Are Roadrunners Really Real?

As a father, I believe it is my duty to see to my son’s education. So I’ve been exposing him to the classics. Specifically, Looney Tunes cartoons. I was flabbergasted when one of his friends stated he didn’t know who Bugs Bunny was. I mean, what is this world coming to?

So we’re sitting on the couch, eating popcorn and watching the Coyote blow himself up, and flatten himself, and fall off things in his endless quest to catch the Roadrunner. Dynamite and shotguns and anvils to the face. Good, clean family fun. Right? Right. And while we’re watching, my son asks the question. “Are roadrunners really real?”

“Well, yeah,” I tell him. “They live in the southwest.”

On the screen, the Roadrunner beep-beeps, and sticks his tongue out, and leaves the Coyote eating his dust.

“Are they that fast?” my son asks.

“I doubt it,” I reply. “But, let’s find out.”

 

He doesn’t think roadrunners are real?

It’s a sensible position, if you think about it. We weren’t watching Wild Kratts or Dinosaur Train or some other sort of educational program. We’re watching cartoons about coyotes getting 100,000 pound weights dropped on them. He’s seen coyotes on TV and at the zoo, so he can trust they’re real. But beeping birds that can outrun trucks? Yeah, he’s got a right to be skeptical.

Point taken. So tell us about roadrunners.

Sure. This is a roadrunner:

Specifically, that is Geococcyx californianus, also known as the Greater Roadrunner, a member of the cuckoo family (or, technically, a member of the Cuculidae family which includes roadrunners, cuckoos, and some other birds). As you can see, they don’t look much like the Roadrunner from the cartoons. They’re also a whole lot smaller than a coyote – coyotes in the American desert southwest range 15 to 25 pounds and get about 4 feet long, while the Greater Roadrunner gets up to 2 feet long and weighs up to 1 1/2 pounds. They’re also not blue and purple. They’re a mottled brown and white that blends in with the scrubland and desert they (mostly) inhabit – they can be found as far east as the Mississippi River, but you mostly find them in the southwestern United States and northern Mexico. Also, unlike the cartoon Roadrunner, they don’t beep. Instead, they make a sound that’d I’d describe as sounding like “wut-wut-wut-wut“.

The cartoons show the Roadrunner stopping to eat piles of birdseed, as part of the Coyote’s traps. If Wiley E. Coyote was hunting a real Greater Roadrunner, he’d be better off with a heap of bugs. Roadunners are primarily carnivorous, eating insects, spiders, scorpions, mice, other birds, lizards, and snakes (even rattlesnakes). They hunt by running up to their prey, grabbing it in their beak, and slamming it repeatedly against the ground until it stops refusing to be eaten. His trap might work on the Lesser Roadrunner (Geococcyx velox), though – they eat seeds. They als also roadkill, so they’d be attracted to the results of the Coyote’s inevitable failure (which could explain why it seems as if the Roadrunner keeps coming back to gloat…).

How fast is a roadrunner?

Fast. They’re fast.

Roadrunners can fly, keep this in mind. They’re just not much good at it. They’ll fly to get up to their nests, when sprinting downhill, and to escape from predators, but they can’t maintain altitude for more than about a minute. They’re much better adapted to running, and can hit speeds in excess of 20 miles per hour – an impressive feat for a tiny bird – fast enough to catch dragonflies and hummingbirds on the wing. They’re even fast enough to prey on rattlesnakes, one of the few animals that can.

That’s pretty fast. Could the Coyote catch one?

The answer to that is a solid “maybe”, because it turns out that coyotes are fast. They’ve been seen to sprint at up to 45 miles per hour, and can run at up to 20 mph over distances of a mile or two. That speed drops to about 10 mph if they’re running over longer distances. I couldn’t find any details on how long a roadrunner can maintain its 20+ mph running speed, but the videos I’ve watched don’t show them slowing down for much of anything. So, like so many things in nature, it comes down to circumstances. In a flat-out race, Coyote would finally be dining on Roadrunner. But the roadrunner would be bobbing and weaving and trying to dodge until the exhausted coyote couldn’t keep sprinting, and then (assuming it isn’t lodged in the coyote’s jaws) keep running.

