Bug Rescue Part 2: Dragonflies are Way Cool

After my ride I showered, dressed and drove into the office. At about noontime I walked out the back door of our building, by the overhang and the bench where the smokers hang out, to run some errands. On the walkway about 10 feet from the door was this dragonfly, just sitting there. It was cool out, but not cold, so I wasn’t clear why it was sitting there. I picked it up while it flapped feebly (Dragonflies really can’t walk, as we’ll see in a moment) and placed it on the grass, thinking at least to get it out of the way of foot traffic. I sprinted back up the back stairs for my camera, returned to find her still in place, and snapped these photos.

Tangent: Right by the back door of my office building is, as I mentioned, a little overhang with a bench where smokers hang out. Two of my coworkers- let’s call them “Aaron” and “Jimmy”*- are smokers, and I’ll frequently stop to say hi to one or the other on my way in or out of the building. Sometimes they’ll be chatting with other smokers, and other times just taking a break alone, quietly looking out across the creek, or toward the mountains in the background. And, I have to admit that deep down, I am a teeny bit envious. Smoking gives them an excuse to go outside, sit on a bench on a nice day and, for a few minutes, do nothing. Oh, I get that smokers also have to huddle outside on freezing days, but here in Utah it seems that there are, on the balance, more nice than bad days to pass a few minutes out-of-doors.

*Not to be confused with “Fast Jimmy”, who does not smoke, and is not a coworker.

Of course we non-smokers can also take mini-breaks, but since we don’t have an “excuse”, we’re more furtive about them, and spend them staring at our screens, pretending to work, while we read blogs or Dear Prudence* or whatever.

*I always thought I’d make a great advice columnist. How do I get that job?

Office smokers also tap into a little social network that we non-smokers are largely cut off from. There are probably a dozen other companies represented in our building; I don’t know a soul from any of them*. But Jimmy and Aaron are often chatting easily with smokers from several other companies, and so, oddly, smoking has expanded their world.

*Except that crazy older woman with the spiky red hair who always tries to start up a conversation with me in the elevator. Or did, anyway. Now I always take the stairs.

Nested Tangent: It’s probably expanded the world of Aaron- who is single- even more, as several of the smokers over the years have been attractive young women. For a while I teased Aaron about this, as I often came across him smoking/chatting with 2 particularly striking young women who worked at the multi-level-marketing company downstairs*, and whom I referred to- in what I always felt was a particularly inspired bit of double-entendre- as “the Smoking Hotties.”

*Special Footnote for Non-Utah Readers: Every office building in Utah contains a multi-level marketing company. The products touted are almost always health/wellness-related, which is kind of ironic in that most of the people who actually work at these companies, uh, don’t look all that healthy.

Yes, I know that Aaron and Jimmy will likely pay for their pleasant downtime-breaks and expanded social world by, well, you know, dying horrible premature deaths and what-not, but that’s not the point. The point is- and I do have one- why do you need an excuse to go hang outside for 5 minutes in the middle of the day? If I just went out and sat on the bench and a coworker passed and saw me doing nothing, they’d probably think it a bit odd. But if I were smoking, well then that would be totally fine…

The order Odonata, which includes both dragonflies and damselflies, includes some 5,500 species across all continents except Antarctica. The big obvious difference between dragon and damselflies BTW is the resting position of the wings. If it folds them back when at rest, it’s a damselfly; if it keeps them out at 90 degrees to the body, it’s a dragonfly.

Extra Detail #1: They also exhibit different mating flight patterns. Dragonflies generally mate while flying. Damselflies spend more of their mating time perched, but often fly- while connected- for short distances from perch to perch.

Tangent: Every once in a while, you’ll see or hear about an animal doing something that looks really fun- jumping out of the water, swinging between tree limbs, flying rapidly through the air. I just want to point out that mating while flying sounds like about the funnest thing imaginable.

Extra Detail #2: Odonata appears to be monophyletic, meaning the group includes all of the descendants form a common ancestor. Dragonflies (infraorder Anisoptera) also appear to monophyletic. But damselflies (Infraorder Zygoptera) appear to be paraphyletic, in that one big genus (Lestes) turns out to be more closely-related to dragonflies than to any other damselflies.

This sounds kind of geeky, but it means that “Damselfly-ness”, specifically the hinged-wing mechanism, has to have evolved at least twice among the odonates, a cool example of convergent evolution.

*I explained monophyly and paraphyly in this post.

The dragonfly I rescued is one of the most common species in North America, and if you’ve ever paid attention to Dragonflies you’ve almost certainly noticed it. It’s the Common Green Darner, Anax Junius, and its distinctive green color is a quick identifier, as is the apparent “bulls-eye” atop it’s forehead/“nose” when viewed from above.

This one was most likely female, because the main part of the eyes are brown-hued. The long abdomen, consisting of 10 segments, is brown or dull/dark purplish in females, but often a bright blue in males. While we’re on the topic of gender, this is probably a good time to talk about the lifecycle of Dragonflies.

If you know anything about dragonflies, you probably have heard that they develop through an aquatic “nymph” stage (pic right, not mine) before emerging from the water and developing fully into flying adults. I’ve known this for a long time, and always thought of dragonflies, and other insects with an aquatic nymph stage, as sort of “amphibious bugs”; they spend a little time in a “child” stage in a pond, before getting on with, you know, their “real” life. But when I started learning about them, what really surprised me about dragonflies was how much of their lives- the vast majority in fact- is spent in the nymph stage. Green Darners commonly live as nymphs for up to 2 years, and other species live as nymphs for as long as 5 or 6 years.

But an adult darner lives only for a couple of months. Think about how weird this is. We think of animals developing like mammals and birds and reptiles generally do- we’re born, we grow up quickly, and spend the majority of our lives in sexually mature adult form. But what if you were born, grew to about the size of an 8 or 9 year old, and then stayed that way for like 60 years? Then, right around when you collected your first social security check, you suddenly hit puberty, grew armpit hair and got interested in the opposite sex. But you had to hustle, because you only had a few years or so to marry and have kids before you dropped dead! That’s pretty much what the lifecycle of dragonflies (and many other insects) is like…

A dragonfly’s life, therefore, is mainly a nymph’s life, which most of us never see. Dragonfly nymphs are fearsome aquatic predators. How fearsome? Did you ever see any of the Alien Movies?*

*I love the original Alien. The various sequels never worked for me. But I loved the original. I’ve seen it like 10 times, and every time where it gets to the part where Sigourney Weaver goes back for that cat, I’m always yelling at the TV, “Screw the cat! Just get out of there!”

The super-scary alien-predator in the Alien movies had several fearsome weapons- spiked tail, long claws, acid blood, etc. But the most terrifying was its extendable jaw. Remember that? It would get real close to you, open its wide jaws menacingly, all fangs and drool, and then all of sudden, another set of jaws would jump out from inside its mouth and like rip your head off! Wasn’t that scary? Well that, more or less, is exactly the deal with a dragonfly nymph!

The extending jaw of a dragonfly nymph isn’t positioned like the Alien jaws (i.e. it’s not inside the mouth) but rather the lower jaw, the labium (diagram left, not mine, and below, not mine either) is hinged and extendable. As the nymph closes on its prey, the labium jets out lightning fast, clamps down on the prey, and yanks it backward into its maw. I’d think that if you’re a mosquito larva or a small tadpole, it’s about the scariest thing imaginable.

