Archive for March, 2011

Thursday: “It was made to be impossible. But you needn’t give up on that account.” Robin McKinley. Context?

From Beauty, a 1978 retelling of the fairy tale, Beauty and the Beast. Beauty is overhearing the invisible servants talking.

Friday: “Everything in life is unusual until you get accustomed to it.” L.Frank Baum. Context?

From Ozma of Oz. The Scarecrow has just met the Woggle-Bug, who has commented on the whole party (the Scarecrow, the Tin Woodman, Jack Pumpkinhead, the Sawhorse and Tip) being rather unusual.

Saturday: “No man can be fully efficient if he expects praise or appreciation for what he does.” Murray Leinster. Context? 

Part of the Manual of the Interstellar Medical Service, quoted in “The Grandfathers’ War.” I have the story in Doctor to the Stars; it has been reprinted with others about Calhoun and his tourmal, Murgatroyd, in Med Ship, which is still in print.

Sunday: “Then I’ll tell the truth. We’re allowed to do that, in emergencies.” Card. Context? 

From Ender’s Game. Colonel Graff is talking with others of the monitoring team just before recruiting Ender to the Battle School.

Monday: “Hope was an addiction.” David Brin. Context? 

From The Postman. This is fairly early in Gordon’s story, but still sixteen years after a catastrophe had almost wiped out civilization.

Tuesday: “I knew I had to learn his secret, but I couldn’t just ask him or he’d know I didn’t know.” Zelazny. Context? 

From Nine Princes in Amber. Corwin is traveling to Amber with his brother Random. But he has no idea of what Random is doing, beyond the fact that it’s seriously weird, and he doesn’t want Random to find out he’s amnesiac.

Wednesday: “I learned to Heal my own injuries just so I could stay alive.” Bowling. Context?

From Homecoming. Roi is explaining to Marna how he learned to Heal.

This post has been updated with photographs.

All genes for white markings produce a wide range of amounts of white. The leopard (Appaloosa) gene produces not only a wide array of amounts of white, but also of patterns. Unlike other spotting patterns, it is often progressive with age.

Because the patterns produced by the leopard gene vary so much, I will spend more than one week on them. This week, I will focus on breaking the patterns down into components, following Sponenberg, and commenting on their distribution and genetics.

In the United States, the leopard gene and the patterns it produces tend to be associated with specific breeds, notably the Appaloosa and Pony of the Americas breeds. The Colorado Ranger and the mustang often exhibit the leopard complex colors, as well.

Worldwide, however, the leopard complex patterns are very widely distributed throughout Europe and Asia as well as the Americas. Further, most breeds which have any of these patterns have all of them—a further indication that a single gene is necessary. The only exception at the current time is that a second gene locus, Pattern-1, may be needed to produce the full leopard pattern. A number of other modifiers probably exist, but they are not known. None of these modifiers, however, seems able to do anything without the presence of at least one Leopard allele.

Genetically, the Leopard allele is one of two possible alleles (the other is wild-type) at the Transient Receptor Potential Cation Channel, Subfamily M, Member 1 locus, thankfully abbreviated to TRPM1. This locus is on equine chromosome 1. Leopard is incompletely dominant over wild-type.

Pattern-1 has not been located exactly, but it may be linked to the Extension locus (determines chestnut) on equine chromosome 3. Pattern-1 increases the amount of white in the coat and is necessary for full expression of the leopard pattern (not to be confused with the Leopard gene.) Yes, the terminology is confusing!

The first set of characteristics produced by the Leopard allele includes mottled skin, striped hooves, and a white sclera in the eye. White ear tips can also occur. These characteristics are not definitive, as other color genes may cause them, but almost all horses with the Leopard gene show at least one of them.

Horses with the Leopard gene may show other white markings, including the normal face and leg markings. If the leg markings are not present, white may still show on the cannon bones in what are generally called lightning marks or lightning stripes.

Another thing the Leopard allele may do is to introduce interspersed white hairs in either of two patterns. Frost gives a fairly uniform distribution of white hairs over the body, most prominent over the hips and in minimal cases only over the hips. Unlike classic roan, the roaning develops after birth and increases with age up to a point. The dark head and legs of classic roan are generally not visible in this pattern. Unlike grey, the horse eventually reaches a relatively stable color.