Huh. Anything else?

Yeah. There’s one cartoon in which, in an effort to catch the Roadrunner, the Coyote dons a “female roadrunner costume”. The Roadrunner is unimpressed, running up with a sign that reads “No thanks, I’ve already got a date,” before beeping and sprinting off. This, it turns out, is actually fairly accurate. Well, except for the crosdressing coyote. See, roadrunners are monogamous. The mated couple breeds in the sring, lays anywhere from 2 to 12 eggs, and take turns incubating the eggs. It’s not all happy domesticity, though. The fledglings will crowd out any late-hatching runts, which are then generally eaten by the parents.

Also, along with pooping and peeing all at once, roadrunners have an extra adaptation to help conserve water. They excrete waste salt through their tear ducts, as a way of conserving water. As a result, they almost never need to drink – all of the fluids they need come from their prey.

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What Are Cataracts?

This question came up because my son’s babysitter is fostering a blind dog – an adorable little black poodle with milky white eyes named Rosie.

Seriously. How cute is that?

My son and his babysitter’s two children love her and spoil her and carry her around, and they describe her as having “moon eyes” because they sort of look like full moons. The Peppermint Pig Animal Rescue was going to get her eyes operated on to remove the cataracts, but it turns out she also has detached retinas. So the surgery wouldn’t really change anything for her.

We were talking about the dog, and the news, and my son asked “what are cataracts?” Because we’d used the word and he didn’t know it.

“It’s what makes Rosie’s eyes white,” my wife replied.

“But what are they?” he replied.

“It’s…” My wife thought for a second. ‘It’s like a film on her eyes, that she can’t see through.”

“But why are they called that?” my son persisted.

So. What are cataracts?

This. This is a cataract.

I’ll be honest, here. I don’t actually know. My wife’s explanation seemed as good as any, and I think I always sort of assumed that they were something like scar tissue. But, like with so many other things, I’ve never really stopped to ask what they were or what causes them. So, since my son asked, it’s time to change that.

Definition

Merriam-Webster, my go to for dictionaries thanks to a handy app, gives two definitions for “cataract“:

  1. [Middle English, from Medieval French or Medieval Latin; Medieval French catharacte, from Medieval Latin cataracta, from Latin, portcullis] : a clouding of the lens of the eye or of its surrounding transparent membrane that obstructs the passage of light
  2. a obsolete : waterspout
    b : waterfall; especially : a large one over a precipice
    c : steep rapids in a river the cataracts of the Nile
    d : downpour, flood cataracts of rain cataracts of information

I’m guessing that the medical term is used explicitly because of the “portcullis” meaning in Latin, since cataracts more or less block light from entering the eye. The Online Etymology Dictionary seems to agree, so that makes me feel better.

The medical condition

Multiple online sources (the Mayo Clinic and the American Academy of Ophthalmology to name just two) agree with the Merriam-Webster definition. Cataracts are a clouding of the lens of the eye. This can result in blurry vision, seeing double, light sensitivity, having trouble seeing well at night, needing more light when reading, seeing “halos” around lights, and seeing bright colors as faded or yellowed. They are the most common form of vision loss in people over the age of 40, and the single most common cause of blindness in the world (in the US alone, more than 22 million people have cataracts).

Aging is the most common cause of cataracts, because the proteins in the lens of your eye will denature over time. This is not a good thing, because your lens is made of living cells and denatured proteins disrupt the cells and can even kill them. Diabetes and high blood pressure can accelerate the process, as can ultraviolet light (UVB, specifically) and other radiation and blunt trauma to the eye. There is a genetic component to the development of cataracts as well, particularly if someone develops them in childhood or as young adults. These aren’t the only causes, of course. Just the most common.