Nymphs molt between 6 and 15 times before climbing up the stem of an emergent plant* above the surface of the water, where they molt a final time, emerging at last as a winged adult. This final molt, BTW, which is followed by a wing-drying period, is one of the most vulnerable times of a dragonfly’s life. Although they’re fearsome hunters, they’re also regularly preyed upon by everything from birds to frogs.

*I explained emergent plants in this post. Man, it is like I have a post for everything.

As aerial predators, dragonflies feed upon all sorts of mosquitoes, midges, gnats, flies and other insects. Their 6 spiked legs, held in a basket-like formation as they fly, are used to scoop up prey toward the mouth.

In fact, scooping and perching are more or less the only things a dragonfly can do with its legs; they can’t really walk, and so if unable to fly are pretty much immobilized.

Male Green Darners, like most male dragonflies, are territorial, and patrol their territory getting into tussles with interlopers, and looking for females. The male produces a sperm packet from the tip/10^th segment of his abdomen, and then curls his abdomen under itself to deposit the packet in a small depression on the underside of his 2^nd abdominal segment.

He then flies out and grabs the head of a female in mid-air, with the clasping genital tip of his 10^th segment. Then, connected tip-to-head, the two fly around together for a while, in the dragonfly version of foreplay. Usually the male does the flying and just pulls the female along for the ride, but every once in a while the female might flap a for a bit while the male rests.

After some period of time, the female bends her abdomen below her and up under the male’s abdomen to pick up the sperm packet with her genital opening. They fly around in this “wheel” position together for up to 15 minutes.

After copulation, different species do different things. A female Twelve-Spotted Skimmer, for example, promptly disengages from the male and speeds off on her own to lay eggs on the surface of a nearby body of water. But Green Darners remain connected and fly to the water’s surface together, repeatedly, to lay eggs in multiple locations.

Extra Detail: Dragonflies use the same XX/X0 chromosomal system of sex determination used by Fruit Flies, which I described in last year’s Housefly series*. I had a hell of a time BTW determining the chromosome # of A. junius. I believe the diploid # is 27 (male)/28 (female) but this could be wrong.

*Man, was that an awesome series or what?

Damselflies, BTW, remain connected for egg-laying, but take it a step further. The pair lands on an emergent plant stem, then crawls down together- still connected- beneath the water’s surface where the female deposits the eggs into the stem of the plant. It’s suspected that the pair may do this together because the female requires the added strength/mass of the male to break the surface tension of the water and re-emerge into the air.

One of the reasons dragonflies fascinate me is that, like sharks or scorpions, it’s a really old design that’s held up amazingly well. Think about it. Tool-using hominids have been floundering along for maybe a couple of million years and already are in the midst of a wacky population explosion/environment-world-alteration that’s anybody’s bet as to whether they’ll survive it. Dragonflies have been around for at least 325 million years, and were not only one of the first types of insects to evolve flight, but were part of the teeny fraction of living creatures to survive the Permian extinction. And here they are today, thriving all over the world, with largely the same structure and hardware.

One great example is the eye, which I won’t cover in detail here, because we covered it in the run-down of compound eye types I posted about in the Housefly series. You can check out that post for details, but the key take-away is that the eye of the Dragonfly, an apposition compound eye, is the simplest and most ancient compound eye “design” there is. Compared to the eye of a housefly, moth or lobster, it’s downright primitive. Yet dragonflies are stunningly successful visual hunters.

Another example, one that also contrasts with the housefly, is wings. The wings of a housefly are highly-advanced, with the 2 rear ones having evolved into sophisticated tiny flight stabilizers called halteres. A dragonfly by contrast is equipped with the same primitive 4-independent-wing system common to the earliest flying insects.

Side Note: I should mention that the whole topic of the evolution of wings and flight in insects is one of the big stumpers in evolution. There are lots of ideas, but still no consensus. With something like a bird or a bat or a pterosaur, even if we can’t figure out exactly how it evolved flight, it’s pretty obvious where the wings came from- the forelimbs. But there’s not an equally obvious wing-precursor-limb in insects. One thing that does seem apparent is that insects don’t seem to have been particularly successful or abundant before evolving flight…

Yet dragonflies are awesome fliers. They’re fast and maneuverable, rapidly changing direction and accelerating on a dime to speeds of >60MPH. They can also fly backwards (though at only around 3% their maximum forward speed), and hover in place for up to a minute.

Extra Detail: Know why they can’t hover longer? Because they overheat, which makes perfect sense when you think about it. Dragonflies do most of their flying at significant speeds, experiencing fast, cooling airflow. In the absence of that airflow, they run hot. Plus, their tracheal respiratory system- to which we will return momentarily- is more efficient in strong airflow.

Dragonfly wings, though ancient in form, turn out to be remarkably sophisticated. They consist of largely clear membranes held in place by a network of veins. All dragonfly and damselfly wings have 5 primary veins. Some veins are darker and thicker than others, and these support portions of the wing that experience greater stress during flight. The wing has a notch/vein-junction on the forward edge called the nodus, that is critical to the strength and structural stability of the wing.

The wing does not form a smooth surface; if you run your fingertips across the surface of the wing*, it feels corrugated. But these corrugations aren’t random; their pattern optimizes airflow in a way that combines the advantages of a flat surface with an airfoil. Dragonfly wings cut through the air with minimal drag, making odonates some of the relatively few insects that are excellent gliders. Yet the wing, despite having no real curvature**, exhibits awesome lift properties. Human engineers haven’t developed anything like the dragonfly wing.

*Only do this with an already-dead dragonfly. Man-handling the wings of a live dragonfly will likely mean its early demise.

**I should say “consistent curvature”. It could be argued that the wings exhibit a type of cumulative effective curvature. See sources for more details.

Another cool feature of dragonfly wings is the teeny-weeny little opaque/colored patch on the front edge of the wing by the tip. I’d noticed these patches in the past and assumed they were simply decorative. But the patches, called pterostigmae, are highly functional. The pterostigma is a region of much denser cells that increases the mass of that portion of the wing and adds significant gliding stability. Gliding with a long, light wing is apparently more stressful than you might think, and the presence of these weighted patches is estimated to improve gliding efficiency by some 10-25%.

Side Note: While we’re on the topic of wings, it’s worth noting that these structures and characteristics of Dragonfly wings have been around for a very, very long time, even back in the Carboniferous period (300 – 360 MYA) (artsy conception right, not mine), when dragonflies grew far larger than they do today, with wingspans of up to 28 inches. That implies that these huge dragonflies were still incredibly agile fliers, which would’ve been awesome to see, though probably a bit un-nerving were one to buzz close by…

The presumed reason for large size was the greater concentration of oxygen in the atmosphere in the Carboniferous, likely over 30%*. The increased O2 levels would have made the tracheal respiratory system of insects** more efficient, allowing them to grow- and fly- at much larger mass.

*Which is higher than the concentration necessary for wet wood to burn, and makes you wonder about the forest fires in those times…

**Which I touched upon in this post.

What’s interesting about oxygen and bugs in the Carboniferous though is that although many other bugs grew much larger than they did today, not all of them did. Cockroaches for example, which also were around at that time, did not grow particularly large. In fact, I believe(?) that the largest cockroaches that have ever lived are around today. In recent experiments researchers have raised dragonflies*, roaches and other bugs under hyperoxic (high oxygen level) conditions, and found that while dragonflies, and most other insects, grew bigger and faster than they do at normal O2 levels, the roaches grew at roughly half the rate the do otherwise, and their tracheal tubes were abnormally small.

