Infinite Apples!

MONKEYS have TAILS...so what are these guys?

Seasonal Habitat Change

If we rewind geological time regressively
And I could say the same for this hibiscus tree
And this lizard and this flea and this sesame seed
And if you still disbelieve in what your senses perceive
Then I could even use this rhyme as a remedy
‘Cause there’s so much variation in the styles in this industry
And differential survival when the people listening
Decide what they’re into and what really isn’t interesting
You could thrive like Timberlake on a Timberland beat
Or go extinct like Vanilla Ice and N’Sync
It’s survival of the fittest, but fitness is a tricky thing
It changes from place to place and from winter to spring

Baba Brinkman, Rap Guide to Evolution, "Natural Selection"

NOTE: Some adult lyrics in this rap

http://music.bababrinkman.com/track/natural-selection-20

Birds of a Feather: Coloration, Evolution, and A Question

Lots of bird stuff in the news and on my mind lately. Among the biggest stories, a new study that helps show how birds evolved from non-avian dinosaurs.

The most comprehensive family tree of meat-eating dinosaurs ever created is enabling scientists to discover key details of how birds evolved from them.

The study, published in the journal Current Biology, shows that the familiar anatomical features of birds – such as feathers, wings and wishbones – all first evolved piecemeal in their dinosaur ancestors over tens of millions of years.

However, once a fully functioning bird body shape was complete, an evolutionary explosion began, causing a rapid increase in the rate at which birds evolved. This led eventually to the thousands of avian species that we know today.

A team of researchers examined the evolutionary links between ancient birds and their closest dinosaur relatives by analyzing the anatomical make-up of more than 850 body features in 150 extinct species, then using statistical techniques to analyze their findings and assemble a detailed family tree.

Based on their findings from fossil records, researchers say the emergence of birds some 150 million years ago was a gradual process, as some dinosaurs became more bird-like over time. This makes it very difficult to draw a dividing line on the family tree between dinosaurs and birds. [NOTE: This is the language of the press release related to this study, but because birds are dinosaurs, I wish they would have found a better way of expressing this. I suppose it's no different, though, than when people talk about humans and primates as if humans were not primates--which we of course are!]

Findings from the study support a controversial theory proposed in the 1940s that the emergence of [significantly] new body shapes in groups of species could result in a surge in their evolution.

The initial process is so gradual, said one researcher, that if you traveled back in time to the Jurassic, "you’d find that the earliest birds looked indistinguishable from many other dinosaurs.”

aAnother researcher added: “There was no moment in time when a dinosaur became a bird, and there is no single missing link between them. What we think of as the classic bird skeleton was pieced together gradually over tens of millions of years. Once it came together fully, it unlocked great evolutionary potential that allowed birds to evolve at a super-charged rate.”

And here's an interesting finding.

Peacocks gave Charles Darwin fits. He wrote to a friend that every time he saw one, he felt sick. Why? Their tails seemed to represent a real problem for his theory of evolution by natural selection. Of what survival use could a tail, however beautiful, be when it made its owner clumsy and slow? Eventually a "just so story" (a sort of fairy tale invented by Rudyard Kipling that pretends to explain why something is the way it is--like bears have no tails beause they tried to use them to ice fish and they froze off and their babies were born without them...that sort of thing) was concocted to try to reconcile the ornate pain-in-butt tail with the animal's need to fly away from predators fast.

It goes like this: Besides natural selection, there's such a thing as sexual selection. One partner, usually the female, has control over who she mates with, and she seeks the boys with th most desireable traits to be the dad to her babies. The biggest, the fastest, the healthiest, the most handsome. Whatever. Think of any trait and some animal somewhere will go "hubba hubba" over it.

In the case of peacocks, it was assumed that sexual selection occurred because if a male of the species ("peafowl" if you include the males and females) was able to survive with that heavy and ridiculous hing stuck to its butt, he must be strong and sassy. The peahens got a look at a big fancy tail like that and something in their tiny brains went, "He must be some special kind of bird to have all that weight strapped to his backside and still be able to get away from foxes. So I'd like that one there to be daddy to my babies, who will then get some of that super mojo in their genes."