Snowflake has a similar developmental pattern, but is most prominent on the foreparts and the white hairs are concentrated into small white spots.

Extreme frosty or snowflake patterns may develop into a speckled appearance, white with small colored areas. All leopard-complex roans may also have varnish marks, with areas over bony prominences (notably the nasal bones and hips) retaining dark pigment.

The Leopard allele may also produce larger but symmetrical white markings, generally starting with a few small white areas over the hips and working forward and downward until the whole horse is white, with the flanks and throat being the last areas to lose color. This is the pattern most strongly influenced by the pattern-1 gene. If the pattern-1 allele is present, white is more extensive than if it is not present. Full white is only possible with the pattern-1 allele. These symmetrical white markings are usually present at birth, though they may increase with age.

Finally, the Leopard allele can produce colored round or oval spots over the body. In most cases, these are visible only against a roan or white background, but occasionally they can be seen against pigmented areas of the coat. The spots may be darker or lighter than the base coat color.

Surprisingly, these spots are more likely and more numerous if the horse has one Leopard allele and one wild-type allele. If the horse is homozygous for Leopard (has two Leopard alleles) the spots are more likely to be absent or sparse.

Finally, two doubtful or deleterious aspects of the Leopard allele may be noted. First, leopard interacts with black-pigmented hair to make it brittle. The result is the sparse manes and rat tails often seen on leopard-complex horses whose base color is black or bay and who retain dark color in their manes and tails.

Second, homozygotes for the Leopard allele are generally night blind. This is rarely a problem with modern usage of horses, but should be kept in mind if riding a homozygous  Leopard over unfamiliar ground in darkness.

The named horses in Tourist Trap all have the leopard allele. I’ll describe Raindrop, Token, Splash, Freckles and Dusty as we get to the combinations of leopard markings that each represents. In fact,, I’ll give the full color genotypes I’ve given each.

I photoshopped this to brighten it a little. It's a gray day and the original was very dim.

March 28: Sunrise 7:22 am, sunset 8:31 pm for 13 hours 9 minutes of daylight. We’re still gaining 6 3/4 minutes a day. Yesterday that pesky ice from the November rain was just about gone from the pavement. except north of hills. Melting snow was still refreezing – overnight low temperatures were below zero until a couple of days ago, and are still forecast to be well below freezing.

Things may be slick again today, though – it snowed last night. Two to four inches for Fairbanks, officially. The snow stake shows 22” so I got enough snow to make up for last week’s melting and settling plus 2”. The wind spinner is up and spinning a little, with only a little snow sticking to it. The roads? I’ll have to see when I drive to OLLI (Osher Lifelong Learning Institute) classes this morning for the last session of “The science of smell.”

P.S. The roads were blown clear where the speed limit was above 50, and packed snow on slower roads. Lots of water coming back home, though, and it’s likely to be icy tomorrow. And we finished the science of smell with a discussion of champagne and terroir. Wonder if I can work some of that into Derry’s appreciation of fine wine?

I meant to post on the leopard gene in horses today, but I just didn’t get the post finished. I took a few more pictures of melting ice yesterday, so I thought I’d put them up for today.

Note the difference between the left side of this block, which has been exposed to strong sunlight, and the side facing the camera. This particular block is either in the same orientation it had in the pond or upside down, as shown by the vertical fabric of the sunburned ice.

This coumn was a little better sheltered, but there is still some solar melting on the right side. Notice the clarity of the shaded ice.

The middle part, between the clear ice on the left and the wood on the right, shows the intergrain boundaries as seen from the end. This block must have been turned on its side relative to its original orientation.

The blocks for the single-block competition are 8′ by 5′ by 3′ and weigh a staggering 7,800 lb each. Needless to say, they are positioned by power equipment! The multi-block competition can have up to 4 carvers and use up to 10 blocks of ice, but the blocks are smaller–a mere 3′ x 4′ by 6′. Repositioning and stacking these blocks is done by cranes, and the crane operators really have a job hoisting these delicate carvings into precise position. Aside from Harvest Moment, the photos in yesterday’s post were all single block.