*Dragonflies are apparently a real bitch to raise in captivity. Feeding them is the problematic part…

So what was my lady dragonfly doing just laying around on the sidewalk? Maybe she was old and about to check out. Maybe she was out hunting and nightfall caught her out and about. Or maybe, just maybe, she’d spent the night in unfamiliar country, in the middle of a migration.

Out of thousands of dragonfly species, only a few dozen are known to be migratory. The Green Darner is one of those, but much about its migration behavior is still unknown. And in some respects, the more that becomes known, the more confusing the species and its behavior becomes.

In the Eastern and central US, Green Darners are known to form huge swarms, numbering up to over a million, migrating South in the Fall. Their paths and destinations are not completely known, but swarms have also been reported in Central America, suggesting crossings of the Gulf of Mexico. Such crossings, if they do occur, are certainly possible. Although the maximum fat-reserve slight time of a Green Darner is thought to be only about 8 ½ hours, migrating dragonflies often feed while on long-distance journey, taking sustenance from what is known as “aerial plankton”, including tiny aphids, midges and spiderlings aloft in the sky.

Extra Detail: The ~8 hour estimate comes from analysis of dragonfly body fat, which can account for up to 30% of body mass. Whoda thunk?

Dragonfly migration, like that of monarch butterflies, is multi-generational; the dragonflies who fly South in the Fall are not the same individuals who fly North in the Spring. Long-distance migration is always awesomely impressive, but multi-generational long-distance migration even more so. How on Earth do they do it? Does every dragonfly have a built in instinctive geographic map and awareness of the world? Do they crawl up out of the swamp, do a final molt, and think, “Oh hey, looks like I’m in Belize. Guess I better start flying to Ontario…”? That’s hard to swallow. Insect brains are teeny-weeny-tiny, and in dragonflies, something like 80% of that teeny brain is believed to be devoted to visual processing. It seems unlikely that they could possess anywhere near that level of geographic self-awareness,

To try and better understand dragonfly migration, researchers in the Fall of 2005 captured 14 Green Darners (1/2 male, ½ female), equipped them radio transmitters, and then monitored their positions for an average of 6 days each. What they found was that migratory flight appeared to follow simple, predictable rules. For example, the dragonflies migrated Southward roughly every 3 days. A Southward-flying day always occurred when the previous night was colder than the night before. Migration days tended to occur on days with lower windspeeds, and no dragonfly was observed migrating on any day where the winds gusted to over 16 mph. Winds were most often Northerly on migration days. Many of these behaviors are remarkably similar to migrating songbirds, who regularly mix up migrating and “stop-over” days over the course of their annual migrations.

In other words, the behavior suggested that a dragonfly brain follows simple, almost Boolean, rules in migration and navigation, which might explain how something so small-brained might accomplish such impressive long-distance navigation and migration.

Tangent: There’s a wonderful analogy here that I can’t resist. Remember the Life Reference Architecture tangent from the Triangle Man post? It’s like the Dragonfly brain contains a “Migration Decision Point”, a set of Boolean, context-driven rules, which guide its decisions in that part of its life. I wouldn’t be surprised if dragonfly behaviors in other areas- hunting, mating, predator-evasion- could be similarly encapsulated in Boolean format. Maybe the Reference Architecture is an effective analogy for how an insect brain works- a set of Decision Points that, in simple form, drive apparently complex context-based decisions.

Green Darners don’t always migrate in swarms (and to my knowledge swarms don’t occur in the Western US). Sometimes they migrate solo, though again, it’s not clear how far or where. But fascinatingly, many Green Darners don’t migrate. Instead they over-winter, and do so in really cold places all over the US and Southern Canada. They over-winter not as adults, but as nymphs, in sort of a diapause, or delayed developmental state, under the ice in frozen ponds, wetlands, etc.

So if Green Darners can over-winter in cold climes, why migrate? A decade ago dragonfly researcher Philip Corbet suggested that maybe the migrants and non-migrants represented 2 distinct subspecies of Green Darner. Such an explanation would make sense. Maybe the non-migrants were Darners who had figured out how to survive the Northern winters, and were on their way to forming a new species of dragonfly. But subsequent research seems to have debunked the subspecies hypothesis. DNA analysis of nearly 100 Green Darners, both migrants and non-migrants, collected across North America revealed several distinct genetic lineages.

Side Note: This kind of lineage-analysis has been done with lots of creatures, including humans. You’ve probably heard of the “Mitochondrial Eve”, the presumed most recent common female ancestor of all people alive today. Subsequent research has suggested all sorts of more recent maternal and paternal lineages all over the world. A fascinating example is described in Brian Sykes’ Seven Daughters of Eve*, which details research around the seven maternal lines from which the vast majority of Europeans appear to be descended within the last ~55,000 years or so.

*The concept and research of the book is fascinating. The fictional what-if chapters were a little less compelling for me.

What researchers found was that both migrants and non-migrants existed in multiple separate Green Darner lineages, meaning that non-migratory (and/or migratory) behaviors had apparently come about repeatedly and independently, suggesting a significant degree of “plasticity” in migratory tendencies across the species.

By now you’re probably getting an idea of why I characterized Green Darner migration as confusing. I don’t know where my lady dragonfly came from, or how she wound up on the walkway by the smoker’s hang-out. But I’m glad I stopped to check her out. Second bug rescued.

Note About Sources: I had awesome sources for this one. Thanks to friend and fellow nature-blogger KB for her help in accessing materials. General info on dragonflies came from National Wildlife Federation Field Guide to Insects and Spiders of North America, the Insects of West Virgina website, Suite101.com, and the Tree of Life web project. Info on dragonfly wings and aerodynamic properties came from Aerodynamic Characteristics of Dragonfly Wing Sections Compared with Technical Aerofoils, Antonia B. Kesel. Info on Green Darner migration swarms, behavior and genetics came from Simple rules guide dragonfly migration, Martin Wikelski et al, Massive Swarm Migrations of Dragonflies (Odonata) in Eastern North America, Robert Russell et al, Genetic diversity and widespread haplotypes in a migratory dragonfly, the common green darner Anax Junius, Joanna R. Freeland et al and Phylogeny of the Dragonfly and Damselfly Order Odonata as Inferred by Mitchondrial 12S Ribosomal RNA Sqeuences, Corrie Saux et al. Additional swarming info came from The Dragonfly Woman, the blog of entomologist Christine Goforth, which I recommend for anyone interested in dragonflies.

Bug Rescue Part 1: Black Widow Karma

Friday I rescued 3 bugs*. All were interesting, and I’m going to try to blog about all 3. The first one is easy, because I’ve blogged about it before. So I’ll just share a couple of quickie-pics, point you to the way cool details in the prior post(s), and then hopefully get a couple of real posts up on the other bugs later in the week.

*Actually, none of them was a true bug, which I explained in this post. Specifically, I rescued an arachnid, an odonate and an orthopteran.

Tangent: It occurs to me- as it probably has to you- that on the heels of a 5-part series covering the geology, flora, archeology, hydrology and (a bit of) fauna of- of all places- the Grand Canyon, posting about rescuing bugs may seem a bit tame, if not outright parochial, in comparison. To which I have a 2-part response:

First, as much as I’d like to spend every week hiking canyons, exploring cloud forests, biking deserts, searching for rare trees, running away from bears, making helmet-cam geology videos and camping with friends, I am, alas, unable to do so. So to watch the world wake up, I must do a fair amount of that watching a bit closer to home.