The most common forms of cataracts are subcapsular, nuclear, and cortical. Subcapsular cataracts start at the back of the lens, and are most common in diabetics and people taking medical steroids. Nuclear cataracts start in the center of the lens, and are most commonly associated with aging. Cortical cataracts start at the edge of the lens and work inwards ina “spoke-like fashion”. There are also congenital cataracts, which you are born with or develop during childhood – usually due to your genes or some form of infection or trauma.

Treatment

Ultimately, the only treatment for cataracts is to remove the existing lens and replace it with an artificial lens called an intraocular lens that matches the prescription (if any) that you need for your glasses. The intraocular lenses come in a wide variety of different types, and if you need one you should consult with your ophthalmologist to see which ones make the most sense for you.

Surgery is generally considered a last resort, though. As long as the cataract symptoms aren’t bothering you, and the problems with your vision can be corrected with glasses, there generally no need to undergo surgery. Cataract surgery is considered pretty routine, but the only really risk-free surgery is one that you don’t have.

Hang on, hang on. This is all about people. Didn’t this start with a dog?

Yep. But cataracts aren’t limited to humans. It’s a condition caused by disruption and damage to the lens of the eye, so any animal with an eye with lenses can develop cataracts. There’s a lot of information on the internet about dog cataracts, and mentions of cats. One veterinarian stated that they are “the most common cause of blindness in dogs, and can also affect people or any species of animal”. Like humans, animal cataracts can develop from age, diabetes, trauma, genetics, or something called Progressive Retinal Atrophy – the name for a cluster of generic disorders that cause the retina to degenerate. Animal cataracts can be treated in the same way as human cataracts. Progressive Retinal Atrophy has no treatment, though.

Impaired vision and even blindness aren’t a death sentence for a house pet, though. Rosie gets around just fine, as long as you don’t move her food and water dishes and rearrange the furniture a whole lot. So if you live in the Cincinnati area and want to adopt an adorable little blind dog (or another animal), contact the Peppermint Pig Animal Rescue. They’ve got a lot of animals looking for a loving new home.

What Fossils Did I Find?

Way back in February, I wrote about the fossils my son found. At that time, I promised him I’d do some research and find out what kind of fossils they were. To recap, here’s what they looked like:

Time passed, and he asked other questions, and I got busy studying for a certification test at work (which is why I’ve been so quiet the past few months). But finally, since I’ve had a chance to catch my breath, it’s time to answer a question: what, exactly, are those fossils?

Well?

My primary source for this is Identification Guide for Common Fossils of the Cincinnatian. Based on this guide, most of the fossils appear to be Brachiopods, most likely some species of Cincinnetina (since they’re common in the region) – from the pictures in the guide, though, they could be Platystrophia ponderosa. The point is, they’re certainly brachiopods, and they’re around 480 to 440 million years old.

To tell you the truth, my son was disappointed that he didn’t find a Tyrannosaurus Rex.  That wouldn’t be particularly likely, however, for a few reasons.  The first being that T. Rex didn’t live 440 million years ago, and the second being that if T. Rex did live 440 million years ago in Cincinnati he would have drowned.  Because Cincinnati was under water.

Map courtesy of The Paleomap Project

So, no Tyrannosaurs here.  Certainly not in the strata that was laid down on his brachiopods.

And what, exactly, is a brachiopod?

Well, Wikipedia says that brachiopods are:

…a group of lophotrochozoan animals that have hard “valves” (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the front can be opened for feeding or closed for protection.

“Lophotrochozoan” animals are a clade of bilaterally symmetrical animals with cillia around their middle, if that helps.

Brachiopods are related to mollusks and annelid worms (earthworms and leeches). There are around 330 living species. There were a whole lot more of them back in the past, with the greatest diversity of Brachiopods occurring in the Devonian. The Permo-Triassic mass extinction crushed a lot of that diversity, and it has never fully recovered.

