Birds, Hearing and Ears

Note: This is my 400^th 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. 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.

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.

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, and 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), which 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.

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 cochlea, 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.

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!)

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.

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 1/20^th of a second to recognize it. Birds can do so in just 1/200^th 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. 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.

Thanksgiving Desert Hiking Part 3: Big Footprints

The morning after Thanksgiving we slept in and took our time getting going, lingering over the complimentary hotel breakfast* waiting for the temps to climb over 20F.

*Before I had kids I used to diss those free breakfasts. Now we are all over them- the most cost-effective way to fill the bellies of 3 children around. I only wish our kids were like reptiles- stuff them with half their body-weight in waffles and fruit loops and don’t worry about feeding them again for a week. Unfortunately, no matter how many waffles they eat, they’re hungry again 45 minutes later.

After breakfast we packed up, checked out and headed out of town. Driving North up US191 from Moab is like a drive through time: you cross the Colorado River driving past 290 million year old Honaker Trail rock and by the time you reach I-70 you’re rolling over 80 million year old Mancos Shale.

Side Note: Just a few miles North of the turnoff for Arches, on the way up to the turnoff for Dead Horse Point and Island In The Sky, you pass all these gnarly, convoluted, deep-red cliffs lining the West side of the highway. The shapes looking almost haunting, and sometimes out of the corner of your eye as you’re zipping by at 70 MPH you think you catch a glimpse of a form, or even a face, trapped in the rock. The “face”-glimpses are always convoluted, miserable-looking and vaguely Dante-esque, like those Nazis who looked inside the ark in the first Indiana Jones movie. (Right before they melted.) Anyway, years ago, when I used to do weekend Moab trips from the Denver area and knew absolutely nothing about rocks, I called this section the Wall Of Tortured Souls (WOTS).

The WOTS is actually part of the Cutler Group, which was laid down in Permian times, between 240 and 290 million years ago. Like most of the other main geologic formations around it consists of several distinct sub-units, or members.  The WOTS is composed specifically of the Organ Rock Shale member, which was formed from a series of highly oxidized (hence the reddish color) layers of mud. Organ Rock is always striking, and shows up in some spectacular spots. The sloping bases of the massive buttes in Monument Valley are Organ Rock. When you’re riding the White Rim, and look off the edge and down below into Monument Basin (pic right), those freaky, free-standing “totem pole” pillars are also Organ Rock. It’s a soft stone, eroding quickly and dramatically. The Monument Basin pillars are each capped by a fragment of White Rim Sandstone (stuff you’re riding on), which slows the erosion of the pillar below.

Up and up we drove, past Chinle and Moenkopi, Wingate and Kayenta, Navajo and Entrada. Eventually the rocks melted away and we continued North across the high rolling plain toward I-70 that always seems so dreary after the geo-spectacle that is Moab. But a few miles North of the turnoff for Klondike Bluffs, we turned off the highway and traveled East for a couple of miles over clay roads to the base of a low rocky ridge. We parked, hiked across the rock for 5 minutes, and found what we were looking for.

The rock layer above the Entrada is the Morrison formation. Laid down ~150 million years ago, the formation covers a huge piece of the Western US- from the Dakotas to Arizona. Morrison isn’t particularly spectacular sandstone. Oh, it’s pretty enough in places like Dinosaur National Monument and numerous outcrops just West of Denver, but it’s a cracked, beat-up modest-looking kind of rock. Its outcrops have none of the wow-factor of Wingate cliffs, Navajao dunes or Entrada waves and arches. But what the Morrison does have, and is particularly well-known for, is fossils. Dinosaur fossils.* But we weren’t looking for fossils; we were looking for tracks.

*It’s also rich in uranium.

Unlike fossils, dinosaur tracks- and especially “walkways”, or a procession of tracks- are rare in the Morrison. Copper Ridge North of Moab is one of only two known Morrison formation walkways in Utah. The site contains the tracks of 5 different dinosaurs (though only 3 are really easy to pick out.) Dinosaur tracks are always cool. It’s one thing to look at a rock and know how old it is, and it’s even cooler to come across a fossil of some kind, to see the impression, the remnant of a creature that lived hundreds of millions of years ago, when everything about the world was different- the climate, the geography, even the oxygen content of the atmosphere.