But second, many of the posts I’ve most enjoyed doing (and learned the most from) have been home-turf posts, blogging about everything from pigeons to magpies to houseflies to stargazing in the backyard to porcupines and dandelions. So get over it. I have- just while writing this tangent. Which BTW, is the real secret of the tangents in this project: they are wonderfully therapeutic.

Friday morning I was riding the Shoreline trail before work right around dawn. I’d climbed Dry Creek in the semi-darkness, switched off my light at the first valley overlook, and was cruising along the next flat stretch, when I spotted a big, dark spider just sitting in the middle of the trail. I stopped to check it out, and it was pretty obviously a Black Widow, Latrodectus Hesperus. I flipped it over with a twig and confirmed the red hourglass on the underside. It was alive and moving, but very sluggish, presumably from the cold. It was probably a female- big, black and shiny, with a round abdomen.

I posted about Black Widows 2 years ago when I found one hiding in a pile of bricks in my garage. In the first post, I highlighted their venom, which is about 15 times as potent as Rattlesnake venom, and, were it delivered in comparable quantity, would be routinely fatal to humans. The venom contains at least 7 different toxins, 5 of which work on invertebrates, 1 of which works on vertebrates (us) and the last of which appears targeted specifically for woodlice.*

*Which posted a bit more about in this post, and then finally did justice to in this post.

What was she doing in the middle of the trail? Males do go wandering about in search of females, but adult females generally park it in a web and stay put unless disturbed or threatened. Sitting out in the middle of the trail like that, with the usual hordes of trail runners and mtn bikers only an hour or so behind, she didn’t stand a chance; she’d be smushed like a Darkling in no time.

My second Black Widow post, which focused on lust, ended with the spider escaping in my garage and me worrying about how to root it out. About a week or so later I happened across her out in the open and promptly squashed her. I hadn’t seen a Black Widow since.

Tangent: As I hinted in the Darkling post, over the last year or so I’ve been going through sort a My-Name-Is-Earl thing with respect to bugs, and little critters in general*, trying to avoid squashing them and moving them out of harm’s way when possible. Part of this is likely driven by just being a nature-freak-bleeding-heart-enviro-softie, and part of it is probably connected to my evolving worldview and perspective regarding the nature of self. But I suspect the lion’s share of it has been driven by the Gandhi-like example of Twin B, who never squashes a bug, and goes out of her way to help out little critters in trouble.

*Including a bird, a bat and a toad down in Florida 2 weeks ago.

Using 2 twigs I gently lifted the Black Widow up off the trail and deposited her in the brush a foot or so downhill. First bug rescued.

Note About Sources: As longtime readers know, I do not own an electron microscope. The spinneret inset is from the Smithsonian National Museum of Natural History website.

Grand Canyon Part 5: The River

We moved our camp down to the next- and only real other- junction in Tuckup, that of the main canyon and the Northeast arm, pausing to down-scrabble and hand off packs several times. Shortly before arriving at the junction, we passed under a feature I’ve encountered spanning no other canyon on the Colorado Plateau: a conglomerate arch.

I explained conglomerate rocks last year closer to home, in City Creek Canyon. The hunk of conglomerate that the arch is carved out of is similar, though I’m sure it formed at a different time. But I don’t know when it formed. I suspect it was deposited in an existing channel in the Muav, but at a much later time than the Temple Butte formation we scrambled up in the last post. But I haven’t pinned it down in any of my geo sources*.

*My best guess is that it was deposited in the last million years. I know that there are deposits from basalt flows in Tuckup and its tributaries laid down between 700K and 1M years ago. The arch/bridge appears to be made of conglomerate, not breccia**, but I wonder if some of the eruption and flow events of that period could be related to the deposits that formed the conglomerate. Just a hunch.

**Which I explained in the same post.

In any case, it’s not technically an arch, but a natural bridge, in that water runs under it. Specifically it’s a waterfall natural bridge, a type that is created by subterranean stream piracy*, which is a fancy term for when the flow of a stream gets diverted underground into openings/crevices beneath. The flow eventually undercuts the surface, leaving a bridge supported by the former stream banks.

*Is that the coolest term ever or what?

The arch looks crumbly and fragile- like it’s going to fall on you any minute. Guidebook author George Steck claims that it’s stronger than sandstone, but The Natural Bridge and Arch Society* calls it a “relatively fragile structure.” In any case, we didn’t try jumping on it.

*Man, it is like there is a society for everything.

Our new camp was one of the coolest sites I’ve ever camped at, on ledges maybe 30 feet above the canyon bottom, with easy access to water, plenty of flat space for sleeping (pic left = my sleeping bag on ledge), cooking and lounging, and an overhang for rain protection (not that we needed it.) And the view from the “porch” was fantabulous, though our night sky was just a narrow band between the canyon walls. Ledge sites are nice also because you cook and sleep on rock, not sand, which means that everything- you included- feels clean, not gritty. If the site had any logistical downside, it was the necessary hike/scramble to access enough soil to dig a cat-hole*.

*To, you know, poop.

Side Note: While I’m on the topic, decent campsites in Tuckup Canyon are extremely limited. This is because the canyon is narrow pretty much the whole way from about a mile below Shaman’s Gallery on down to the river, which makes for great hiking, but tricky bedding. Really the 3 main camp-able spots are the junction with Cottonwood Canyon, the junction with the Northeast arm, and the beach on the river. Fortunately the Park Service limits the number of backpackers in the canyon via a permit system, but competition for sites is still possible.

We spent the afternoon exploring the Northeast arm, a fun scramble of ledges, chutes, pools and tunnels, before returning to camp, eating and crashing.

Side Note: Something else about camping. It was remarkable how much warmer the nights became as we progressed down-canyon. Thursday night up on the rim at ~5,800 feet there was frost when I awoke. At the Cottonwood Canyon junction (~2,700 feet) it got down into the low 50’s. At the Northeast arm junction (~2,100 feet) it didn’t get below 60F the whole night. Oddly, the days were still quite pleasant, never above ~75F.

The next morning we packed lunch, rope, a couple of carabiners and headed down-canyon. By this point there was water pretty much continually, and after a couple of miles we reached a deep pool with a little waterfall that looked difficult to climb back out of an the return. We backtracked a short way and found a faint bypass trail that soon climbed high up above the canyon bottom. The (very exposed) trail followed a sloping band of shale-y soil that I realized was the Bright Angel Formation, consisting of extremely fin-grained shale laid down some ~515 - 530 million years ago that always forms slopes, erodes easily, and sometimes has a faint green-ish tinge. The green color comes from Glauconite, which is a kind of mica that forms in sediments either as or after they transform to solid rock.

Side Note: We passed under a huge, exposed hanging garden here, probably fed by seeps occurring where the Muav limestone meets the Bright Angel shale.

Dropping back into the canyon bottom, we were on/in rock again, but now a different rock- the Tapeats Sandstone. Tapeats, laid down ~530 – 545 MYA is thought to have been formed in tidal flats, tidal channels and beach deposits in and by a Cambrian sea. It features frequent ripple marks and trilobite fossils. From a hiker’s perspective, it seems to erode into many, many horizontal ledges, forming open plazas separated by repeated staircases. In spots where it gets steeper, the ledginess provides ample finger and toeholds.

In and by the larger plaza-pools, we began to notice a number of toads, which on closer inspection, were decorated with bright red spots. These are Red-Spotted Toads, Bufo punctatus, and they are opportunistic breeders of the desert Southwest. Normally nocturnal, they became unusually active following rains, quickly mating and laying eggs in pools. The eggs hatch in about 3 days, and mature into toads in 6-8 weeks. The same rains that caused us such trouble on the drive in were the reason we were seeing so many of them now by day. They don’t “croak” like traditional toads, and we thought them curiously silent. But later I learned that their “croak” sounds more like the high-pitched “chirp” of a cricket, and that perhaps a few of the occasional “crickets” we heard in the evening were actually male Red-Spotteds seeking mates.