Lots of photos today–I finally got to the Ice Park Friday evening. Sadly, some of my favorites were too blurred to put in, as it got too dark for the available light and my hands weren’t steady enough.

To my surprise, most of the ice is being cut now, and stored in piles of sawdust for sale to other parts of the world and for next year’s sculptors. This is the last of last year’s ice.

They were cutting the ice for next year as we drove by, a little after 8 pm.

Although the ice looks perfectly transparent when it is handed to the carvers, in fact it is made up of multiple crystals. Impurities are concentrated at these crystal boundaries, and when the sun shines on the ice, the boundaries are the first places to melt. Pond ice normally grows down into the pond, so the crystals are long, vertical shapes. The result is that sunshine produces long, vertical “candles” of ice.

Sunshine on the carved ice can produce unexpected patterns within the ice, depending on how the grain boundaries are located relative to the carved surface. I’m not even sure what this sculpture was.

The black background is one of the black tarps they hang to try to keep the sun off of the ice. The patterning on the right side of this sculpture, Moonrise, shows the effect of the sun.

The crispness of some of the carving, even after exposure to the sun, is incredible. This is Horsin’ Around.

Sometimes the ice, warmed by the sun, seems to flow. The harpoon on this harpoon fisherman has bent down with the weight of the harpoon head,just aabove the right shoulder of the harpooner. The sculpture is Harvest Moment.

The sculptors put in an incredible amount of work for something they know will last only a few weeks–if that. This one is Angelic Keepers.

I still don’t know how the carver got the star in the ball. They are only allowed to use ice, water and snow. This sculpture is Autumn.

The white markings are an example of use of a slurry of snow and water–though I suspect it’s a little more complicated than that. This is Mask.

Six of my favorites are missing here, so I’ll give links to their online photos. My photos of Palace PetFreedom and White Silence were just too blurred by camera motion to use. The White Rabbit, Rule of Sabanna and Let it Be collapsed completely or in part before I had a chance to see them.

Added 2012: This post had become very popular, but it is not the only collection of photographs I have taken of Fairbanks ice art, or even the best. Other posts are:
More on Ice Melting
Ice Art Championships 1
Ice Again: Single Block by Daylight 1
Ice Sculpture: Single Block by Daylight 2
More Ice Sculpture: Multi-Block in Progress
Multi-Block Ice Sculpture 1
World Ice Art Championships Multi-Block 2
The Fairbanks Ice Park (Children’s Playground)

Beauty and the Beast

Thanks to Goodreads, I just finished re-reading Beauty, by Robin McKinley. I still love it, but it inspired me to revisit Walt Disney’s and Mercedes Lackey’s versions of the fairy tale, as well as the Perrault version. I can’t help but be intrigued by the parallels with McKinley’s version in both the Disney DVD and in The Fire Rose. I don’t read French, so I have been unable to read Le Belle et la Bete and find out whether the parallels are based on a common source.

First, there is the idea that Beauty is somewhat of a misfit before she comes to the Beast’s castle. In Beauty she is the plain one of three sisters, but as she grows older in the castle, her beauty begins to show. In the Disney version she is more of a misfit socially, though always a beauty. In The Fire Rose she is (by early 20th century standards) that most unwomanly of creatures, a (gasp) female scholar.

That leads to the libraries. In all three versions, Beauty (or Belle or Rose) loves books–and all three castles have amazing libraries. In all three, the library plays a strong part in convincing Beauty that the Beast is really a person. In all three, Beauty and the Beast read to each other–though in The Fire Rose it is primarily Rose (the Beauty of that version) who reads to the Beast.

The Fire Rose doesn’t have the element that the servants can only be released from their enchantments when the Beast is, but the half-overheard conversations between the breezes and the occasional animated bit of furniture in Beauty seem to me to foreshadow the conversations between Lumiere and Cogsworth in the Disney version.

I’m going to have to re-read Rose Daughter, another Beauty and the Beast retelling by Robin McKinley.

Mercedes Lackey Trivia

Thursday: “He thinks I don’t realize that the killing would not end just because we had surrendered.” Mercedes Lackey. Context?

From The Black Gryphon. Urtho is explaining why he is continuing the war against Ma’ar.

Friday: “With an active two-year-old underfoot, I often wonder if I’m going mad.” Mercedes Lackey. Context?