But somehow to see a footprint- better yet a walkway of successive footprints- is cooler still. Here’s evidence of some forgotten creature doing something. These giant prehistoric monsters actually moved, right here, where we’re standing.

All About Dinosaurs

Everybody knows that dinosaurs were the dominant vertebrates on the planet for about 160 million years. At a high level the dinosaur family tree broke out into 2 different groups- Ornithischia and Saurischia. The Ornithischians were all plant-eaters and included dinosaurs like Triceratops, Stegosaurus and Ankylosaurus. Saurischians included both meat-eaters and plant-eaters. The Saurischian plant-eaters, known as sauropods, were long-necked animals that walked on all fours and included the largest dinosaurs. Brachiosaurus, Diplodocus and Apatosaurus* were all sauropods. The meat-eaters, known as theropods (which also included some plant-eaters and omnivores) were 3-toed, and generally- but not always- had shortened forelimbs. Many species were bipedal. T. Rex, Velociraptor, and Allosaurus were theropods.

*Called Brontosaurus when I was a kid.

Extra Detail: The Velociraptors in Jurassic Park were way oversized; an adult would’ve only been about waist-high. The dinosaur used to model them for the movie was a related type, Deinonychus. Utahraptor, though, might’ve been an even better match size-wise.

Theropods are the only dinosaurs not to have become extinct at the end of the Cretaceous. Birds are believed to be a surviving branch of the Coelurosaurs, the group of theropods that included both T. Rex, and the above-mentioned raptor-type dinosaurs. Crocodilians are not dinosaurs, but archosaurs, a group which also includes dinosaurs.

The 5 dinosaurs at Copper Ridge were 4 theropods and 1 sauropod. Paleontologists can’t be sure which species they were, but they have some pretty good suspects, based on the size and shape of the prints, the distance between the prints, and the rock formation (i.e. Morrison is a Jurassic formation, so they have to be Jurassic species.) Sauropod prints are less common that theropod prints*. The sauropod prints here are believed to have been made by Camarasaurus, Apatosaurus or Diplodocus, thought to have been 12 feet high at the hip, and 70 feet long from nose to tail.

*I’ve seen dinosaur prints several other times, but only once stumbled across one by accident. It was a theropod print, about 8 inches long which I came across hiking out of Coyote Buttes. I only noticed it because it was late in the day and the low sun-angle produced a shadow in the print.

Tangent: One of the most remarkable things about dinosaurs to me is the high level of interest in them. Awesome Wife and I discussed a few different possible destinations/ activities for the day after Thanksgiving, and picked Copper Ridge primarily because we knew that dinosaurs are always a hit for kids (especially boys.) Closer to home, the local dinosaur museum is a standard rainy-Saturday backup; we’ve been there probably 30 times. There are countless museums, movies, toys and games related to dinosaurs.

The same holds true by and large for adults. There have been oodles of movies, books and time-travel stories around dinosaurs. I’m hard-pressed to think of a time-travel book/movie in which the protagonists are transported to say the Eocene, or the Carboniferous, or Snowball Earth. Dinosaurs were interesting and important and all, but from a history-of-life standpoint, it’s hard to argue that they were that much more significant or important than many, many other prehistoric life forms. Certainly the evolution of the eukaryotic cell was more significant, complex, world-changing and just head-scratchingly amazing, but proterazoans just don’t make good antagonists. Dinosaurs just have an almost unbeatable level of drama and awesomeness on a scale we can relate to that catches the attention of people- not just paleo-geeks, but regular people who might otherwise not give prehistory another thought.

Nested Tangent: The only other past-time-period-fauna that comes anywhere close is probably the late Pleistocene, which has spawned a fair number of books, toys, games and movies. Part of this could be (or should be) due to its recency, and part of it could be (or should be) due to our own species’ possible role in the demise of these creatures. But I suspect most of it is due to the Wooly Mammoth and Saber-toothed Tiger, the 2 “Ice Age” mammals everyone knows about, which is sort of a shame in that they were just 2 of a cast of dozens and dozens of amazing, recently-extinct, very big mammals.

This everyman-interest in dinosaurs is evident even in the anti-science community. Dinosaur displays are standard fare “creation museums” (pic left, not mine, display of Adam & Eve* in the Creation Museum in Petersburg, KY) where they’re often depicted peacefully coexisting with early humans (presumably within the last 6,000 years.) There are displays of humans riding dinosaurs (pic above, right, not mine either), and vegetarian T. Rexes. But you never see a diorama of a caveman riding an entelodont, or a caveboy feeding an aquarium full of trilobites, or chasing dragonflies with 2-foot wingspans.