Sounds plausible, yeah? Enough to let Darwin get some Zzzzzzs at night. Nothing like a pretty story to explain away an sticky problem. But as Thomas Huxley said, “Science is organized common sense where many a beautiful theory was killed by an ugly fact.”

And that's just what happened recently. Check out this edited news item:

A scientist took it upon himself to fill in the missing data points. He used high-speed digital video cameras to capture the take-offs of five peacocks with their tails; the experiment was then repeated after clipping off the birds’ tails with pruning shears. The peacocks would be induced to fly from a lower perch to a higher one by an experimenter clapping or rattling a stick at them. Filming the peacocks from different angles showed the birds’ rate of climb and acceleration—things that matter if you’re pursued by a predator—as they launched from their perches.

So, how much did dragging around a giant tail slow down the peacocks? Actually, not that much. According to the research, "a tiny amount."

Overall, the new find refines our understanding of sexual selection as it applies to the peacock, but it doesn’t shake the foundations of the larger evolutionary model.

“Organisms will go to extravagant lengths to produce structures and behaviors that take a lot of effort,” one researcher said. “However, if they win mates, apparently they are worthwhile to the organisms. If the organisms died overwhelmingly as a result of such effort, then maybe we’d have to rethink the phenomenon.”

Our final bird-related story has to do with flamingos, the pinkish wading birds that often stand in the water on one leg (for reasons not fully understood). Why is the flamingo pink? Can you think of a just-so story on that one? "Because it likes to soak in warm Strawberry Crush." "Because it's always a little embarrassed by it's skinny legs and big beak." Nope. And while the reason flamingos are pink might not be fully understood, the chemical they use to make that pink color is.


Flamingos need beta carotene to create that deep pink color. They get it from tiny shrimp that live in the water they eat from. Most zoos don't provide diets that are as rich in beta carotene as the birds eat in the wild, so they never develop such a deep shade of pink. They are light--from whitish to a much paler pink. Flamingos,then, are an excellent example of how the presence or absence of some ingredient in the environment has a profound impact on appearance that is not genetic.

By the way, beta carotene is a source of Vitamin A, which humans (and other animals) need for night vision, healing, and several other important functions. Do you know what's a great source of beta carotene? Its name is right there.

That's right: Carrots.

Final thought, related to the flamingo get its color from its diet. I was at the Como Zoo, in the tropics exhibit, and there was a tiny, brightly colored arrow dart frog--just walking around on the rocks! Not in a container of any kind, running free! I admit, I was a little freaked. These frogs are notorious for being very toxic. Some, I had heard, were even used to poison spear tips. I saw a docent (one of the volunteer educators) nearby and told him,"One of your poisonous frogs got out!" And he reminded me of something I should have rememebered on my own. These frogs do not produce their own toxins. This is from an online article about these frogs:

Poison frogs derive their toxins from the spiders, beetles, ants, centipedes, termites and other insects that make up their diet.

Because the frogs roaming free (intentionally--none had escaped) did not have access to the foods that would make them toxic, they were as safe as a Minnesota peeper.

Archer Fish Superstar

I go to the Como Zoo & Conservatory (http://www.comozooconservatory.org) every Sunday morning that I have free. There is always something new to see. For example, I had always hoped to see the archerfish, housed in a tank in the marine house (with the penguins and puffins and seahorses!), use their amazing shooting ability to hunt for bugs.

And one morning a few Sundays back, I got my wish. The zoo staff member feeding the fish was placing grasshoppers (I think) on the rocks a couple of feet higher than the fish in the tank, and the fish were “spitting” jets of water at them, knocking them into the water to eat. It was spectacular. And the family near me watching the spectacle was not sure that they were really seeing what they were seeing. “What’s going on?! Are they jumping up so fast we can’t even see them?!”

It’s one of those awkward moments, right? You know something, but you don’t want to look smart-alecky. But I was so excited I couldn’t contain myself, and I explained a little about how these fish hunt, how they have special eyes, brains, and mouths that allow them to do this amazing thing. And then I sort of caught myself and said, “Sorry to go off there…these are just some of my favorite animals.” Fortunately, the mom said, “No, no…I’m really glad you did! That is fascinating.”