Bufo is a huge genus, with around 150 species occurring worldwide. As a rule they’re lousy jumpers (especially compared to frogs) and the Red-Spotted Toad tends to walk/shuffle more so than jump (they’re ridiculously easy to catch.) To compensate for their lame mobility, many Bufo species exude defensive, toxic skin secretions. Bufo boreas, for example, the common and widespread Western Toad (which you’ve undoubtedly seen if you live in the Western US and often hybridizes with B. punctatus) produces skin toxins that repel many predators. Other species produce skin poisons that can kill a large mammal that eats them, and some of these poisons, such as that secreted by B. alvarius, the Sonoran Desert Toad, are hallucinogenic (leading to the whole licking-toads-thing, which- like Datura- I recommend you not mess around with either.) But Red-Spotteds produce no such toxins that I’m aware of (which is maybe why they’re nocturnal).

One of the interesting things about a worldwide genus is where it came from. In the case of Bufo, this question has been the subject of various hypotheses for decades. The greatest diversity of species seems to be in South America and Africa. One hypothesis was that they originated in Africa, spread throughout the Old World, and then migrated to the Americas via (an earlier incarnation of) the Beringian land bridge. Another proposed the exact opposite, with a South American origin. But more recent genetic evidence seems to suggest elements of both, and yet neither, hypotheses.

Apparently Bufo originated in Gondwanaland back when South America and Africa were either still connected, or close enough for them to spread between the 2 continents. The African Bufos colonized the Old World, and the South Americans colonized the New. As the 2 groups did so, they adapted to different yet similar environments, creating morphological similarities that confused earlier researchers, and which had to be unraveled through DNA analysis.

Bufo’s story within the Americas is pretty cool: all North American Bufo species North of central Mexico appear to be monophyletic, the result of a single migration event. Central Mexico is a barrier for many species, particularly a water-loving amphibian. And even more interesting, though it’s not clear exactly when the earlier Bufo pioneers reached Central America from South America, it appears almost certain that it happened before the 2 were joined via the Great American Interchange*. This is less trivial than it sounds. Toads have water-permeable skins, and are adapted to fresh water**. Sticking most toads in saltwater is a good way to kill them. So continent or island hopping- even via rafting- by a freshwater toad is a pretty tricky undertaking. Whatever the specific details, it appears that not just Red Spotteds, but many of our most common toads in the US, have a fantastic migration history.

*Which I explained in this post.

**The so-called “Salt Toad” of California, which is actually a subspecies of Western Toad, may be an exception. It lives in salty swamps. The Marine Toad, B. marinus, cannot tolerate seawater, despite its name.

We continued down-canyon, each bend revealing a new series of plazas, pools and little waterfalls.

In March 1985, my college roommate* and I flew to Phoenix for Spring Break. We rented a car**, drove up to the South Rim, and hiked to the bottom of the Grand Canyon. At the time of course I knew next to nothing about the Grand Canyon, or the wider Colorado Plateau in general, but I was blown away by the scale and beauty of the place. In the decades following, I’ve moved out West, spent countless long weekends exploring the Colorado Plateau, often on the fringes of the Grand Canyon, and in the course of doing so learned plenty about the flora, geology, human and natural history of the region. But somehow, even after a quarter century of exploring and dinking around in the backcountry, I’d yet to return to the bottom of the Grand Canyon. So I was really, really looking forward to reaching the river.

*Yup, “Dan” from the Datura post.

**In 1985, an under-25-year-old could still rent a car. And you could reserve a bunk at the Phantom Ranch with about 2 week’s notice.

Tangent: Moments like this lead me to where-does-the-time-go type thoughts. 25 years is a long time, and I never imagined it would take so long to return. It just seems like we never have enough time. In a comment to my last post, KanyonKris mused about the benefits of slowing down the aging process so that we could enjoy more years of old age. But when I think about it, I’m not really sure the long-and-healthy-retirement-dream is the answer*. We already live for several decades- plenty of time to get around to doing, well, everything. I suspect that if we were given another couple of healthy decades, we’d just manage to suck that up with busy-time as well.

*Besides, if we all live healthier and longer, we’re all going to retire later. The demographics won’t support an ever-increasing pool of long-lived geezers retiring in their 60’s.

The irony here is that when you do something really cool, like hike to the bottom of the Grand Canyon, you remember it. I can barely remember what I did a month ago at work. And if you asked me to list things I remembered over the last decade, hardly any of the events or happenings I recalled would be work-related. Remembering stuff is worthwhile; it’s high-value. The stuff of our brains, the material us, is constantly being replaced. There really is no you*. What there is, is the story of you, the storybook you build over your lifetime and carry around in your here-right-now ephemeral head. And that storybook is written from experiences recorded as memories**. If you’re not recording new memories, if you’re not doing stuff worth remembering, then your storybook isn’t being written anymore; it’s just sitting on the shelf, no matter how “busy” and “active” you seem to be…

*I went into this in more detail in this post.

**I went into this in more detail in this post.

Dropping out and being a deadbeat isn’t the answer. Although money doesn’t bring happiness, lack of it, ironically, brings great and consuming unhappiness. The trick is figuring out the balance. That sounds easy, but it’s not, because social interaction, by its very nature, drives us off-balance. We constantly compare our attitudes, values and lifestyles to those of whom we interact with. That’s not a bad thing; we learn and grow from the examples around us, and that interaction can lead us to improve and excel scholastically, professionally, athletically and otherwise. The challenge is structuring our lives so we’re regularly and continually doing stuff in the things-we-remember category and making sure that we’re prioritizing our big high-value goals (hiking down Grand Canyon, learning a foreign language, visiting New Caledonia) alongside our big high-necessity goals (key family relationships, raising offspring, providing for loved ones.)

You can’t do everything. So if you’re going to make the balance work, you have to figure out what you’re not going to do, or spend time and cycles on. I call this Selective Disentanglement (SD), which is probably just a fancy term for “figuring out what I should blow off…” I think I’ve been getting better at SD over the last few years, and over the coming year, I’m going to try and ratchet it up a notch…

A short while later we came to the expected final pour-off, a 40-foot drop we’d need to detour around. Steve, walking ~30 feet ahead of me reached it first. He looked down, raised an arm, and called “Hi!” About a dozen people stood down below looking up, the first “others” we’d seen in a couple of days. They were rafters, hiking up from the river. There was water falling from the pour-off in a little waterfall. In the closed space of the canyon it made quite a little racket, and we had to shout to hear each other. I called down, “How far to the river?”

“200 yards- you’re there!” came the shout back.

Steve and I backed up 30 yards or so and found a place where we could pick our way up, above and around the pour-off on the West side. We traversed a bit further, and then found it- the chute from the guidebook we’d need to down-climb. It wasn’t especially technical (maybe a 5.3?) but it was exposed and far from help. We rigged a hand-line for Steve to descend first, to a ledge ~ 20 feet above the canyon floor. I followed, bringing the line with me to use for the last portion of the descent.

Side Note: If you do this trek and are a risk-averse non-climber, bring 2 ropes and 2 carabiners. There’s a good bolt for each section. The first rope should be 50 feet, the second one 20. If you’re not coming back up, one 100 foot rope (to pull through) will be fine, A hand-line is fine; you don’t need to rappel.