Modern brachiopods feed by sucking water in through their sides, using their cilia to trap particles of food, and then expelling the water and any waste products through the front. They absorb oxygen through their skin, and have colorless blood, and some modern species can live over 30 years (assuming they aren’t eaten).

Case closed, right?

Well, except for this strange little thing:

Uhm. What is that?

I have no idea. I’m pretty sure that’s not a brachiopod. Not unless we’ve got the shell end-on, and it also folded in a pretty dramatic fashion. After some digging, I four possible candidates. Here they are.

1. It’s just a rock. Needless to say, I find that boring. It is the null hypothesis, but I don’t think it’s accurate. after all, the color resembles that of the other fossils in the piece of stone my son found. So, although it’s certainly possible, I don’t think it’s correct.

2. It’s a piece of an Isorophus cincinnatiensis. This might be a reach, because it would make it a fragment of an arm of a 440 million year old echinoderm. Pros for the argument are that it’s from the region, it’s about the right size, and it looks kind of like the arm seen in this picture. Cons for the argument include the fact that it doesn’t look a whole lot like the arm in that picture.

3. It’s a bit of coral. I couldn’t find any pictures of coral that curves like that, but that doesn’t mean they don’t exist.

4. It’s something I can’t identify. Yes, yes, that’s an utterly lame hypothesis. But I’ve got nothing else, and I’m pretty sure it’s some flavor of fossil. So, I’ll probably just leave it at that. Unless someone reading this happens to know what that might be.

Why Do Birds Poop And Pee At The Same Time?

I don’t know if my son was watching a nature program, or if he’d been talking about this at school, or what. All I know is that, as we were walking into the condo one day, he suddenly stops and points. “Look dad! An owl!”

I stare along the side of the building, wondering which of the trees he’s talking about. Or is it perched on a balcony, maybe? “I… don’t see it,” I say.

“It’s right there!” he exclaims, pointing. “Oh, no. It’s a squirrel. Look, dad! A squirrel!”

“I don’t see it,” I tell him. “But my eyes aren’t as good as yours.”

He nods at that. “Dad?”

“Yes, son?”

“Why do birds poop and pee at the same time?”

…that is not what I thought he was going to ask.

Do they poop and pee at the same time?

This seems like the first place to start, because I’m not at all certain they do. I mean, sure. I’ve heard this before. But it wouldn’t be the first time I’ve found that “received wisdom” is wrong and that something I thought was true wasn’t true. However, in this case, it seems that received wisdom is correct.

This is going to be more than I wanted to know, isn’t it?

Hey, you’re the one reading this.

Pretty much all animals produce ammonia (NH3) during digestion. It’s a side effect of the breakdown of proteins, which all animals need whether they’re carnivores or herbivores. Ammonia is, however, toxic (doses of 350 mg/kg of weight can kill), which means that animals have to deal with it in some fashion. And by “deal with” I mean “get rid of”.

Generally speaking, mammals will mix it with some of the waste carbon dioxide (CO2) they produce through breathing and convert it into urea (CO(NH3)2) – a far less toxic chemical (the lethal dose is 8,471 mg/kg) that also happens to be water soluble. Mammals then, generally speaking, expel it (along with other waste chemicals) in the form of urine.

Birds don’t do this. Birds, it seems, don’t even have bladders.

Sigh. Tell me more.

To start with, most birds convert ammonia into uric acid (C5H4N3O3, lethal dose around 5040 mg/kg) instead of urea. The other thing they do, which is the reason why they simultaneously poop and pee, has to do with anatomy. See, bird excretory systems work a lot like lizards. They have kidneys, of course, and ureters (the ducts that allow urine to leave the kidney). However, they lack bladders. Instead, they have something called a cloaca – a multipurpose organ that serves as both the reproductive and excretory organ.

The urine enters the cloaca through the ureters, where it is pushed up into the large intestine. The large intestine re-absorbs much of the water content, allowing the urine to be concentrated into a thick paste before it is passed by the bird. since uric acid dries white, this lends bird droppings their distinctive appearances.