*Two things about this display. First, I must note that Adam’s beard looks Way Awesome, and actually not too dissimilar to mine. Second, Eve looks exactly like all my babysitters from the 1970s- pleasant, kind, and disturbingly sort of hot in an I-feel-awkward-to-be-checking-her-out kind of way.

Anyway, I guess the disproportionate attention given dinosaurs is a good thing, in that it provides an approachable and exciting glimpse of paleontology to millions of folks who otherwise wouldn’t give it a second thought.*

*Kind of like geology or botany or hydrology or most of the other things I blog about…

Sauropod Tracks

The sauropod tracks include both front and rear prints. Rear sauropod feet had a fleshy pad toward the back, and so the prints are generally round and amorphous, kind of like an elephant print. Their front feet were very different; they walked sort of like a ballerina on their toes, and the print is more of an arc, or semicircle.

The front prints are often trampled by the rear prints, but I was able to pick out at least 1 front print clearly in the rock. The prints enter the wash at an angle, cross it, and then turn roughly 60 degrees to the right/East, following the wash for a few more steps.

This right here is, to me, the absolutely coolest thing about the Copper Ridge walkway. The dinosaur turned. It changed its mind. The tracks are 150 million year old record in the rock of a living creature actually making a decision in its (admittedly small) brain.

Theropod Tracks

The theropod tracks- though easy to pick out- are trickier to make sense of. 3 of them overlay the sauropod tracks and though it’s not hard to find some, it’s tough to tell who’s who. But the 4^th set of tracks stands alone about 15-20 feet to the West, crossing the wash at about a 45 degree angle. The prints are up to a foot long, suggesting a hip height of ~5 feet. Allosaurus is the top candidate; it stood 15 feet tall and weighed up to 2 tons.

The Allosaurus(?) tracks don’t turn, but they also hint at a story: the gait is irregular. The step of one leg is ~5 feet, the other only ~4 feet. This limp suggests the dinosaur was injured, either recently, or hobbled from an old wound healed imperfectly. Another idea is that maybe it was carrying something heavy- like a hunk of prey in its jaws.

Copper Ridge is a quick stop and a cool site. Having passed by probably close to a hundred times over the past 20 years, I felt silly for not having stopped by sooner. If you’re planning a trip to Moab, or even passing by on I-70- and can spare even 30 minutes, make sure you stop by. And speaking of stops…

Next Up: The Rock Art Extravaganza of Thompson Wash

Note about sources: Most of the info for this post came from Geology Underfoot in Southern Utah, Richard L. Orndoff, Robert W. Wieder and David G. Futey. Additional info came from Canyonlands Geology – A Visual Toolkit, Jerry Shue, Neal Herbert and Barbara Webb, the College of Eastern Utah Prehistoric Museum* in Price, Utah, and the Louisville (Kentucky) Portal website.

*We stopped by, later that day on the drive home, another great stop I’d passed by dozens of times previously without ever having checked out. It’s a perfect 1-hour interruption for a family drive home from Moab.

Steiner100 Part 2: Mallows, Gilia and Rattlers

The mid-mountain trail between the Canyons and Park City is one of my favorite parts of the Steiner100, and the flowers have changed a lot since I rode it 2 weeks earlier.

Sticky Geranium, Richardson’s Geranium and Leafy Jacob’s Ladder now dominate the understory. There’s also a newcomer- Mountain Globemallow, Iliamna rivularis (pics right, left). I like this guy because it’s both attractive and a bit unusual. It’s never super-common, but occurs in isolated patches through the Aspen forest. And it’s not particularly closely-related to anything else around it. The closest thing we’ve looked at to it is our old friend Desert Globemallow, back down in St. George. Mountain Globemallow seems like its mountain cousin, adapted for a cooler, wetter world.

Side Note: There’s another flower that looks a lot like this that’s been blooming for about 2 weeks about a thousand feet lower, down around Jeremy Ranch, and for about a week I thought it was the same thing. But it’s not- it’s Rocky Mountain Checkermallow, or Salt-Spring Checkermallow, Sidalcea neomexicana (pic right). It’s another close cousin, and at first glance it’ll fool, you, but the stamens are way different.