From The White Gryphon. Skandranon accuses Amberdake of getting senile, and Amberdrake replies, “Hardly senile, though with an active two-year-old underfoot, I often wonder if I’m going mad.”

Saturday: “Everything changes eventually. Only a fool would think otherwise.” Mercedes Lackey. Context?

From The Silver Gryphon. Tad is musing on his and Blade’s chances of survival—they’re doing all right as long as nothing changes.

Sunday: “You can’t bring back the dead with more blood!” Mercedes Lackey. Context?

From Magic’s Pawn. Savil is trying to convince Tylendel that blood-feud is wrong. (She’s not getting very far.)

Monday: “A priest with no vocation is worse than no priest at all.” Mercedes Lackey. Context?

From Magic’s Promise, when Savil, Radevel and Vanyel are wondering why Father Leren is so hostile to Vanyel.

Tuesday: “Things usually become cliched precisely because there’s a grain of truth in them.” Mercedes Lackey.

From Magic’s Price. Vanyel is pointing out to Stephan that the cliche about music having power to change the world has some truth behind it.

Yes, I took the first six books about the history of Valdemar in order. Helps me keep track of which ones I’ve used! Next week will be random SFF again.

Wednesday: “White flakes were drifting down from a dark gray sky, forming lacy tables on the grass and fluffy balls on the bushes.” Bowling. Context?

From Homecoming. Roi is seeing snow for the first time. The rest of the paragraph continues: “The paths were clear–part of the same weather shielding that kept them dry when it rained–but Roi sent his chair as close to the edge of the path as he could, and reached through the weather shield to the white stuff. It was cold, and when he pulled his hand back, he found that the weightless stuff turned to a few drops of water in his hand. ‘It’s ice,’ he said wonderingly.”

Sunrise at 7:48 am, sunset at 8:10 pm for 12 hours 22 minutes of daylight. We’re gaining a pretty steady 6 minutes 43 seconds a day, and it’s actually above freezing today! Paved roads are wet over asphalt or wet over ice over asphalt–driving on the latter being like driving on a wet ice rink. Gravel roads are still covered with packed snow. I hope it stays warm enough to get the paved roads clear of ice, but it can stay cold a bit longer for the gravel.

The snow is still here but the level is sinking. Mostly due to compaction–there’s no melting to speak of on the ground. Buried dark objects are starting to melt out a little, though. The snow stake shows only about 20 ” on the ground, and the wind spinner, the one that accumulated all that snow, bent over and was buried earlier in the winter, popped up yesterday and is again spinning whenever we get a breeze.Snow is beginning to melt and drip off roofs, sometimes leaving interesting open laceworks behind. That’s trees and sky showing through gaps in the ice just above the shingles on the porch roof at Wolf Run.

It’ll be weeks before I can plant anything outdoors, but the first seed order arrived today. Beets, lettuce, wax beans… Think I’ll set up the fluorescent lights!

White Horses

This post has been updated, with more photographs.

A few horses are all white, with dark eyes and pink skin. These are not to be confused with aged greys, which may have a pure white coat but retain dark or at least mottled skin. This type of white can occur from the spotting genes we have discussed as producing pintos, especially if more than one type of spotting gene is present. There is also a type of dominant white which is lethal if two copies of the allele are present but which if one white and one wild-type allele are present produces a healthy white horse.

Remember also that many of the dilution genes we have discussed can produce a very pale cream color often mistaken for white, though most of these horses have light eyes.

All white marking genes on horses, from a conservative white star to a white horse with colored ears, seem to work by preventing the pigment-producing cells from getting to parts of the horse’s body. They do not affect or replace other genes for color. Thus no matter how extensive the white markings on a horse, it will still carry alleles at all of the color loci we have discussed. Further, it will pass those alleles on to its foals.

The white spotting genes grouped as “pinto,” “paint” or “parti-color” may occur in any combination consistent with the survival of the foal. (Two copies of the frame allele at the frame locus, for instance, results in white foal syndrome and early death regardless of what else is present.) A horse could easily have one frame allele, together with two each for sabino-1, tobiano and splash. Because the white areas from these alleles tend to affect different parts of the horse, the result could be a white horse. When bred to plain mates, the offspring would probably be spotted.

