Archive

Archive for April, 2010

Supersize Me: Supervolcanoes

Perspective

The sides of the cauldron are steep, thickly covered by ancient volcanic gravel. Around the rim of the massive crater, winds can gust to as much as fifty miles an hour. The panorama from the volcano’s rim is of the seared, scorched Death Valley. Downwards, the slope plummets over five hundred feet to the bottom. There is a trail, but running through the gravel is more fun. Walking it, you have to go sideways to keep your feet. Running, the key is to move in short diagonal bursts, to use the gravel to brake yourself. Don’t start falling, you won’t stop until you hit the bottom, and the gravel is sharp.

This is Ubehebe Crater, Death Valley, California. Open to the general public, there are now long lines of people trudging up and down the switchback trail. But when I first remember being there, some fifteen years ago, only a few people did more than look over the rim. Very few went all the way to the white-silt bottom. My family did climb down into the crater. Ubehebe is a small, extinct volcano, but even so, it terrified me. Those early adventures triggered a fascination with volcanic phenomena that has lasted ever since.

Mythology

Volcanoes are one of the most potent, powerful forces on the Earth. They have crept, over the ages, into our nightmares, our folklore, our speech. Intricate mythologies formed around them. Hephaestus, Pele, Llao, Mafuei, Aetna and Fuji all shook the earth and spewed fire in their rages and passions.

Some mountains have their own mythology, too, becoming gods or forces with their own life, malevolence and force. Even now, villagers pray to Mount Etna for her mercy.

Others were the entrances to Hell, the burial grounds of the gods, or the birthplace of monsters. Often, they were the sites of great battles, most likely because of the great earthquakes that often accompany their eruptions.

Read the rest of this entry »

Perception, Neurology, and Fiction

“Curiouser and curiouser!” cried Alice, (she was so surprised that she quite forgot how to speak good English,) “now I’m opening out like the largest telescope that ever was! Goodbye, feet!” (for when she looked down at her feet, they seemed almost out of sight, they were getting so far off,) “oh, my poor little feet, I wonder who will put on your shoes and stockings for you now, dears? I’m sure I can’t! I shall be a great deal too far off to bother myself about you: you must manage the best way you can—but I must be kind to them,” thought Alice, “or perhaps they won’t walk the way I want to go! Let me see: I’ll give them a new pair of boots every Christmas.”
~ Alice’s Adventures in Wonderland by Lewis Carroll

Over the past century and a half or so since the original publication of Alice’s Adventures in Wonderland, a number of scientists, doctors, and literature lovers have speculated as to what the real-world sources of the fantastic elements of Lewis Carroll’s story were.  One interesting suggestion is that Carroll suffered from the altered perception of body size that is sometimes associated with migraines, and this was the inspiration for Alice’s potion-induced shrinking and growing when she first tumbles down the rabbit hole.

While it turns out that the speculation about Carroll is probably incorrect (pdf), the complexity of the human brain leaves it vulnerable to neurological disorders and illusions that alter the perception of the world such that it doesn’t accurately reflect reality. While that can be distressing and debilitating to the person who is afflicted, such alterations can be an excellent inspiration for speculative fiction. What sets SF apart from non-genre fiction is that it often depicts what we would normally consider a delusion as an accurate reflection of reality.

Read the rest of this entry »

Worldbuilding with real worlds

Lieutenant Elena Jones shivered with excitement as her Ecological Survey craft entered the atmosphere. She checked the readings in front of her carefully. This was her first solo mission, and she was determined to do everything just right. She came in over the major planetary ocean, following the prevailing winds. She stared out the window at the coast, her first sight of land not filtered by cameras and instruments. Her planet, hers! Not just her first sight of this Earthlike world, but the first sight ever. Elena guided the little survey shuttle over the high coastal mountain range, and leveled the craft out over the lush green tropical forest beyond.

Hold on, something’s wrong. Did you spot it? (Besides the cliches; we’re here for the science.) The worldbuilding here jams the components of a planet together randomly instead of fitting each piece into its proper ecological spot. A tropical forest doesn’t go downwind of the coastal mountains on an Earthlike planet. Major categories of vegetation and their associated animal life, called biomes, can only be found in particular places. At a global scale, the locations of desert, grassland, forest and tundra biomes are determined by temperature and precipitation. At a particular site other factors like soils and disturbance come into play, but let’s stick to whole planets for now.

If you draw a graph with temperature as one axis and precipitation as the other, each kind of biome can be added as a region.

Tundra is very cold and dry. Deserts are dry and can be warm or cold. Grasslands are dryish and warmish. Tropical rainforests are warm and wet. That’s pretty straightforward, but how are the different types distributed on a planet? Deserts and grasslands and rainforests all belong somewhere, but why?

Read the rest of this entry »

None of these things is just like the others

In my previous post, I explored convergent evolution: when two different species, usually separated by distance, evolve a similar physical characteristic independently of each other. At the end of the post, I said that I would follow up with a post on the far more common divergent evolution.