So, in short, birds poop and pee at the same time because of evolution.  And because they aren’t equipped to poop and pee separately.

Why Do Sharks Eat So Many People?

“Dad?” my son asked as we got out of the car. “Why do sharks eat so many people?”

I assume he’d seen something about sharks at school, but the question still came out of nowhere. Thirty seconds before, he’d been telling me about his school’s Mardi Gras party and asking me if I felt better (because I’ve been sick, which is why this article still isn’t looking at the fossils he found). So, I put my mind to it. “I don’t think they do,” I answer.

“They don’t eat people?” he responds, sounding skeptical.

“Well, they can,” I concede. “But they don’t eat people all that often.”

“Why not?” he asks, and I swear he sounds disappointed.

“Well, a lot of them are kind of small. And we aren’t the kind of things they normally hunt.” I’m trying to remember shark facts, now. “Most of them are probably just wondering what we are, and people get scared of them and think they’re attacking.”

“Why do people get scared?” he asks.

I shrug. “Why did you get scared of them, when we went to the aquariam?”

“Because they look mean!” Then he grabs my hand. “Since you’re not feeling good, can we take a break and play Star Wars?”

Do sharks eat a lot of people?

This is one of those questions where I really hope I told my son the right thing, because I was working from half-remembered articles I’d read years ago, and memory is a fickle, tricky thing. Fortunately, it turns out that the University of Florida maintains the International Shark Attack File (ISAF), which they describe as “the longest running database on shark attacks, has a long-term scientifically documented database containing information on all known shark attacks, and is the only globally-comprehensive, scientific shark attack database in the world”.

Before we dive into the numbers, though, it’ll be important to define two terms the ISAF uses: provoked attacks and unprovoked attacks.

  • An unprovoked attack is edfined as “incidents where an attack on a live human occurs in the shark’s natural habitat with no human provocation of the shark.”
  • A provoked attack, on the other hand, usually occurs “when a human initiates physical contact with a shark, e.g. a diver bitten after grabbing a shark, attacks on spearfishers and those feeding sharks, bites occurring while unhooking or removing a shark from a fishing net, etc.”

The ISAF reports that 2016 was a pretty typical year, with a total of 150 alleged shark attacks. Out of those 150 attacks, here’s how the results broke out:

  • 81 were classified as unprovoked attacks (53 total in the United States, 43 of which were in Hawaii).
  • 37 were classified as provoked attacks.
  • 12 were sharks biting boats (aka “boat attacks”).
  • 1 was a shark eating part of an already dead human cadaver.
  • 12 had insufficient evidence to prove a shark attack.
  • 7 were determined to be attacks by other marine animals (including a barracuda and an eel).
  • 5 were determined to be abiotic injuries (that is, an environmental injury – scraping coral or rock, for instance).

So, in the fairly typical year of 2016, there were 118 total shark attacks on humans (131 if you count the boat attacks and the scavenging). 2015, by contract, hit 98 unprovoked shark attacks- the highest yearly total on record. On average, shark attacks result in 6 to 8 fatalities per year (depending on what period of time you average out), but 2016 only had 4 shark attack fatalities. Statistically, surfers are most likely to be attacked 958% of the total), followed by recreational swimmers and waders (32.1% of the attacks).

That’s not a lot of attacks, is it?

No, not really. In fact, there’s a whole lot of animals that are much more likely to kill you. According to the BBC, venomous snakes kill an estimated 50,000 people each year, rabid dogs kill an average 25,000 people each year, crocodiles kill an estimated 1,000 humans per year, and hippos kills an estimated 500 people per year. All of which makes the paltry 6-8 shark kills each year pretty tame.

friendly-shark

Still, it’s probably best not to do this unless you know what you’re doing.