So it’s not always a bad thing to show off a little of what you learn, outside the classroom, I guess.

Coincidentally, a study just a week or two later in the Cell Press journal Current Biology on September 4 said that archerfish are even more skilled than had been realized. Using water as they do includes them in the fairly exclusive club of tool-using animals (although that club seems to grow every year, doesn’t it?). What makes it tool use—and not JUST tool use, but SKILLFUL tool use—is the way the fish change the hydrodynamic properties of the jet of water from their mouths.

One of the scientists who conducted the archerfish research said that this high level of accuracy probably evolved because where the fish are located, “there is very little to actually shoot at, so it’s important for the fish to be efficient.”

Paper authors Schuster and Gerullis trained some archerfish to hit targets from 20 to 60 centimeters from a specific location, and measured the water jet variables produced. This led to the discovery that archerfish are able to adjust the jet, in ways that compare with how human throw projectiles at targets. Schuster said that this ability requires “precise time control of movement.”

The scientists speculated that what they have learned about water jet control from the fish might find application for human products, including in medicine.

Archerfish, because of their unique hunting adaptation, have sometimes been used as an example of an organism that could not have evolved by Darwinian means. The number of “moving parts”—in the mouth, brain, and eyes—needed to produce such an amazing adaptation really is dizzying. In that way it reminds me of the mimic octopus, which has such a near-perfect ability to imitate its surroundings, camouflaging itself into almost any background by means of color, pattern, and even texture, that it seems more like magic than biology.

How great for science that such challenging puzzles abound! Using the tools of science in the natural world, what discoveries might we make in our efforts to answer such puzzles that contribute to our understanding of the natural world, and maybe make our lives better? Anyone who had the mad skillz of a mimic octopus or an archerfish would be a superhero to rival Mystique or Hawkeye.

Beautiful Bugs

I recently started reading a great new book on insect evolution, Planet of the Bugs: Evolution and the Rise of Insects, by Scott Richard Shaw. It's highly readable for smart sixth graders on up, and is filled with fascinating information presented in a friendly, conversational tone.

Below I quote from a few of the facts I've learned so far in Bugs:

...Keep in mind that given the current rates of new discoveries, description, and publication, it could take an estimated 500 more years just to provide names and morphological descriptions for the remaining insect species.

Insects are cold-blooded animals, and since blood flows through the veins in the their wings, insect wings work very well as little solar panels for warming up on cold mornings.

Small size has promoted insect species diversity by allowing bugs to divide the world into exceedingly small niches.

For as long as 150 million years, insects were the only animals that could fly, and that gave them great advantages in terms of their ability to escape predators and to disperse and colonize new areas.

Over the past 120 million years, insects have coevolved and explosively diversified in tandem with the angiosperms--the dominant forms of plant diversity in modern ecosystems. They are essential as pollinators and seed-dispersers for most of the flowering plants, whose communities would be vastly diminished if all plant-associated insects were eliminated.

Trees of Life

Monarch Life Cycle

I get ridiculously excited about going to the State Fair every year, starting in about April. I’m not sure why. I can’t remember ever having a real “peak experience” there, and once I had my camera and equipment stolen from me while standing in line for cheese curds. But I can’t help it. I love the fair.

And one of the things I love most, although not as much as cheese curds, is the Butterfly House on the northwest corner of Dan Patch Avenue and Underwood Street. You can walk into this classroom-sized screen-porch like room that’s just all aflutter with gorgeous butterflies. You have to be very careful, because butterflies are very delicate, but if you spend a few minutes and just stand quietly, they will flit around you, nestle near you, and sometimes land on you. Amazing.

Connected to the butterfly viewing area is a sort of gift shop that sells, among other things, pairs of live monarch caterpillars just getting ready to go into their chrysalis stage (more on that below). They come in a plastic screen-topped container about the size of a regular peanut butter jar, and they have a few fresh (but rapidly wilting!) milkweed leaves to munch. I had never bought them before, but this year I did. Ten bucks for two—I got them just before getting on the bus to go home, because I didn’t want to drag the poor little guys with me around the fair all day long first.

When I told the guy at the counter that I wanted to buy the caterpillars, he asked how “ready” I wanted them to be.