Down To Six

When Mid-Mountain trail spat us out in Park City, we lost one more of our group. The remaining 6 of us turned upward, Westward and homeward in the late afternoon heat as we began the long, seemingly endless climb up onto the Wasatch Crest.

Tangent: Our Park City drop-off was none other than Fast Jimmy, on whom the heat had taken a bit of a toll. But this is a great time to mention that FJ has had a busy cycling season, that’s been reflected in his waistline. Since our White Rim adventure- just 6 weeks ago- FJ has lost 15 lbs! Go Fast Jimmy!

When we finally crested Puke Hill at 9,600 feet, we re-grouped and caught our breath. The flowers here were great as well, and what was particularly interesting was that much of the Scarlet Gilia up here was a light pinkish white. I’ve blogged about Scarlet Gilia a number of times; it’s beautiful, common and easy to ID. But one of the most fascinating things about this guy is that the flowers on individual plants and groups of plants actually lighten in color later in the season, and apparently they do so in response to a pollinator shift. Early in the summer, Gilia’s primary pollinators are Hummingbirds. But as the summer progresses, the Hummingbirds move on, and the plant relies more on the remarkably-convergently-evolved (and equally-long-proboscised*) Hummingbird Hawkmoth. Hawkmoths, who of course have a completely and radically different system of color vision than birds, prefer lighter-flowered colors, and the color shift of the flowers appears optimized to attract their attention.

*Can I make a word out of that?

Side Note: Unfortunately, despite the fact that the lovely, light=pink “Scarlet” Gilia were everywhere along the Crest, I only snapped this one, blurry, while-rolling, photo (right). What can I say- by mile 80-something it gets harder to make photo stops.

Racing along the crest is always thrilling, but doing so in the early evening feels like chasing the sun back into the Salt Lake Valley. The miles rolled by, and even after 80 miles we felt fast and confident, threading our way smoothly down “the Spine”, past Desolation Lake and back toward Mill Creek.

There’s a point along this stretch where you can look off into the distance and see the Great Salt Lake, and the salt flats beyond. In the late afternoon it’s obscured in a white-hot summer haze, a reminder of the 100+F temps in the valley below. After all these years, this is still my favorite view of the valley, and it makes me think how all of the streams and springs that feed the green lushness around me will eventually finish their journey, just 30 miles away and 5,000 feet below: evaporating on a white-hot playa, under scorching desert sun. It’s the weird combination of beauty and harshness that is the Wasatch Front, wrapped up in a single picture.

Down, down, down into Mill Creek Canyon, through Spruce and Fir, past Fitweed and Flax, we sped through meadows and forests till we popped out at the Big Water trailhead and bombed down 3 miles of twisty asphalt before jumping on Pipeline trail. Almost 4 weeks ago I blogged about this stretch of Pipeline, mentioning the tall grasses brushing against my shins. On Saturday they brushed my arms. The evening air had started to pool in the draws, giving us momentary respites from the heavy hot air of the day. (Another blurry pic- sorry- along Pipeline, left) We were almost home.

Brush With Danger!

But at the top of Rattlesnake Gulch, our exit down to the pavement, I looked at my computer and did some quick math. I would finish a couple of miles short of a full century, and I talked one of our remaining group- young “Ian”- into pedaling out to the Mill Creek overlook and back for an extra couple of miles.

On the way back, pedaling quickly, I spied a Gopher snake crossing the trail. In a hurry, and calculating that I’d miss it, I kept rolling.

Only… it wasn’t a Gopher Snake. As it crossed the trail it quickly coiled and rattled, as I passed it by less than a foot at 12-15 MPH. My heart skipped a beat, but he didn’t strike. I yelled back at Ian, but it was too late- he’d already rolled past as well, only realizing it presence when alongside it.

Utah has 7 species or subspecies of Rattlesnake. The one I blogged about last year, down by the Dirty Devil, was a Midget Faded Rattler, Crotalus viridis concolor. Down around St. George, you could conceivable get bit by 1 of 4 different species of Rattler. But up here along the Wasatch Front, we have just one- the Great Basin Rattlesnake- C. viridis lutosus. C.v. lutosus isn’t at all unusual; if you hike or bike often enough in the Wasatch between 5,000 and 9,000 feet you’re eventually going to cross paths with one*.