The ISAF provides some other interesting comparisons. The odds of dying from a shark attack are 1 in 3,748,067. Fireworks are about 11 times more lethal (odds of death: 1 in 340,733), sun and heat exposure are 273 times more lethal (odds of death: 1 in 13,729), and the flu is 59,664 times more likely to kill you (odds of death: 1 in 63).

Why do shark attacks get so much attention, then?

Rarity, in my opinion. Rarity and shock/

See, we notice things that appear out of the ordinary. According to the CDC, heart disease is the leading cause of death in the United States (614,348 deaths in 2014), followed by chronic lower respiratory diseases (147,101 deaths), accidents (136,053 deaths), stroke (133,103 deaths), Alzheimer’s disease (93,541 deaths), diabetes (76,488 deaths), and influenza and pneumonia (55,227 deaths). Most of those get no attention at all, unless they’re really spectacular or they happen to someone famous. But death by animal attack? That’s unusual, particularly in the United States. And particularly because we like to think we’re outside the food chain. Homo sapiens sapiens is, realistically, the ultimate alpha predator and one of the dominant environmental forces on the planet. It’s unsettling to be reminded that we’re still animals, and that we can still become prey.

Also, sharks inhabit an alien environment that we can only meaningfully visit with the benefit of technology. A wolf or bear attack happens on dry land, so the surroundings aren’t inherently hostile to us. But sharks? A shark could kill us with their own environment, even if the bite isn’t fatal. So, they seem frightening.

Just in case I am one of the unlucky ones, any tips?

Actually, yes. Here’s what the ISAF says: “If one is attacked by a shark, we advise a proactive response. Hitting a shark on the nose, ideally with an inanimate object, usually results in the shark temporarily curtailing its attack. One should try to get out of the water at this time. If this is not possible, repeated blows to the snout may offer a temporary reprieve, but the result is likely to become increasingly less effective. If a shark actually bites, we suggest clawing at its eyes and gill openings, two sensitive areas. One should not act passively if under attack as sharks respect size and power. “

How Many Spiders?

I’ve been sick for a few days now, so I haven’t put any real time into the “what are these fossils” article I promised last time. Instead, let’s look at something comparatively simple. I picked up my son from Kindergarten yesterday. Normally, since I was home and it’s only about a quarter mile, we’d have walked. But, like I said, I’ve been sick. So he’s in the back seat excitedly telling me about his Valentine’s Day party. “Dad?” he asks as we pull into our garage.

“Yes, son?” I respond.

“How many spiders can you carry?”

No, I have no idea where that came from. But I’ve gotten used to that by now. “Well,” I say, “that depends on how big they are, and how cooperative they are.”

So, how many could you carry?

“I could carry a hundred spiders!” he declares.

“Maybe,” I tell him. “If you could put them in a box. Or if they were tiny and well-trained.”

So, how many could you carry? Like I said, it depends on the spider. The good people at Guinness World Records say the Patu marplesi is the smallest spider, while Wikipedia contradicts them and states that a related species – the Patu digua is the smallest. Either way, it’s a tiny spider – the body size is only 0.37 mm – and the author of Catalog of Organisms states that “If one of these spiders crawled into your ear while you were sleeping, it could probably slip into your Eustachian tubes and tap on the back of your eyeballs.” So try not to think too hard about that.

patu-digua

“Peek-a-boo!”

I couldn’t find anything at all about how much (little?) this critter weighs. So, I’m going to run the risk of estimating. Here’s what I did, so that you can play the home game. I found an article titled “Estimating Live Spider Weight Using Preserved Specimens” from The Journal of Arachnology in 1996. It provides a formula for calculating weight from length for spiders: ln weight = 1.844 + 2.711(ln length), and seems to indicate that the weight is read in milligrams (mg) and the length in millimeters (mm). So, that would give us ln weight = -1.844 + 2.711(ln 0.37). That works out to… let’s see…

  1. ln weight = -1.844 + 2.711(ln 0.37)
  2. ln weight = -1.844 + -2.695
  3. ln weight = -4.539
  4. e^ln weight = e^-4.539
  5. weight = 0.010684 mg

So, one 0.37 mm spider appears to weigh 0.01 mg. How many of these could we move? Let’s find out?