“Ready?”

“Yeah, like how soon do you want them to go into their chrysalises?”

I hadn’t thought about this, but sooner seemed better than later—less could go wrong, I thought. So I said, “Oh, really ready.” He picked up a container with a pair he said “should be good to go this afternoon.”




And in fact, I barely got them home before they were clinging to the top of the container (see the photos) and trying to stick a strand of their strong silk to the ceiling to hang by. By evening, they had “become the letter J,” as I’d been told they would. And by morning, they were full-on cocooned critters, hermitically sealed and vacuum packed for fresh flavor. Not really…but they were in there pretty good.

Beside the sparkling fresh chrysalis hung the dried-out exoskeletons of the caterpillars, like crusty old (full-body) socks that had been slipped off and discarded.

Except that one poor little guy had trouble with his cable, which broke and allowed it to fall to the leaf-covered bottom below. I didn’t know what to do about that, so my instinct was to do nothing. This proved to be a bad instinct, probably, because in a couple of days that chrysalis had grown blackish and I figured the developing butterfly inside had died. I wasn’t sure the reason for this, but considered that maybe the position of the caterpillar’s body was crucial to the various cells knowing where to go as the butterfly developed. In developmental biology, up-down/left-right cues are vital to the various cells—heart, skin, wings, legs, eyes, etc.—getting to the right spot and forming properly. Had falling on its side disrupted the information needed for the caterpillars “inner engineer” to make those decisions? I don’t know. I’ll look into it sometime.

Even though I lost one chrysalis, the other one seemed healthy and I thought I saw some very slight changes over the course of several days. At least I had no reason to think the caterpillar was NOT becoming a butterfly in there!

One morning a few weeks ago I looked in on the chrysalis and saw a dramatic change—the colors and patterns of a monarch were clear through the chrysalis, pressed against the interior wall!

After work that day I came home to find that the butterfly had emerged, and not too long ago. It was still a little moist and soft from being inside the chrysalis. I was glad that it had not been trapped in the too-small container like this the entire day, because I think that might have restrained its wing development, cramping them from spreading out properly.

I took the container with the butterfly in it outside, near the lawn behind my apartment complex where some young neighbors were playing soccer. Many of my neighbors are Mexican-American, and seem to love soccer the way I as a kid loved American football. When they saw what I had in my hands, they stopped their game and came over to watch. They asked a few questions, about where I had gotten it, what had happened to the other one (I had left the blackened chrysalis in the container), what I was going to do with it, and so forth.

We looked at the empty shell of the chrysalis, still stuck to the containers inside top cover.

We watched the butterfly take its first few flaps together. It looked like it was trying to get used to its new body, and we could almost sense how strange it might be to have wings for the first time. After a few minutes, I took the new butterfly to an open field nearby and left it to complete its preparations for flight on its own, because it seemed to me that with all of us watching, it was perhaps acting shy.


In the days since I released my little butterfly friend, I’ve done some reading and Internet research on the lifecycle of the monarch butterfly. It’s truly fascinating and a little strange. I outline the key events below.

Four By Four: The Complicated, Convoluted Life Cycle of the Monarch Butterfly

Four generations, with four stages each, per year. The stages are egg, caterpillar, chrysalis, and butterfly. The generations are a little more complicated.

In early spring—one source I consulted said February, but that couldn’t be for Minnesota, at least not in the winter of 2014—hibernating monarchs emerge from their long chilly nap and find a mate. Ah, romance is in the air, carried on regal stain-glassed orange wings! Once fertilized, the eggs are deposited on milkweed leaves, and hatch into tiny caterpillars in around 5 days.

Do you know the kids’ book, The Hungry, Hungry Caterpillar? That’s these guys. Sporting the B&W fashion sense of a penguin or zebra (they’re bodies are white, ringed in black lines--but to be fair, many sport lemon or lime colored accents), they do nothing but chomp. Milkweed for breakfast, milkweed for lunch, milkweed for after-milkweed snacks, milkweed for dinner. Short break; more milkweed. This plant, which gets its name from the sticky milk-looking juices that ooze out of any tear of cut in their stems and leaves, helps to fatten up the caterpillars. And it does something else. It makes them taste super bitter, so that birds avoid them. (There is a very tricky butterfly that is actually delicious [I hear], but looks so much like a monarch that birds avoid it, too, not wanting to risk a mouthful of yuck. More on that another time).