*And I suppose if really often enough, get bit, eventually…

All Rattlesnakes are venomous, and inject venom through frontal, hinged, hollow fangs. The venom is a modified saliva, and consists of 2 principal components: neurotoxin and hemotoxin. Neurotoxins act on nerves and cause pain and paralysis. In other snakes, such as Coral Snakes, whose venom is primarily neurotoxic, bites can lead to death through paralysis and respiratory failure. But the neurotoxic component in Rattlers isn’t that powerful. Rather the more problematic component is usually the hemotoxin, which disrupts blood-clotting, destroys capillaries and muscle tissue, and clogs the lymphatic system with dead cells. Although Rattlesnake bites are rarely fatal, permanent scarring muscle damage and even loss of limbs are not uncommon.

Tangent: Rattlesnake bite is the probably the one backcountry potential mishap for which I don’t have a good plan. The standard advice is Seek Medical Attention. That’s less-than-satisfying advice in the desert canyons of Southern Utah, where cell service is non-existent, and return to one’s vehicle can take a full day+ when healthy… The various snakebite kits are generally considered worthless at best, harmful at worst. If any reader has a plan or product they can recommend (and have used) I’d love to hear about it.

The 6 of us regrouped down at the bottom of Rattlesnake Gulch* and rolled home along Wasatch Drive. It was a great Steiner100, the best yet. But don’t take it from me; take it from Aurora Coryalis and Hunky Neighbor:**

*Yes, it’s really called “Rattlesnake Gulch.” Talk about a place where one ought to be careful of Rattlers…

**Any SLC locals know what the deal is with that garage?

By Popular Demand: The Creepy-Crawly Post!

So as everyone who reads this blog knows, the Watcher-Family-Unit had an outstanding vacation last month in Costa Rica. I blogged about the amazing mammals, birds and plants we saw down there, but unfortunately, none of those posts was a good place to blog about the innumerable Creepy-Crawlies we encountered on our trip. And so I’m belatedly doing this Special Bonus Post to give equal time to the various things we saw that slither, scuttle and/or sting.

But first, I must define the term Creepy-Crawly. For purposes of this post, to be a Creepy-Crawly, a creature must meet 1 or more of these 4 strict scientific and highly technical criteria:

1- It’s an invertebrate

2- It’s a reptile

3- It’s something that can sting, inject venom, harm, cause pain to, or otherwise make miserable a human being.

4- It’s something that, if your kid sister found it her bed, she would Totally Freak Out.

I recognize that this list is a bit broad (and in fact as I review it, I realize that technically my first wife would qualify*) but hey, it’s good enough.

*Meets criteria 3 & 4.

There honestly wasn’t a single day of our vacation that we didn’t encounter at least one exciting Creepy-Crawly. On the very first day, on our drive down to Quepos, we hit a home run with the kids by stopping at the bridge over the Rio Tarcoles, probably the best-known Crocodile-watching spot in all of CR. For years, tourists have stopped, watched, and (illegally) fed the several dozen Crocodiles that congregate under the bridge. Here’s a short video of another tourist dropping a road-killed Boa Constrictor into the Croc-infested waters below.

Side Note: Yes, even the road-kill in Costa Rica is exciting; that really was a Boa he dropped.

Crocodiles, Alligators and Caimans

The order Crocodilia has been around for more than 80 million years, and includes 3 families. The first is Gavalidae, which includes only 2 species, Gharials and False Gharials, native to Malaysia and India respectively.

The second is Alligatoridae, and this includes Alligators and Caimans. Alligators are what you’re likeliest to see in Florida. Though there used to be dozens of different species, there are only 2 species today, the American Alligator, Alligator mississippiensis, and the Chinese Alligator, Alligator sinensis. Alligators are the only crocodilians whose upper jaws are bigger than the lower jaws, and therefore completely cover the lower teeth when the mouth is closed. So if the mouth is closed and you see lower teeth, it’s not an Alligator. A. mississippiensis is native to the Gulf Coast/Florida and doesn’t make it down to Costa Rica.

Caimans are a bit smaller than most Crocs and Alligators, generally no more than 2.5 meters in length. There are 6 species, all native to South America. One, the Spectacled Caiman, Caiman crocodilus, makes it up into Central America and Costa Rica. Caimans were on Bird Whisperer’s “Target List”, and we looked hard for them, but to no avail.