Bare Hands

My palm is, roughly speaking, a 9 cm by 9 cm (90 mm by 90 mm) square. That gives me 8,100 mm of surface area, so I could stack a single layer of 8,100/0.37 = 21,891 well behaved Patu digua on one hand. Using both hands, I could carry 43,782 of them. The two-hand load would come out to 0.43782 grams, or 0.0015 ounces of spider.

Let’s try and do more. If I cup my hands, I get a sort of rounded cone that’s 7 cm (70 mm) in diameter by 7 cm (70 mm) deep. That gives me a volume of 359,189 cubic mm. Now, let’s assume that the Patu digua takes up the same volume as a sphere 0.37 mm in diameter. That’s 0.212175 cubic mm. So, in my cupped hands, I could carry 359,189/0.212175 = 1,692,890 Patu digua. Those guys would weigh in at 18.0868 grams (0.63799 ounces).

We’re not savages, you know

Yes, I know. So let’s fill a box. A standard U-Haul shipping box is 41.5″ (1054.1 mm) x 38.5″ (977.9 mm) x 18.75″ (476.25), for a volume of 429,072,327.3375 cubic mm. That means I could carry 429,072,327.3375/0.212175 = 202,256,756 of the little spiders – 21.606 kg (47.6 pounds) of Patu digua. My son weighs more than that, so I know for a fact that I could easily carry that box of spiders from my house to my car, and then from the car to the Post Office, and then from the Post Office back to my car because the USPS would most likely refuse to accept that package.

Cool. What about big spiders?

National Geographic informs me that the South African Goliath Birdeater Tarantula is the biggest spider in the world as measured by body size. Nothing I could find gave me an explicit size, but terms like “puppy sized” and “the size of a dinner plate” were bandied about with distressing familiarity. National Geographic also states that:

Many of the locals in northeastern South America regard T. blondi as a tasty snack. They first singe off the urticating hairs, then wrap the spider in banana leaves to roast it. Tarantula expert Rick West, who once sat down for a meal of these spiders with the local Piaroa people of Amazonas in Venezuela, says T. blondi can be surprisingly tasty and moist. (Also see “UN Urges Eating Insects; 8 Popular Bugs to Try.”)

“The white muscle ‘meat’ tastes like smoky prawns, while the gooey abdominal contents is hard-boiled in a rolled leaf and tastes gritty and bitter,” West says. “The three-quarter-inch [two-centimeter] fangs are used after the meal as toothpicks to remove T. blondi exocuticle from between one’s teeth.”

goliath

“I’m tasty!”

On the other hand, if you’re measuring by legspan the prize goes to the giant huntsman spider, with a leg span over one foot (30.48 cm) across. No word on how they taste, though.

huntsman

“Come on and have a go, if you think you’re hard enough!”

Without specifics, I can’t tell you how many I could handle. One per hand, maybe, and maybe four in a shipping crate. But, on the other hand?  Oh my god no.

What Is A Fossil?

A couple of days ago the weather was nice enough that I walked to my son’s kindergarten to pick him up. As we walked home, he declared that he was “collecting nature” and picked stuff up. Pine cones (which he rejected after a minute as being “squishy”) and sticks, things like that. Oh, and a rock. He picked up a largish, flat rock that got him asking if we could eat off a stone one day. “People used to do that,” he assured me. “Can we?”

“Maybe,” I told him, turning the stone over in my hands. He’d asked me to carry it, so he could climb a retaining wall. “But we’ll have to clean it well first.” Then something caught my eye. “Hey, look,” I said. “Fossils!”


His eyes went big, and he scrambled over to see what I was talking about. Impressions of shells in the stone. “My first fossil!” he declared, taking the stone back. “I found my first fossil!” And suddenly, he had to carry the stone, and he told me he wanted to get a paint brush out.