A couple of weeks of this constant chowing down at the all-you-can-eat milkweed buffet, and our little friends are fat enough and old enough for Step 2: The Chrysalis.

This is a most amazing structure. Attached to the underbelly of a milkweed leaf by a tough, semi-flexible bungee cord, the chrysalis dangles, its thin, leathery surface initially hiding the incredible changes happening inside.

Until the last day or so. Then the transformation becomes visible through the translucent shell and the spots and veins and colors of wings are clear, pressed against, the inside, eager to burst forth into a very different, less gravity-bound world. This happens about a week to 10 days after the caterpillar produces the chrysalis.

The hatching is awkward and looks uncomfortable. There is no single “ta-da” moment, no instant revelation of a brand-new outfit, on and fully functional. No. The wings must unfold, and they must be pumped up, and they must dry and solidify, stiffening in preparation for flight. What would it feel like for a sausage to become a kite? Of course an insect has no such strong sense of itself, is not conscious as we would be of this metamorphosis, but it is hard not to project ourselves into an imagined monarch mind, and fantasize about what that would be like—going to bed a worm and waking up an angel.
And now the monarch that had been an egg, a caterpillar, and a chrysalis-dwelling changeling will become ready to lay eggs of its own, to produce the next of the four generations.

This second generation will hatch in May or June in Minnesota, go through the same process outlined above, and then produce the third generation, which will go through that process yet another time, and bring us to the fourth generation, which is different than its predecessors. It will be a butterfly in September or October, but it will not die after six weeks as the previous generations. Instead, this generation of monarchs will migrate, flying to California, or Mexico, where it will live for six months before starting this whole process all over again.

I wish that when I was talking to my young Mexican-American friends I would have thought to discuss with them the long flight our new hatchling might have ahead of it, possibly toward the land of their ancestors. I can only hope that some of them might have seen this wonderful article in the local Spanish-language publication, Vida Y Sabor:

http://issuu.com/lcnmedia/docs/vidaysabor-529/5?e=1298139/9115554

Bones

Putting the Fun Back in Fungus

Como Zoo: The Giraffe's Adaptations

The giraffe has some highly unusual and specific adaptations, among which at least one that demonstrates how evolution must work with the "materials at hand" rather than being able to come up with more elegant engineering solutions. Richard Dawkins explains one such compromise in the following video.

https://www.youtube.com/watch?v=cO1a1Ek-HD0

A word about Dr. Dawkins. He has had some controversial things to say on subject matter that technically lies outside of science. Feel free to agree or disagree with his opinions on non-scientific topics. But when it comes to evolutionary biology, Dawkins is in fact a leading light (his brilliant book "The Selfish Gene" is seminal), and he is not expressing opinion but explaining biological facts.

One fact about giraffes--again, something that points toward common descent--that is surprising is that they have the same number of vertebrae in their necks as humans and most other mammals. You can see from the photo of the model giraffe that one reason for that is that the bones are elongated. Human cervical (roughly, "neck") vertebrae are short, compact, and closely nested. You can see that this is not the case with giraffe cervical vertebrae. Again, this is typical of what evolutionary processes must do--make do with materials at hand. It might have been an advantage to have more, smaller bones in terms of flexibility (and in fact, in snakes this adaptation DID occur), but just because an organism might benefit from some feature does not mean it will get it. Novel features are largely determined, initially, by chance,and those differences that confer a survival and reproductive advantage spread throughout the species population. Over geological time (thousands of years), advantageous features accumulate, bringing about usually gradual (rarely, less gradual) change.

Other adaptations that enable the giraffe's unique body plan include those related to the circulatory system. Consider the problem--getting an adequate blood supply all the way up that long neck into the brain, and, if the giraffe, say, has to bend down to get a drink, the pressure can't, oh...make its little noggin explode? So the giraffe has evolved some unusual hydraulic equipment, which top-notch science writer Natalie Angier explains in the October 7 2014 New York Times:

Also of interest is the giraffe’s exceptional cardiovascular system. A large giraffe can stand 20 feet tall — the height of a second-story window — with its neck accounting for roughly a third its span and its long legs the same. The multitiered challenge, then, is how to both pump blood very high and retrieve it from far below while avoiding burst capillaries in the brain or blood pooling around the hooves.