Two of the rafters* backtracked to watch our descent, and gave Steve helpful toehold guidance on the down-climb. When we arrived on the canyon floor they introduced themselves as Lou and David, and offered us food and beer at their camp. Together we picked our way down the last few bends of Tuckup Canyon.

*The rest of the party, which included 2 climbers (they actually own a climbing gym back home in Tennessee) managed to ascend the pour-off and day-hike further up-canyon.

I asked them how the water was (with a mind to go for a dip…) David replied, “It’s f***ing* muddy!”, and my heart leapt. In the old days, before the dam, the Colorado was pretty much always muddy/silty. But after the dam was built, the river ran with cold green waters from the bottom of Lake Powell, and that’s how I saw it 1985. But the rains of the past week had flushed mud and silt out of the side canyons, filling the river, and making it appear, temporarily at least, like its old self.

*The rafters, with their Tennessee twangs and “colorful” language, were highly entertaining to listen to. The F-word graced every other sentence. Our favorite usage-instance was when one of them, relating a story about a nude sunbather they had encountered earlier in the trip, used it in the middle of the word, “asleep”, as in “a-f***ing-sleep!)

Extra Detail: The post-dam, colder flows have led to significant changes in the canyon. Cold-water trout have replaced native Squawfish and Chub in many places and prey upon their young. At least 3 native fish species have disappeared entirely. The presence of trout in the now-clear waters has attracted Bald Eagles, who first appeared in the canyon in the mid 1980’s. Then there’s the whole beach/shoreline/vegetation thing, but that’s a whole post in and of itself…

As we walked the last little ways down Tuckup we began to hear a distant “wind” or sound. First a whisper, then building, the road of the river. Around the final bend through the Tapeats slot, the wind was accompanied by a growing light- the bright, wide-open-space daylight of the inner gorge. Steve and I walked faster toward the light and the roar, Lou and David trailing a bit behind us, like modern-day guardian angels.

And then all of a sudden the slot opened up into the inner gorge, and there was light and sky and noise and a highway of roiling, fast-moving water before us, in all of its opaque, muddy glory and power and wonder, backed on the far side by nearly vertical Tapeats cliffs, and finally, 25 years later, I was back.

Geo-Tangent: What I had expected to see, but did not, was one more geologic formation- the Vishnu Schist. Almost 2 billion years ago, in what is now Northern Arizona, a mighty mountain range built up of metamorphic rock. The world was different then; when those mountains began to rise, Earth was fresh from the Oxygen Catastrophe, when recently-evolved cyanobacteria first filled the ancient air with oxygen*, and the ensuing Huronian Glaciation**. A day was only 20 hours long, and a year contained 450 of them.

*Initially the freed oxygen combined with (oxidized) iron. But when no more could be oxidized it began to accumulate in the atmosphere, causing a mass extinction of anaerobic microbial life.

**An earlier, similar, “Snowball Earth”-type event.

The mountains rose and rose, till they towered high as the Himalayas. Over millions of years following, seas washed over and gradually eroded them down to their base. But the roots still lie there, and elsewhere in the canyon, further East, up around Phantom Ranch, the ancient rock, the Vishnu Schist, is exposed below the Tapeats sandstone, lining the inner gorge.

Extra Detail: Between the Tapeats and Vishnu formations lies the Great Unconformity- hundreds of millions of years of missing rocks that were eroded away prior to the formation of the Tapeats by advancing seas. In some parts of the canyon intervening Pre-Cambrian layers appear- Chuar, Nankoweap and Unkar- and where they do, the Great Unconformity defines the missing layers between them and the Tapeats, while an earlier gap- the Pre-Cambrian Unconformity- defines the missing layers between them and the Vishnu.

But (as I learned later) at the Western end of the Grand Canyon the Vishnu is not exposed, and the Tapeats continues clear down to the river in near-vertical cliffs. The roots of the Old World remained hidden beneath us.

Lou and David produced beers and snacks, which seemed wickedly luxurious in the middle of a backpacking trip. I kicked off my shoes and ran my toes through the warm sand while we chit-chatted about our trips. After a few minutes I got up and wandered barefoot down to the water’s edge. I stood for a moment, taking in the noise, light and tumult of the river, then stripped, waded out hip-deep, and plunged into the silty Colorado.

Note About Sources: As with earlier posts in this series, much of the geologic info came from Bob Ribokas’ Grand Canyon Explorer site, Stephen R. Whitney’s A Field Guide to the Grand Canyon and Wikipedia. Additional geologic and hydrological info for this post came from Volcanic Rocks of the Grand Canyon Area, George Billingsley, Deposition of the Tapeats Sandstone (Cambrian) in Central Arizona, Richard Hereford, and the website of the Natural Arch and Bridge Society. Info on the Red-Spotted and other toads came from David Williams’ A Naturalist’s Guide to Canyon Country, the Arizona-Sonora Desert Museum* website, Thomas Scott’s Concise Encyclopedia Biology, and The History of a Nearctic Colonization: Molecular Phylogenetics and Biogeography of the Nearctic Toads (Bufo), Gregory B. Pauly et al.

*Can you believe I have not been there yet? How is that possible?? Adding to the high-value goal list right now…

Grand Canyon Part 4: Alcoves & Hanging Gardens

From our camp at the junction of Tuckup and Cottonwood Canyons, we day-hiked up Cottonwood one afternoon. The lower part of the canyon involved a bit of scrambling and meandering around and through various jumbles of boulders. There were pools and trickles of water the whole way up. After a while we reached a pour-off with a couple of cottonwoods at the bottom, which we had to leave the canyon bottom to get around. The slope on the Northern side was loose and full of talus; we climbed it one at a time to avoid setting off a rockslide on each other.

Arizona Steve ascended first. As I followed, I could see that the sidehill placed us at the base of a second, higher pour-off that was recessed into an alcove, which Steve had already detoured into. As I paused scanning for a route on up, he called for me to come check it out. The alcove was fronted by a stand of small cottonwoods, behind which lay a pool backed by a wonderful hanging garden.

All About Hanging Gardens

Hanging gardens occur across the Colorado Plateau where continual seeps of water emerge from rock/cliff walls, creating little oases of moisture, and often shade, which support a community of plants quite different from the surrounding desert.

The reason for these seeps has to do with the hydrology of the rock layers. When you’re traveling across slickrock, it’s easy to see it as dry and waterless. In rainstorms water quickly runs off the rock surfaces (leading to flash flooding). What water does linger pools in pockets and potholes that generally dry up after a time*.

*That time of course varies by the size, depth and aspect of the pocket. Exceptionally large/deep pockets are known as “tanks” and are often year-round effective water sources.

But the rock layers are full of cracks and crevices, and some portion of rainwater trickles down into these hideaways, working its way downwards, leading to the creation of effective reservoirs or even modest aquifers within the rock. Where the crack/crevice network leads to a sidewall or cliff, the waters seep out in tickles or drips. The seep works slowly to weaken and break apart the structure of the wall underneath, causing just to break off and fall away, gradually forming an alcove.

Often this happens when the water encounters less permeable rock below, such as less fragmented/porous rock or a layer of shale, and is forced sideways. In canyon country a likely place for this to happen is at the interface of 2 distinct geologic layers. Further North in Southern Utah, this often happens where the Navajo and Kayenta formations meet. Down here in the Grand Canyon, those younger layers are nowhere to be seen, and so the Cottonwood Canyon alcove-garden, which is also a transition-layer garden, occurs among very different- and older- rock layers.