The third family is Crocodiles. There are over a dozen species of Crocodile, spread across Asia, Africa, North & South America and Australia, and these include the biggest, meanest and most dangerous Crocodilians. The one found in CR is the American Crocodile, Crocodylus acutus. C. acutus grows up to 6 meters in length, and can swim up to 20 mph. Attacks on humans are unusual, but not all that rare. (Our guide in Quepos knew a fellow who’d lost a leg in an attack last year.) Crocodiles are generally more territorial, larger, and likelier to attack humans than Alligators. But (thankfully) the Crocs likeliest to attack humans are the Saltwater and Nile Crocodiles, found only in the Old World. Crocs are of course a regular threat to dogs in CR; as we returned from a Mangrove tour, a dog scampered among the reeds along the bank, chasing something. I overheard our guide say to the boatman, “No dura tres dias mas…” (“He won’t last another 3 days…”)

It’s one thing to see Crocodiles from the safety of a bridge; it’s another to find them lurking in the mangroves. Check out this shot on the right, and then see if you can find the one hidden in the pic below on the left.

2 other interesting differences between Alligators and Crocodiles: Alligators tolerate cold water (down into the 40’s F) far better than Crocodiles, which is why Alligators have done so well in the Southeast. But Crocodiles handle salt water better than alligators, which is why they’ve managed to colonize a number of Caribbean islands. In fact it’s thought that the small population of Crocodiles in Florida (~1200 individuals) arrived by island-hopping from Cuba during a previous ice age (when sea levels were lower.)

Spiders!

A few hours after our stop at the bridge, we arrived at the Blue Banyan Inn. As we were walking past the lobby/pavilion on the way to our cabina, a glint of glittering gold caught my eye. It was a spider web, a huge web, maybe 4 feet across, with thick, well-defined strands that caught and reflected the afternoon sun. And in the center of it was the most stunning, beautiful spider I’d ever seen- a Golden Orb Spider, Nephila clavipes.

There are 2 creepy things about Golden Orb Spiders. First is its size: about 4-5” in leg-span, and the abdomen alone is between 1” and 1.5”. The females are way bigger than the males. In fact in this pic- get this- I got the female and the male. Despite their size, they’re not particularly dangerous; though their venom contains neurotoxins chemically similar to those in Black Widow venom, they’re far less powerful, and the bite is usually no worse than a bee sting. (For a description of the neurotoxins in Black Widow venom, see this post.)

The 2^nd creepy thing is the web- it’s tough. After we settled into our room and had a swim, I went for a run. The old 4WD trail I was running on quickly deteriorated into a partially-overgrown jungle track (looking like pic on right), but I persevered. (Probably not my brightest move, as we’ll see when we get to snakes.) A few dozen yards later I felt a sharp yank across my thighs, as though I’d hit a trip wire. Quickly looking around, I saw a Golden Orb female scuttling up a broken web-strand and into the brush. Though the web gave way immediately to a running 175 lb human, it was the strongest spider-web I’ve ever felt. (Supposedly pre-Columbian Americans used them for fishing lines.)

The distinctive yellow tint of the web is caused by a combination of 4 compounds, and is thought to serve 1 or 2 possible functions. The first is camouflage in jungle brush; the second is to attract bees, which are often caught and consumed by the spiders. We saw plenty of Golden Orb Spiders in and around Quepos and Manuel Antonio, but none in the high country. “Golden Orb” BTW, refers to N. clavipes’ web, not her abdomen.

The lowland coastal jungles had many other interesting insects. One of the fascinating things about ants and termites in the neotropics is that they often build their nests in trees (pic left). If you’ve been to Central America, you may have notice that trees in parks and in towns are often painted white around the base, for the first 3 feet up or so. Supposedly the paint serves to dissuade ants and termites from ascending the trunks and colonizing the trees.

Tangent: On my previous CR trip with Bird Whisperer, I ate a live termite, at the encouragement of a guide. It tasted faintly of peanutbutter.

Nested Tangent: “Peanutbutter” is one of those words that will drive you crazy in Spanish. In Mexico it’s “Crema de Cacahuate.” But in Spain, it’s “Maneca de Mani”. In a Costa Rican supermarket I asked for it by both names, and received quizzical looks until the clerk realized I was looking for “Crema de Mani.”