As part of the Danish Cardiovascular Giraffe Research Program, scores of scientists have traveled to South Africa to study giraffe physiology. They have measured blood pressure at different sites and found readings that range from high to ridiculous — up to five times human blood pressure — yet with none of the organ damage commonly seen in hypertensive patients.

Instead, the giraffe has extremely thick blood vessel walls to prevent blood from leaking into surrounding tissue, while rugged, inflexible collagen fibers in its neck and legs help keep the blood traffic moving, rather as the tight antigravity suits worn by astronauts and fighter pilots will maintain blood flow under the most extreme gravitational shifts. A complex mesh of capillaries and valves store and release blood in the neck, allowing the giraffe to bend over for a drink of water and then raise its head again quickly without fainting; when the giraffe is standing still, sphincters at the top of the legs limit circulation to the lower extremities, to minimize the risk of fluid buildup around the hooves.

Researchers were also surprised to find that contrary to old textbook wisdom, giraffes do not have unusually large hearts for animals their size. “It’s half a percent of body mass, and that’s the same as we see in a cow, dog or mouse,” said Christian Aalkjaer of the department of biomedicine at Aarhus University in Denmark.

Moreover, Dr. Aalkjaer and his colleagues have determined that the giraffe’s cardiac output — the amount of blood pumped into circulation each minute — is modest, proportionally lower than it is in humans. That finding could help explain why giraffes rarely run for very long: Their hearts can’t deliver oxygen to their muscles fast enough to power extended aerobic exertion.

Lizard Island Observation Game Helps Kids "Think Like a Scientist"

I confess that I have no played this game myself yet--I'm not much of a gamer--but I'm looking forward to trying this out. From what I read and understand, it seems like a fun tool to aid biology understanding. This is what an article ( http://www.gamepolitics.com/2014/08/20/lizard-island-observation-teaches-children-think-scientists) says about the game:

Lizard Island Observation sends players on an adventure to search micro islands for brown anole lizards. Players must find, catch, tag, and measure each one they find. Along the way, players can tap on various island life to learn more about it. All of these facts, questions, and answers are recorded in a field notebook.

The game is also tailored for use with non-readers or children with learning disabilities because it offers the option to have the text read aloud. The game is recommended for children in grades K-5. A school version of the game will also have lesson plans and assessment tools for teachers and homeschoolers.

The game is available here, on iOS and Android, for $4.99: www.buddingbiologist.com

Fossil Sites Within A Day's Drive

http://www.mycountyparks.com/county/Floyd/Park/Fossil-Prairie-Park-Preserve-and-Center.aspx

http://ashfall.unl.edu/

http://www.smithsonianmag.com/evotourism/evolution-world-tour-ashfall-fossil-beds-nebraska-6171451/

I first learned about Ashfall Fossil Beds State Historical Park in Royal Nebraska, from an article in Smithsonian’s magazine called Evolution World Tour, in the section titled: “ Ashfall Fossil Beds, Nebraska,” which said:

Prehistoric rhinoceroses and horses died of volcanic ash inhalation 12 million years ago – their fossils are studied now as a perfect example of natural selection.

I confess I had no real idea how far Royal Nebraska is from Minneapolis where I live, so I used Google Map and discovered it’s about six and half, seven hours, depending on the route. I selected a route through Sioux Falls, South Dakota, because I figured me and my partner would want to stay overnight someplace with decent but not terribly expensive hotels, and I was curious to see the Great Plains Zoo in Sioux Falls.

The drive in my then-new Kia Rio (jealous much?) was…I’m going to say “serene” here. It’s not fair to call it boring, because it has a real beauty to it, but it’s not a dramatic beauty like pounding surf; it’s a quiet, static kind of beauty. Lush rolling hills, sheets of cornfield extending to the horizon, sky sky and geez there’s more sky. But this is not an unpleasant drive, and the right MP3 player music mix really helps.