Extra Detail: Almost all hanging gardens in the Western US occur in/on sedimentary rock layers. And interestingly, some types of sedimentary rock are better “hosts” than others. Specifically layers like the Entrada and Navajo Formations, which have strong cross-bedding, which creates frequent, horizontal layers of increased impermeability, are common host formations. But Wingate- just a little below Navajo- has thinner, less clearly-defined cross-beds, and almost never hosts hanging gardens.

*For non-geology-minded Utah mountain bikers: Navajo is what you’re rolling across on Moab’s Slickrock Trail. Entrada is what you’re “surfing” up at Bartlett Wash. I did a geology-mtn biking post early this down around Gooseberry Mesa, but would love to do a broader mtb-geology post across Southern Utah. We’ll see.

When I learned this, I thought about my absolute favorite hanging garden, at the head of Twin Corral Box Canyon, which I will describe further on down in the post. Twin Corral Box, when you hike into it from the Dirty Devil, is walled with massive Wingate cliffs. But at its upper end, higher up, the cliffs are Navajo. Higher up-stream on the Dirty Devil BTW, the side canyons are overwhelmingly Navajo-walled, and as a result many of them, like the Robber’s Roost system, host wonderful hanging gardens all over the place. (One of the most rewarding things about this whole project has been the numerous ah-ha! moments when something I noticed years ago suddenly makes sense…)

Immediately above the garden is the bottom of the Redwall Formation, which we looked at in the last post. Our hike led us up through the Muav, but in between appeared a narrow and very different layer, which I believe was the Temple Butte Formation (and which I’ll describe later in the post.)

Floor

An alcove-hanging-garden- which is a specific type of hanging garden- supports an array of plants roughly divided into 3 zones. At the bottom of the alcove, by the base of the wall and often alongside a pool, are the most “normal” plants, by which I mean plants that root in soil and grow upwards. The soil is formed very gradually from fragments of the collapsing rock wall. Because the soil is limited and forms so slowly, alcove-gardens are fragile places. If the limited soil gets excessively trampled, peed/pooped in/on or otherwise abused, the plants community in this bottom layer can be disrupted or destroyed. (Exotics- like Tamarisk or Ravenna Grass, Saccharum ravennae, can also mess up this zone.)

Plants here include not just rushes and grasses, but also ferns and alcove-specific species of Columbines, Orchids and Death Camas.

Wall

The middle zone is the “wall” zone, up against the flat, damp, soil-less vertical rock wall of the alcove, and this zone supports mainly algae and cyanobacteria.

Most of the algae species that live on alcove walls are not endemic to that environment, meaning that most occur also in other environments. In a study in the late 1980s roughly 204 species of algae were found on Utah hanging garden walls, out of ~1,900 known statewide*. Of those 204, only 16 were not known to occur in any other environment than hanging gardens.

*I don’t know if this number has increased significantly since then.

But what is different about the algae in hanging gardens is the mix of species. Many are Chrysophytes, Golden Algae (pic right, not mine). The times we’ve looked at algae in this blog, we’ve generally been talking about Green Algae, which are sort of like really, really simple plants- either unicellular or multicellular- that have no specialized or differentiated cells.

Like Green Algae, Golden Algae are generally teeny-tiny photosynthetic creatures, but they’re not at all closely-related to them. In fact they’re likely about as distantly-related to Green Algae as we are. The systematics of these guys are still unsettled (and the group itself appears to be polyphyletic), but it now appears that they belong to a completely separate kingdom, the Chromists, Chromista*, which includes Brown Algae, Yellow-Green Algae and Diatoms, in addition to a few other things you never heard of.

*Way unsettled. In the 2005, an alternative kingdom, Chromolveolata, was proposed, and then in 2008 it was proposed that this group be split into 2 kingdoms. I can’t keep up. In any case, they’re way, way different from Green Algae, and they’re most certainly not plants.

Tangent: This is what is so cool about life at the microscopic level. Up here on the giganto-macro level where we reside, we perceive only a little fraction of the diversity of living things. The “kingdoms” or “kinds of living things that we can see and touch- animals, plants and fungi- appear to be just 3 of 6, 7, or maybe 11(?) kingdoms of eukaryotic creatures. And then of course there are the kazillions of prokaryotes…

Most of the time, most Golden Algae species behave more or less like Green Algae- sitting around, mostly in damp/wet places, and photosynthesizing. But here’s something cool about many of them: when deprived of light, or when they find themselves in the presence of abundant alternative food, they can switch to a predatory mode, feeding upon bacteria and diatoms. Golden Algae are sort of like little alternate-universe plants that can turn suddenly and opportunistically carnivorous.

Chrysophytes are common in fresh water, and important in lakes, where they’re believed to be a main source of food for zooplankton. Hanging garden walls seem to be a good environment for them: Roughly half of the 1,900 known algal species in Utah are Golden Algae, but they account for about 70% of the species on hanging garden walls. There’s more happening on those slimy walls than meets the eye.

Ceiling

But the most interesting and eye-catching plants occur in the uppermost zone, at the top of the wall or on the “ceiling” of the overhang, rooted directly on or right by the seep itself. Small bits of soil do form and accumulate here, providing nutrients and helping plants to root/attach. But oftentimes the substrate in this uppermost zone is neither bare rock nor soil, but tufa, specifically calcareous tufa. Tufa is a type of porous limestone created by water depositing carbonate minerals. A very dramatic example of tufa is the huge columns ringing Mono Lake in California. Calcareous tufa, the type found in desert seep-alcoves, is a type of freshwater-deposited tufa with a specific laminate structure and is less porous than most tufa types. Tufa of all types can contain lots of organic matter from debris trapped in its formation. In alcove hanging gardens calcareous tufa often forms a thin, flaking layer on the “ceiling” and sloping upper walls of the alcove.

The common plant at the seep zone is Maidenhair Fern, genus = Adantium. There are more than 200 species of Adantium ferns* worldwide, many of which have adapted to rock walls, seeps and waterfalls. Our species here on the Colorado Plateau is Adantium capillus-veneris, known alternately as Black Maidenhair or Venus-Hair Fern (pics left and above right). A. capillus-veneris has atypical, sort of “un-ferny”-looking fronds, which look almost like little Gingko leaves. They root well on calcareous tufa, and form thick, lush, bright green, hanging “mats” within the alcoves, decorating the upper walls like draperies.

*I covered the basics of Ferns, and their freaky-cool haploid-diploid generational pattern last year down in Costa Rica. Man, it is like I have a post for everything.

Another seep-zone plant was in flower. When it first caught my eye I thought it some type of Gilia, but it was actually Scarlet Lobelia, Lobelia cardinalis (pic right*). Lobelia belongs to the Bellflower family, Campanulaceae, and probably the most closely-related thing to it we’ve looked at previously was Harebell last summer up in Glacier NP. Scarlet Lobelia favors moist environments such as stream banks, bogs and meadows in addition to alcoves. Its red, deep and narrow-tubed flowers are pollinated by Ruby-Throated Hummingbirds (like Gila). It was used medicinally by Indians to treat bronchial ailments (including asthma) and supposedly syphilis.

*Sorry- for some reason I only snapped this one rather low-quality shot. I have no excuse except that I take lots of photos when I hike, and don’t really know at the time what- if anything- I’ll blog about.