Another word that’s like that in Spanish, and one that comes up for us a lot when we travel, is the word for non-identical twins (pic left = ours.) The word for identical twins in Spanish is “Los Gemelos.” But different Spanish speaking countries have completely different words for non-identical twins. In Mexico, it’s “Los Cuates”, in Spain, “Los Medizos”, in Cuba, “Las Jimaguas”, and in Colombia and Venezuela, “Los Morochos.” In Costa Rica, it’s just “Los Gemelos”; apparently like us English-speakers, they use the same word for both types of twins.

Snakes!

OK, let’s get back to reptiles. Here’s something else we saw in the mangroves- a Mangrove Boa (pic right). This guy lays about during the day, then prowls through the branches at night, hunting for birds, monkeys and other snakes. What happens when it catches one? We’ll get to that in a moment. We saw a few other snakes in the wild on our trip, but (much to the dismay of Bird Whisperer) no venomous ones. But venomous snakes are common in Costa Rica, and we learned quite a bit about them while we were there.

When we checked into the Blue Banyan, we received only one warning: kids stay out of the brush. Every gardener or agricultural worker we saw in and around Quepos wore knee-high rubber boots. (Now you know why my jungle-run probably wasn’t so smart…)

In Costa Rica- a tiny little country- about 600 people get bit by venomous snakes every year. Fully half of those bites are the work of just one species: the Fer-de-lance, Bothrops asper. The Fer-de-lance does not have the deadliest venom of Costa Rican snakes- that distinction goes to the Coral Snake. But it is far and away the most dangerous, as it is aggressively territorial.

If you’re like me, and you do a lot of hiking in the Western US, you’ve probably had a Rattlesnake rattle at you. And probably, like me, you jumped back and thought “Phew- close call!” But you probably weren’t bit; the Rattlesnake was warning you off. Now imagine if instead of warning off, that rattler came after you and tried to bite you. That’s what a Fer-de-lance often does.

Tangent: I’ve had oodles of run-ins with Rattlesnakes. See this post for a description of backpacking in a Rattlesnake-infested canyon in Southern Utah. But my all-time best Rattlesnake story is this: in June 1996, I jumped my mountain bike over a rattlesnake* lying across the trail as I was descending the singletrack off of Lewis Peak up in Ogden.

*Not as crazy as it sounds. I was moving at 20-25 mph and didn’t see it till it was 6-10 feet in front of me. It was bunny-hop or roll over it, and fear made me hop before I could think about it. So really, not crazy at all. Not like this or anything…

But here’s the bright side of the story: of those 600 bites per year, only 1 or 2 are typically fatal. Costa Rican hospitals and clinics are extremely well-stocked with antivenins, and the fatalities that do occur are most often due to bites that happen in extremely remote parts of the country, from which a medical facility can’t be accessed quickly enough.

Lizards!

CR also has plenty of cool lizards. Here’s a Common Basilisk, Basiliscus basiliscus, (pic left, not my best photo) we spotted basking in the mangroves. It’s also known as the “Jesus Christ Lizard” because 3 days after it dies it rises from the dead. Haha! A little Holy Week humor for you there. No, it’s called the JC Lizard because it’s able to run across the surface of the water for distances of up to 20 meters before sinking (after which it swims along just fine, though not as quickly.)

Iguanas are also common in CR, as is this guy, which looks like an Iguana, but isn’t. It’s a Ctenosaur (pronounced “tina-sore”), specifically a Black Ctenosaur, Ctenoaura similis. It’s native from Mexico to Panama and in CR you’ll see them all along the Pacific coast.

Tangent: It’s also been introduced (as escaped/discarded pets) into both Texas and Florida.

When you see a Black Ctenosaur, it’s pretty much always like right here- basking on the sun. But when it wants to, this guy can haul ass. C. similis is the fastest lizard on the planet, and has been clocked at a max speed of almost 22 mph.