Horses with spotting due to a single locus can also be white or nearly white, if they are close to the extreme version of that pattern. Several of the spotting patterns converge to a “medicine hat” or “war bonnet” pattern with maximal white. This is probably most common in so-called tovero horses—those that combine tobiano spotting alleles with any of the non-tobiano alleles at other spotting loci.

There is one type of pink-skinned white with dark eyes that does not appear to produce spotting in the offspring. White to white breedings of this type, however, always produce some colored foals. Examination of the numbers of white and colored foals suggest that two white alleles at this locus are a prenatal lethal—the foal never develops or is aborted so early that the breeder assumes the mare has missed. This type of white is believed to be due to a dominant gene.

The white allele seems to have a surprisingly high mutation rate. Thus whites have been produced from colored parents in several breeds, and then reproduced as if they were dominant whites. I do not know whether DNA proof of parentage was available in these cases, however.

I do not believe a gene test has been developed for this type of white. Gene tests at other loci could be very useful, however, in determining what other color alleles the horse carries and could pass on to its foals.

White is a spectacular color and for that reason was popular in the age of horse power for flashy coach or cavalry horses. At least two western heroes–the Lone Ranger and Hopalong Cassidy–rode dominant whites, Silver and Topper. The downside? Keeping a white horse clean may be a problem, and the pink skin may be subject to sunburn.

We broke 12 hours of daylight Friday, 2 days before the equinox. Why? And is this just due to my being close to 65 degrees North, or is it a more general anomaly?

There are two parts to this peculiarity. One is latitude combined with the finite diameter of the sun, which can be calculated. The other is the refraction of the atmosphere, which varies from day to day and can only be estimated.

Let’s take latitude first. Sunrise and sunset are defined as the time that the upper edge of the sun is just visible above a flat horizon. “Equal days and nights” (which is what equinox means) assumes the dividing line between day and night is the time when the center of the sun is on the horizon, assuming light moves in straight lines. If the sun rose vertically, as it does at the equator, it would rise at a rate of about 1 solar diameter a minute, and the calculated sunrise time based on the center of the sun would be only half a minute after the time the upper edge first showed.

At higher latitudes, however, the sun appears to rise at an angle and sunrise and sunset appear slower. At 65 degrees latitude the sun’s path at the equinox is 65 degrees from the vertical, and a little trigonometry stretches that half minute to about 1 minute 10 seconds, or twice that in day length. Latitude alone is still not enough to allow our days to be 12 hours 15 minutes long at the equinox. For that, the refraction of the atmosphere becomes important.

The apparent break in the spoon handle is due to refraction.

Everyone is familiar with refraction, though you may not know it by that name. The optical illusion of a broken spoon in water is caused by the fact that the speed of light in water is less than that in air. Yes, the speed of light in vacuum is constant, but in any other transparent medium it moves a little slower. When it crosses a boundary between two transparent media with different speeds of light, any light rays not moving at a right angle to the boundary are bent. Air is one of those transparent media, and while the speed of light in air is not a great deal slower than that in vacuum, there is enough of a difference that the bending affects what we can see.

The actual difference in speed depends on the density and moisture content of the air, which in turn depend on pressure, temperature and relative humidity. Air near the ground is almost always denser than that above it, and this is particularly true at sunrise. The change with height is gradual, and thus the light rays are not bent sharply, as in the water-air interface, but curved along the earth’s surface. Objects far away appear higher than they are, and this certainly applies to the sun at sunrise. The amount by which the sun appears higher in the sky than it really is will depend the atmospheric density and how it changes with height.

For practical purposes the time of sunrise is calculated assuming that the upper edge of the sun is visible when the center of the sun is 50 minutes of angle—almost a degree—below the horizon. This also means that the sun at the equinox will rise not quite due east, as it “rises” while it is still physically below the horizon and slightly north (in the northern hemisphere) of east. The difference, however, is slight.

Refraction is also responsible for the fact that the sun appears to flatten as it approaches the horizon when setting or just after rising. The part of the sun closest to the horizon is more strongly affected by atmospheric refraction than is the upper part of the sun, so the two appear pushed together and the sun appears flattened, rather than round. I’ve probably overused this in Tourist Trap.


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