Simply put, divergent evolution is when two groups of the same species evolve differently. The environments in which the groups live are the most common cause of divergent evolution – in other words, if two groups of the same species are separated into different environments, they will each evolve and adapt separately to fit the environment they’re in. Arguably the most famous example of divergent evolution is Darwin’s finches, which he described in On the Origin of Species:

“The inhabitants of the Cape de Verde Islands are related to those of Africa, like those of the Galapagos to America. I believe this grand fact can receive no sort of explanation on the ordinary view of independent creation; whereas on the view here maintained, it is obvious that the Galapagos Islands would be likely to receive colonists, whether by occasional means of transport or by formerly continuous land, from America; and the Cape de Verde Islands from Africa; and that such colonists would be liable to modification;—the principle of inheritance still betraying their original birthplace.”

- On the Origin of Species, Chapter XII: Geographical Distribution. Charles Darwin, 1859

The “inhabitants” Darwin refers to in the above passage are the variations of finches. (It’s interesting to note that, since Darwin was developing the very concept of evolution, he didn’t have a word for it to utilize – instead referring to it as “modification”.)

Read the rest of this entry »

You Only Find What You’re Looking For

Author’s Note: This is the first SiMF post picked up for reprinting by io9 — I know it will be the first of many!

Extraterrestrial life is a staple of SF and the focus of astrobiology and SETI.  Yet whereas SF has populated countless worlds with varying success, from Tiptree’s haunting Flenni (Your Haploid Heart) to Lucas’ annoying Ewoks, real ETs remain stubbornly elusive: nobody has received a transmission demanding more Chuck Berry, and the data from the planetary probes are maddeningly inconclusive.  Equally controversial are the shadowy forms on Martian asteroid ALH84001, although the pendulum has swung toward cautious favoring of the biological possibility after scientists discovered nanobacteria on earth and water on Mars.

In part, we’re hobbled by the limits of our technology, including the problems of sample contamination and method-specific artifacts.  But we’re also severely limited by having a single life sample.  Despite its dizzying variations in form and function, extant terrestrial life arose from one source.  We know this because our genetic blueprint and its associated molecular machinery are identical across the three domains (archaea, eubacteria, eukarya).  So to be able to determine if something is alive, we need to decide what is universal and what is parochial.  We stumble through redefinitions each time our paradigms shift or our techniques achieve higher resolution.  Worse yet, our practices lag considerably behind our theories.

Read the rest of this entry »

A Hidden Spark: Piezoelectrics

From Wikipedia:

Piezoelectricity is the ability of some materials (notably crystals and certain ceramics, including bone) to generate an electric field or electric potential in response to applied mechanical stress. The effect is closely related to a change of polarization density within the material’s volume. If the material is not short-circuited, the applied stress induces a voltage across the material. The word is derived from the Greek piezo or piezein, which means to squeeze or press.

The first recorded, modern study of piezoelectrics took place in the 18th century. Carl Linnaeus and Franz Aepinus started with research of the pyroelectric effect, using various materials to generate an electric response due to temperature change. This research prompted Rene Just Hauy and Antoine Cesar Becquerel to posit a relation between mechanical stress and electric charges. Unfortunately, their experiments proved inconclusive, leading to a bit of a gap in experimentation.

Read the rest of this entry »

Augmented Reality Maps and the Crime Wave of the Future

Augmented Reality is one of the scifi promises I’ve been anticipating with equal amounts of dread and desire. Now that AR is real, I find that disgust and attraction are the least of my emotional feedback to the fledgling technology. Since beholding this splendid monstrosity, I feel responsible for it.

But what is it? Wikipedia says, “Augmented reality (AR) is a term for a live direct or indirect view of a physical real-world environment whose elements are augmented by virtual computer-generated imagery.” Blaise Aguera y Arcas’s 2010 TED Talk includes an amusing demonstration. Augmented Reality places layers of primarily visual information between people and the real world. Put generously, it’s a tool and a toy that allows us to interact with our environment in ways we’ve literally only been able to imagine before now. Cynically, it’s a spambot’s wet dream and a nightmare for privacy lovers everywhere.

Read the rest of this entry »

Extending Medical Nanotech

A couple weeks ago, Calvin Johnson wrote an interesting post on nanotechnology, discussing some of the proposals, current research, and ways to write about it in a more realistic manner. One application he didn’t touch on, however, was the current work being done in nanomedicine.

Most current medical nanotech takes the form of either microscopic drug vectors tuned to open for certain wavelengths of light, or particles designed to identify cancers by infiltrating cells or locking onto certain proteins. These particles are largely organic and often designed to mimic the actions of antibodies. All these methods are being touted as ways to combat not only cancer and infections, but have also been used to repair tissue damage following heart transplants.
Read the rest of this entry »

Form Equals Form Equals Function

Why is it that the most enduring, recognized form for aliens to take in our stories is “humanoid”? Walking upright, two legs, two arms, two eyes, etc. The most stereotypical term to refer to visiting aliens is “little green men“. Why do we so often assume that aliens will be so similar to us?

Part of it is undoubtedly because there is a comfort in familiarity; if they look kind of like us, they must be like us, right? (Conversely, we feel more confident when the bad, violent aliens look nothing like us.) A certain lack of imagination on the part of those who craft the stories also plays a role. And let’s not discount the practicality of putting a human actor in a roughly human-shaped costume.

But there’s actually a reasonable scientific justification for an alien life form to have a similar form to ours. It’s called convergent evolution.
Read the rest of this entry »