About the Great Plains Zoo (http://www.greatzoo.org): This is not a bad zoo by any means, but for those of us who have grown accustomed now to the more animal-friendly habitats at the Minnesota Zoo, and the increasingly better habitats at Como Zoo, it seems comparatively stark and unintentionally mean-spirited. There are rhinos there, and that was a big part of the draw for me. I was really interested in seeing a live African one on the same trip as I saw its distant Nebraska cousin’s fossilized bones. Circle of life? Something.

But the paddock for the rhinos was rather small and while the animals were in no way mistreated or neglected, I couldn’t help feeling a wave of the same sort of sadness that used to overtake me at Como Zoo, seeing, say, the polar bear in an enclosure not much larger than my apartment. Como has moved to correct much of that last-century cruelty; I hope all zoos are able to find the resources to follow suit.

Oh. And the MAIN reason for going to this zoo was their alleged axolotl. It’s a marine salamander, extinct in the wild, and from only one small region of Mexico. A real freak show, this salamander—it reaches sexual maturity while still a “tadpole,” so it keeps its frilly lion’s mane of gills and lives an entirely aquatic life. It’s an example of what’s called “neotany,” and some scientists have speculated that humans might also, in their evolutionary history, have benefited from some neotany, because baby chimpanzees and bonobos look “more human” than the adults of those species do.

At any rate. Axolotl. All kinds of cool. Nowhere to be found, despite it’s having appeared on their website of animals to see. We asked around and they no longer have an axolotl, which at the time disappointed me quite a bit. But I fixed that by getting my own this spring. Her name is Rose (Axol Rose) and she’s doing great. Take that, Great Plains Zoo!

The actual Ashfall park is in a remote-but-easy-to-find location, set among rolling hills mostly covered in cornfields. It’s nice, new, and modern, with a newish interpretive center that does a great job of explaining, for example, the evolution of horses represented at the site. And the main attraction is a huge barn- or hangar-like structure that shelteringly covers the actual site. The site is an active dig, and you can observe paleontologists carefully digging among the amazing riot of shapes.
Mike Voorhies, the paleontologist who made this discovery with his wife Jan back in the 1970s, was onsite, still digging and answering questions. I can’t promise that everyone will be so lucky as to have the actual number one expert on Ashfall present to, with great generosity, respond to a series of questions, but if it happened to us, maybe it’s not SO unusual.
A long way to come just to see a graveyard? I suppose the case could be made. But I thought it was awesome, and like in some great myth for me the bones seemed to come alive and I could imagine the rhinos and camels and horses and other animals alive in that very different time when Nebraska—NEBRASKA!—looked more like the African plains.

The OTHER fossil site possibly worth driving to is still a fair distance, but only about a third as far as Ashfall: Fossil Prairie in Rockford, Iowa. It’s approximately two and half hours from Minneapolis, in the northeast corner of Iowa. I took advantage on the trip of seeing and staying at the Frank Lloyd Wright hotel in nearby Mason City, but other more modest accommodations are also available in the area if you plan to make an overnighter out of the trip.

The thing about the fossil center (fossilcenter.com) is NOT that it is site to spectacular specimens like in Ashfall, but that they are abundant, easy to find, and available for collection. These are fossils from the Devonian, all marine animals, so you won’t find any dinosaurs or mammoths or anything, but there is-for me, at least—a special thrill that comes from finding shells and coral and other animals that have been dead for almost half a billion years. I went the morning after a very heavy thunderstorm, and the torrents of rain washed the soil and sand away from some areas, leaving behind a number of exposed fossil shells. I described it as “beachcombing the Devonian,” and I found it thrilling.

Trips are sometimes complicated to arrange, and seldom entirely convenient. They can cost money, and they for sure cost time—some of it being pretty bored. All I can say is, if you plan right and are open to it, these mega-field trips are totally worth the effort for the budding paleontologist and her parents or friends.
Final note: I stopped somewhere along the way, on my drive down to the Fossil Center, that I will have much more to say about in a later post, but wanted to put here as a further enticement to make the trip. At about the one-third mark or so, in Owatonna, Minnesota, is the Reptile & Amphibian Discovery (RAD) Zoo, and it’s well-worth the stop as long as you’re buzzing nearby. As I said, more on that later, but take a peek:

http://www.theradzoo.com/

Plants

Squiggle finally learns what "tardigrades" (or "waterbears") actually are:

"Tardigrade!" shouted Ollie.