Tangent: I say “supposedly” because I can’t count how many plants I’ve read about that Indians allegedly used to treat syphilis. Seriously, it has to be dozens. What I wonder is whether any of these plants actually eased the symptoms of the disease (certainly none of them cured it) or whether the Indians were just so desperate that they pretty much tried anything. And in fairness, Syphilis appears to have been a much more virulent (and horrible) disease during its first recorded few decades in Europe than it was by the later 16^th century, by which time it was basically the disease it is today.

Syphilis BTW has a fascinating and still unsettled history. For a long time, it was cited as a classic example of a New World disease spreading to the Old World. But other researchers believe that it was already present in both New and Old Worlds. Still other researchers hypothesize that it evolved in the Old World, was carried across the Beringian land-bridge with Paleo-Indians, and then re-encountered by European explorer. The timing of the disease’s history in Europe is tricky; the first major outbreak was in 1494, which would mean that if it was a New World pathogen, it pretty much would have had to arrive in Europe via Columbus’ first voyage.

Nested Tangent: I sometimes pick up a tone of explanation or justification in traditional New-World-Origin accounts of Syphilis. Yes, we gave the Indians Smallpox and a whole bunch of other diseases, the story goes, but hey, they gave us syphilis, as though it somehow balances things out.

Today in the age of AIDS, syphilis is farther down on the list of most folks’ STD-worries, yet another of the multitude of terrible diseases that’s largely been beaten in the First World, allowing so many more of us to live long enough to succumb to cancer. I wonder, if they ever cure cancer, what we will start dying of next?*

*I’m reminded of the old Red Foxx line (paraphrasing): “All these health nuts are going to feel stupid someday, lying in a hospital bed, dying of nothing.”

Scarlet Lobelia’s medicinal properties- whatever they are- likely are a result of the plant’s alkaloids, which can be toxic, and probably shouldn’t be messed with. BTW, you won’t find this flower in hanging gardens up around Moab or Canyonlands; though it’s common in them around the Grand Canyon, Glen Canyon NRA and Zion, it doesn’t appear in hanging gardens further North.

Alcove hanging gardens always seem quiet, contemplative places. When I’m in one I always feel as though I should speak softly and be respectful somehow. I don’t know that this feeling stems from any karmic-greenie Earth-vine or anything, so much as they half-consciously remind me of cathedrals, with their dim light, still, cool air and vaulted ceilings. The Cotton Canyon Alcove is small- maybe 30 feet high, but I’ve stood in others that are huge. The side canyons of the Dirty Devil in particular contain a number of spectacular ones, the largest and most amazing of which lies at the head of Twin Corral Box Canyon, with a ceiling of well over 100 feet high.

Alcove-gardens are cool, refreshing places offering a break from the sun and heat of the surrounding desert. In the really large ones, the cool, damp air can induce a deep chill within 15 minutes or so, driving you to fumble around in your pack for an extra layer, or retreat back into the sun. Our small alcove was just perfect though, and we found ourselves lingering for a bit. These places have an out-of-time feel to them; it’s easy to be surprised at how much time you’ve dawdled away if you get distracted or don’t keep an eye on your watch.

Tangent: Yes, I backpack with a wristwatch. I do almost everything with a wristwatch. Once on a trip along the Dirty Devil about a decade ago, Steve and I decided we wouldn’t bring a watch. After all, we were backpacking, we had all day, why be constrained by something so civilized as a watch? Why not wake when it gets light and go to sleep when it turns dark? Isn’t that the right, “natural” way to live?

It turned out to be a terrible idea. The trip was in October- a time of shortening days- and we spent most of the trip in deep-walled canyons under overcast skies. We never could never tell what time it was, and as we didn’t want to get stranded out day-hiking away from our base camp after nightfall, we really needed to know what time it was. As a result, we must have asked OCRick- who accompanied us on the trip but abstained form our little back-to-nature-wristwatch-rebellion- the time at least 30 times a day.

Continuing up around and above the alcove was the only tricky part of the hike, involving an exposed scramble up a series of ledges on the North side. Fortunately the rock of these ledges was distinctly different from that below or above- an extremely rough-surface, abrasive stone that was wonderful for free-climbing*. I’m pretty sure this was the Temple Butte Formation, a relatively narrow band between the Muav and the Redwall, that tends to be thicker in the West End of the Grand Canyon**.

The Temple Butte Formation is interesting in that it appears in channels in the underling Muav layer. The channels may have been streams or estuary channels within with deposits accumulated that became the Temple Butte rock some 350 – 400 million years ago.***

*But would be awful to fall or slide on.

**And which I either missed (entirely possible, as this geology stuff is still pretty new to me) or is absent in the main drainage of Tuckup Canyon.

***Different sources give really different ages for this layer.

After ascending 2 sets of ledges and crawling between 1 more (pic right), we were atop the alcove* and back in the Redwall, through which we continued up a drainage full of gullies, chutes, pockets, plazas and pour-offs. Every bend revealed some interesting little plaza or pool or minor obstacle (pic below, left)**.

*There’s a bolt at the top of the alcove. Rappelling down would be easier and safer than the ledgy down-climb

**This, BTW, is why hiking narrow canyons is so great to do with kids. The constant surprise-around-every-corner aspect and frequent scrambling opportunities distract them from the mundane-ness of trudging along for hours.

Eventually we broke out of the Redwall and the canyon, now just a shallow gully on the giant Esplanade terrace lined on either side by low shale hills. A short while later we crossed the Tuckup trail and arrived at the Cottonwood Spring. The Esplanade is dotted with a number of springs like this one. Here the hard capstone creating the terrace* serves at the hydrological barrier forcing the water to the surface.

*Which I described in Part 2 of this series.

The Spring was marked by a stand of young Cottonwoods (pic right). Standing snags suggested that much larger Cottonwoods used to shade the spot and we wondered why none of the giants still lived. At several point on our hike up we’d come across huge old trunks, even below the alcove, reminders of the force of floods that must scour the canyon.

The ground all around the spring was damp and grassy, and the grass here had a strange appearance, almost hazy, as though you couldn’t focus on it. On closer examination the “haze” was an abundance of super-fine stalks bearing seeds, like nothing I was familiar with.

Back home later I learned this was Western Panicgrass, Dicanthelium acuminatum (pic left, not mine), which is common across much of the US, but which I’d never before noticed in such concentrations. Panicgrass, BTW, belongs to the same grass sub-family, Panicodeae, as our old friend Crabgrass. While Crabgrass is an Old World native that has become a naturalized pest in the New World, Western Panicgrass is a New World native that has become naturalized pest in the Old.

Arriving at the spring we suddenly felt beat, and lazed for a while in the shade before heading down. After the Temple Butte down-climb we stopped in at the alcove again to pump some water, then picked our way down-canyon through lengthening shadows back to camp.

Next Up: The River.

Note About Sources: Geologic info for this post came primarily from Bob Ribokas’ Grand Canyon Explorer site, Stephen R. Whitney’s A Field Guide to the Grand Canyon and Wikipedia. Hanging Garden Info came from David Williams’ A Naturalist’s Guide to Canyon Country, and On The Distribution of Utah’s Hanging Gardens, Stanley L. Welsh, from the Great Basin Naturalist*. Welsh’s paper provided the algal species distribution info, but was apparently published before(?) the classification of Chrysophyta as Golden Algae, for which my primary source was the University of California Museum of Paleontology site. Panicgrass info came from the Master’s thesis, A Morphological Invesitagtion of Dicanthelium Section Lanuginosa (Poaceae), Justin Ray Thomas, Miami University.

*Now the Western North American Naturalist. Man, there is like a publication for everything.