wash, the lowest point in Utah. I love the blast of sun and green and water all together way out in the middle of this dry, spiky expanse of desert.

Tangent: What’s that? You’re wondering what else I got for Christmas. Well I got whole bunch of great books on my latest obsession, er, I mean interest- history of the first peoples in the Americas, and in the Great Basin in particular. (My recent rock art encounters have piqued my curiosity.) And I got some CDs and some more of that quick-drying underwear, and oh, yeah, this:

tallboy OK, so I bought myself that one…

Back up in Utah, this is one of one of my favorite stretches of Gooseberry Mesa, the South rim. Following Hunky Neighbor here, we’re rolling across the Shinarump Conglomerate, which marks the transition from Moenkopi to Chinle formations. About a minute in we roll up onto the next Chinle member “up”- the Lower Sandstone Member. We’re passing by Blackbrush, Mormon Tea, Cliffrose, Turbinella Oak, Utah Juniper and Singleleaf Piñon. Little Creek Mesa in the distance.

Closer to home, a couple of May bird-sightings. Here’s a male Black-Headed Grosbeak singing alongside the Shoreline Trail up above the Capitol…

And here’s a soaring Red-Tailed Hawk from Jack’s Peak. Oquirrh Range, Great Salt Lake, Antelope Island and Salt Lake Salient* in the distance.

*No, I haven’t explained this yet- it’s the geologic formation that comprises what I generally refer to as the “foothills” at the North end of Salt lake Valley. We’ll get to it when I do my Geology of the Wasatch post. (And yes, I will do a Geology of the Wasatch post one day and it will be awesome- my veritable Wasatch Opus. You will not want to miss it.)

Around the 1st week of June the forests around 7,000 – 8,000 feet practically explode in greenery. Here’s a clip from up in Pinebrook. The leaves (mainly Maple & Aspen) are only partway out, still that light, lime green color, and the underbrush (mainly Ninebark & Snowberry) though green, is still low, only recently freed from the weight of the snowpack.

Just 2 weeks later, on the eve of the solstice, I took this clip from the Northern (and best) stretch of the Mid-Mountain trail, passing through several Aspen groves. You can’t see it in the clip, but the trail is lined with blooming Sticky Geranium and Wild Rose.

I did some cool summer road trips this year. This clip is from along the North Rim of the Grand Canyon, riding the Rainbow Rim Trail. The tall conifers are Ponderosa pines. In stretches we pass through stands of Gambel Oak and New Mexican Locust. Out at the point we roll by a couple of Colorado Piñons, and finish off with a corridor of blooming Cliffrose. This section smelled fantastic. (At 2:27 I glance into the inner gorge.)

This clip turned out cool. It’s the full moon rising over the Paunsaugunt as I pedaled the bike path back to camp. There are all kinds of cool conifers on the Paunsaugunt. It’s hard to tell in the dark, but I’m pretty sure we’re passing through Douglas Fir and Ponderosa.

OK, another non helmet-cam clip, but a good view of Redfish Lake up in the Stanley Basin of Idaho.

Earlier that same day, here’s a clip from up on the ridge on the West side of the lake (so on the right side of the previous clip) with some nice views of the lake. The trees on this stretch are Douglas Fir, and geologically I suspect I’m rolling over a glacial moraine, not from the last glacial advance, but from the one before, likely ~100,000 years ago.

Later on that vacation, here’s a clip from our campsite on the Lochsa River up in Northern Idaho.

Tangent: I just realized that reading the 2 previous tangents, you probably think that the only thing I care about around Christmas is getting presents. I assure you, nothing could be further from the truth. For while I certainly enjoy receiving gifts, I certainly know what really makes Christmas a truly unique, special and magical time, which of course is Making Fun of People’s Holiday Cards. Oh come on, you know you do it too. Every family has a Crazy Aunt or some such who sends out a whacky form letter every year that you and your significant other just can’t wait to get.* Actually, in all seriousness, I like Christmas card-form-letters**. Yes, sometimes they have a lot of detail, but they’re a great way to get caught up on the lives of friends and family you don’t get to see very often.

*Sadly, my own Crazy Aunt stopped sending us her card/letter a few years ago. I can’t figure out if she stopped doing it altogether, or somehow got wind of me making fun of it and took me off the list. It’s a shame, I loved it. It was always written in this super-happy upbeat tone, but kept mentioning things that seemed borderline inappropriate for a Christmas card. Actual line from a past edition: “After breaking off his engagement, Tad*** bought a VW Rabbit and moved to California…”

**Except for the downer ones. You know, the ones that go, “It’s been a year of challenges for the Hetzweigs; Hal lost his job in May, Betty’s back in rehab, and we had to put down Rasputin this year, but we’re hopeful little Petey will learn to cope with his deep anger issues…” Gee, I’m sorry it’s been rough, but did you have to dump all this on us the week before Christmas? Couldn’t you have emailed me or something back in October?