"What now?" asked Squiggle, a little startled by the way a loud, unfamiliar word had shattered the silence of a lazy Sunday afternoon.

"That's the word of that thing that one of Mr. Li's students is doing something on for her science fair project...look, there's a book on tardigrades on his desktop, on the short pile."


Kids & Teachers TARDIGRADE Science Project Book: How to Find Tardigrades and Observe Them through a Microscope by Michael Shaw (you can find it here at Amazon.com: http://www.amazon.com/Kids-Teachers-TARDIGRADE-Science-Project-ebook/dp/B009D7VHXK/ref=sr_1_1?s=books&ie=UTF8&qid=1407356021&sr=1-1&keywords=tardigrade).

Squiggle excitedly hopped off the bookshelf--well, hopped as only a small, not very thin and not very coordinated worm can hop--and shimmied on up to the computer's keyboard. She had to know what these "tardigrade" critters were, what they looked like, and why the fuss. She did a search and came up with this site:



http://tvblogs.nationalgeographic.com/2014/03/19/5-reasons-why-the-tardigrade-is-natures-toughest-animal/

And after that, she even found a plushy doll version of the so-homely-cute waterbears:

http://www.giantmicrobes.com/us/products/waterbear.html

Humane Society One Good Place to See Variety Within Species

Visiting a Humane Society shelter can be a sad affair, and one that can make animal-lovers angry. See that tiny dog in the photo? Its owner gave it up for "lack of space." LACK OF SPACE?! That little guy could have lived in a shoebox!


Having said that, animal shelters (and adoption days that pet stores sometimes sponsor) are great places to see the incredible amount of variety that exists within one species of organism. Charles Darwin, writing in "On the Origin of Species," used dogs as an example of this sort of variation:

But let us look to the familiar case of the breeds of dogs: it cannot be doubted that young pointers (I have myself seen striking instances) will sometimes point and even back other dogs the very first time that they are taken out; retrieving is certainly in some degree inherited by retrievers; and a tendency to run round, instead of at, a flock of sheep, by shepherd-dogs. I cannot see that these actions, performed without experience by the young, and in nearly the same manner by each individual, performed with eager delight by each breed, and without the end being known--for the young pointer can no more know that he points to aid his master, than the white butterfly knows why she lays her eggs on the leaf of the cabbage--I cannot see that these actions differ essentially from true instincts. If we were to behold one kind of wolf, when young and without any training, as soon as it scented its prey, stand motionless like a statue, and then slowly crawl forward with a peculiar gait; and another kind of wolf rushing round, instead of at, a herd of deer, and driving them to a distant point, we should assuredly call these actions instinctive. Domestic instincts, as they may be called, are certainly far less fixed than natural instincts; but they have been acted on by far less rigorous selection, and have been transmitted for an incomparably shorter period, under less fixed conditions of life.

How strongly these domestic instincts, habits, and dispositions are inherited, and how curiously they become mingled, is well shown when different breeds of dogs are crossed. Thus it is known that a cross with a bull-dog has affected for many generations the courage and obstinacy of greyhounds; and a cross with a greyhound has given to a whole family of shepherd-dogs a tendency to hunt hares. These domestic instincts, when thus tested by crossing, resemble natural instincts, which in a like manner become curiously blended together, and for a long period exhibit traces of the instincts of either parent: for example, Le Roy describes a dog, whose great-grandfather was a wolf, and this dog showed a trace of its wild parentage only in one way, by not coming in a straight line to his master, when called.

So consider visiting a pound, shelter, or adoption day and observing, drawing, describing or photographing the differences among breeds (and crosses!), to help fulfill this standard:

1. Structure and Function in Living Systems
1. Living things are diverse with many different observable characteristics.

The following short video clip from HHMI helps tell the story very well:

http://www.hhmi.org/biointeractive/dog-breeding