“Why?” I asked, puzzled.

“That’s what paleontologists use to clean stones!” he told me.

At the end, we settled on using an old toothbrush of his to scrub the dirt away. And that is how we found the thing that will be at least two entries for this blog.

What is a fossil?

If you’re reading a blog like this, you probably have a passing familiarity with what a fossil is. If nothing else, you’ll be thinking about dinosaur bones that have turned to stone and then been dug up and assembled to display in a museum. A fairly succinct definition of the word comes from Biology Online, which states:

noun, plural: fossils

(1) Any preserved evidence of life from a past geological age, such as the impressions and remains of organisms embedded in stratified rocks.

(2) The mineralized remains of an animal or plant.

adjective

Having the characteristic, or pertaining to the nature, of a fossil.

Supplement

Fossils include shells, imprints, burrows, coprolites and organically-produced chemicals. The oldest fossils were bacteria that existed 3.8 billion years old. Fossils are once thought of to be all from extinct species until some were found to belong to species that are still living.

Word origin: from Latin fossilus, (something dug up)

In other words, fossils aren’t just bones, and they aren’t even necessarily pieces of living things. The Sam Noble Museum in Oklahoma follows what appears to be a common practice of breaking fossils into three broad categories: body fossils, molds and casts, and trace fossils.

  • Body Fossils are what you usually think of when you think of a fossil, the fossilized remains of an organism (or part of an organism). Usually, it’s just the bones or other hard parts of the animal because the soft tissues rot and/or get eaten.
  • Molds and casts are a type of body fossil, but they aren’t directly the remains of the organism. A mold is rock that has formed around the body fossil, making an imprint of the fossil’s shape. A cast is what you get if new rock forms in that mold, or more commonly if sand or mud fills the inside of a hollow structure (such as a shell) and becomes rock. Interestingly, sometimes you get molds of the soft tissues of the dead animal. When found, these allow insight into what the animal’s skin was like.
  • Trace fossils are indirect signs of a creature, such as footprints or coprolites (fossilized waste) or burrows or nests.

How Do Fossils Form?

I’ll be honest, and tell you right here and now that I’d assumed that there was a whopping one single way that fossils form. The classic “bones get covered and minerals slowly leach into them over time, replacing the calcium in the bone” routine you probably learned about in elementary school (or, if you’re like me, from reading a ton of dinosaur books in kindergarten). This is certainly one way to do it, but it isn’t the only way. The most common methods are petrification and carbonization, but there are most certainly others.

Petrification is the most common variety of fossilization, and (as you might guess) it’s the classic “bone or shell to stone” form of fossilization. It comes in at least two forms, replacement and permineralization.
replacemnet-fossil-galleryimage

  • Replacement is the best known of the best known methods, because it’s the one you always hear about. Water dissolves the original hard structures, replacing them with different mineral matter. What kind of mineral matter depends on the mineral content of the water, but calcite, silica, pyrite, and hematite are most common.
  • Permineralization happens when ground water infiltrates microscopic pores and cavities in the hard structure, depositing minerals. This results in a fossil that still has much of the original hard material left behind, mingled with the deposited mineral.

Carbonization is a form of fossilization most commonly found in plants, although animal can do it as well. Under the right conditions the organic substances of the organism decay but the carbon in the organic molecules is left behind in the shape of the fossilized structure.
carbonized-fossil

There’s also a few types of fossil that you might not think of as “fossils”, because they don’t turn to stone. Plants and animals trapped in amber are fossils, for instance. So are the animals that got trapped in tar pits (La Brea being the famous example here in the United States), and the animals that froze and then freeze-dried in the Arctic (such as mammoths). They’re still preserved evidence of life, even though they didn’t turn to stone.

So, that’s a really high level look at fossils. Tune in next time, when we try to work out what fossils he has. Because trust me, my son has been asking.