***Not his real name.

The truth is, there’s only one type of holiday card that drives me batty, and that is the Card With New, Unidentified, Unannounced and Unexplained Family Members. I’m not talking babies or pets here- I’m talking adults. Several years ago one of my cousins sent us all a card with a picture of him, his wife, their 2 teenage sons, and… another teenaged boy. We don’t see this cousin but every few years, but so far as we knew, he’d always had 2 kids. Could we have somehow missed one over the years? We doubted it. The card had no explanation, and we chat so infrequently with him, his parents or his siblings that there wasn’t a smooth way to just call him up on some other pretext and say, “Oh, BTW, who’s the other teenager on your Christmas card?” And because we felt awkward asking, by the time the next year’s card came around (again, with mystery teen) it was too late to ask, and so… anyway it was like 2 or 3 years before we were clued in*.

*He was a teen from a troubled home who played basketball with their sons and whom they took in and became his legal guardians. A totally awesome, inspiring story. I just wish they’d noted it in the card so we weren’t scratching our heads (and then semi-faking like we already knew) for so long…

This year, we got a card from AW’s cousin, a single(?) man with a young son. The card said, “Happy Holidays from the Jones* Family” and had a photo of the cousin, his son, a middle-aged woman and 3 teenaged girls. Who are these people? No note, no names, no nothing**. None of these women were in his card last year. We hadn’t heard of a wedding or even a serious girlfriend and suddenly we get the Brady Bunch Christmas card… We are totally clueless…

*Not his real name.

**Which is ironic, because this is the kind of Christmas card that totally merits a lengthy detailed form-letter…

Closer to home, the Wasatch Crest always makes for good video. This clip is from SkiBikeJunkie, Coryalis and my 83-mile Fourth of July Super-Crest tour. You can tell by the low brush/grasses and the light Aspen leaves that it’s still early in the summer. In addition to the usual Wasatch characters, we pass a number of Limber Pines between around 1:00 and 1:20.

For comparison, here’s a piece of that same stretch, exactly 2 months later. Check out how much higher (and drier) the grasses are, and how the Aspen leaves are now a dark, mature green.

This next clip I like- even with the problematic lighting- because it’s one of my favorite stretches of Great Western Trail, and also because it’s my only helmet-cam clip of, er, me. SBJ was kind enough to film it later during the Super-Crest ride. The conifers in the shady sections here are mostly Engelmann Spruce, which do real well on these North-facing slopes*

*And have been doing even better following a century+ of fire suppression in the Wasatch.

Here’s part of that same stretch 3 months later, the trail now lined with fallen Aspen leaves. Passing through the darker Spruce stands, the golden underbrush seems almost to glow, lighting up the forest from below.

The colors peaked in mid-October. Here’s another stretch of Mid-Mountain, about 2 miles North, and 4 months after, the Solstice-Eve clip up above.

Later in the Fall we returned to Gooseberry, where I took this clip following Fast Jimmy through Piñon-Juniper along the rim, with glimpses of the banded Moenkopi formations below.

In mid-November I followed Cory on this high-speed descent down into City Creek. The oaks and maples are bare, the grasses wilted and brown, the sky gray. The landscape is practically begging for snow. We’re rolling over conglomerate soils here, eroded down from the tertiary conglomerate cliffs above. I’ve been trying to keep up with Cory on the downhills for 15 years now, and he just seems to be getting faster. We hit 29.9mph on this stretch.

I saved my favorite clip for last. It may seem like an odd pick, and my feelings aren’t hurt if you don’t like or get it. It’s slow and meandering, I’m alone, the scenery is unspectacular, and the trail rather undefined. It’s the descent of a side trail* off Mid-Mountain trail during the peak bloom of Serviceberry on the day before the summer solstice. The video’s slow and poky, but when I watch it I feel the sun on my neck and smell the brush all around. I feel the Serviceberry brushing my arms, the Sagebrush scratching my shins, my flexed stomach flat on the seat and the braking-burn in my forearms**. For me, this clip is Summer.

*Lower Finesse.

**Because yes, I am a Luddite and ride with v-brakes. Or rather rode. Did I mention my new bike?

It was a good year. The next one will be great.