Special Side Note – Sepentario Monteverde: Though this blog focuses on critters in the wild, I’d be remiss if I didn’t mention the amazing reptile zoo up in Santa Elena, Serpentario Monteverde. This place was a total 100% hit with the Trifecta, and afforded us an opportunity to see several snakes we didn’t see in the wild, including the Fer-de-lance, Coral Snake and several Boas. It also houses a great array of turtles (including an Alligator Snapper) and several Poison Dart Frogs. Best of all, you and your kids can pick up and handle (under supervision) various, non-venomous reptiles. Here’s a shot of Twin B holding a local native snake, the Iforgottowritedownae whateveritsnamewasii. (I would like all readers to note how fabulously cool it is that my daughter has absolutely zero fear of snakes. Her gemelo wouldn’t touch it.)

Another interesting- but unnerving- thing we saw at the reptile zoo was this Boa feeding on a live rat. I couldn’t bring myself to take a video (seemed just a bit too ghoulish) but you can get the idea from these 2 shots (left and below, right). Whole process took about ~8-10 minutes.

Up in Monteverde we encountered a number of other Creepy-Crawlies. One piece of advice I have for anyone visiting the cloud forest is to bring along a small flashlight. When you pass a trailside embankment, it’ll often be riddled with small holes, and the light will allow you to peek inside. Holes without webs are the most promising, as it means it’s regularly used by some critter entering/exiting.

More Spiders!

Here’s an Orange-Kneed Tarantula, (genus = Brachypelma, unclear on species), we found in one such hole. It’s a female, waiting out the day in (relative) safety before emerging to hunt at night. (I mentioned the monster-sized Costa Rican Tarantula Hawk Wasp I spotted later that day in this post.) This is a common tarantula up around Monetverde, and it’s a looker, with a Halloween-ish orange & black color pattern and a leg span of up to 8”.

There are 900 species of Tarantula in the world. Here in Utah the one we get is Aphonopelma iodius. I’ve spotted them while biking or hiking probably about a dozen times since I’ve lived here, always between July and October. October is most common, when you’ll see them crossing roads, but I’ve also seen them on the Shoreline trail just before dawn in the Summer months. (This photo was taken in late October along Shoreline behind the U. of Utah Hospital.) When you see a Tarantula walking about in October, it’s almost always a male. In general when it comes to Tarantulas, males roam, females park.

Tarantulas sure look scary, but they’re pretty harmless to humans, with a bite not much worse than a bee sting. And despite what you saw on the Brady Bunch, I’ve never encountered, or even heard of anyone finding, a Tarantula in their hotel room, much less their bed. But they’re a lot scarier to some smaller mammals; Orange-Kneed Tarantulas hunt (among other things) mice. When they catch one they paralyze it with a venomous bite, then inject it with digestive juices that liquefy the mouse’s insides. Over the next several days they’ll suck the mouse dry, leaving behind an empty sack of fur and bones.

Scorpions!

But here’s a Creepy-Crawly you are likely to find in your Costa Rican hotel room. I like to say that no Central American vacation is complete till you find a Scorpion in the bathroom, and I’ve encountered them in hotel bathrooms in both Costa Rica and Belize. Here’s the one I found in our Santa Elena Hotel (and promptly dispatched with a deodorant stick.) There are over 2,000 scorpion species in the world, found on every continent except Antarctica. 7 of them are native to CR. I believe this one is a Bark Scorpion, probably Centuroides margaritatus (or possibly C. limbatus.) Though the sting of either species is apparently extremely painful, neither appears to be as dangerous as the Arizona Bark Scorpion, Centruroides sculpturatus, which, before antivenin became widely available, killed a few hundred people a year in Mexico.

Scorpions are fascinating and ancient; they’ve been around for something like 400 million years. They’re common here in Utah (we have 9 species), and so I’ll return to them in a future post. But fascinating as Costa Rican Creepy-Crawlies are, this post has run on long enough, so I’ll wrap up with this photo of an unknown Centipede Bird Whisperer spotted in Monteverde. And remember, when vacationing in the Neotropics, shake out your shoes in the morning.

Side Note: Missing from this post of course is are the Vampire Bats and Bullet Ant we saw, which I’ve already blogged about in this post and this post ,respectively. I also, regrettably and in the interest of time, had to omit over several other wonderful Creepy-Crawlies we encountered, including Leaf-Cutter Ants, Frogs and Toads, a tree with poisonous bark (Manzanillo) and the Biggest Moth Ever (pic right.)

That’s 4 posts I’ve done on our Costa Rica trip. Seriously, do I get my money’s worth out of a neotropical vacation or what?