October 2012


I wanted to get pictures of one of the new horses at our barn, Dutch, to use for a post on sooty patterns. Dutch was interesting because he has the very dark forehand that some sooty buckskins get. I also thought artists that read the blog might find the abrupt transition between his body color and the black front legs interesting.

I had only seen Dutch at a distance, but I had gotten the impression he had somewhat paler-than-usual eyes. Light brown eyes are not uncommon in buckskins or palominos, so that would not have been unexpected. When I got close enough to take this picture, the reflection from his eyes looked off. (All the images in this post are larger than they appear, and since the details are small, I highly recommend clicking them to see the larger version.) Instead of looking pale brown, his eyes looked like the reflective gleam was in the wrong place. That is more noticeable in this face shot.

Over the years I have learned that odd reflections in the eyes sometimes mean the horse has a blue segment, and sure enough, that was the case with Dutch. Although he has no white markings at all, both of his eyes have flecks of blue. The largest one is located close to the bottom of his right eye, and is what is giving the odd reflection.

As can be seen in that photo, he has a number of blue flecks in that eye. His iris also has irregular patches of golden brown and darker brown, giving the whole eye a marbled look. Although it was more visible in brighter light, even without the light directly hitting the eye the blue areas could be seen.

His left eye had smaller flecks of blue that were much harder to capture on film. (This is the image that would most benefit from clicking, since the flecks are so small.)

He would be an interesting horse to test for splash white. So far a couple of individuals without white markings of any kind have tested heterozygous classic splash white (SW1). Perhaps Dutch carries SW1, too. It is also possible that there is some other yet-unknown cause for the blue sections in his eyes.

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If there is one thing that is consistent among purebred animals, it must be the desire for ancient – and preferably exotic – origins. The latest and greatest may be desirable with high tech equipment, but we seem to prefer our horse and dog breeds well-aged. In the past I have enjoyed giving a presentation that pokes a little fun about breed mythologies. I am fortunate that my audiences have, so far at least, all been good sports, because this can be a rather touchy subject for a lot of people.

That is unfortunate, because many of the accepted stories about the origins of various breeds have not held up to closer scrutiny. As geneticists continue to analyze different populations, it is becoming clear that some populations are not remnants of an ancient group, but rather relatively modern attempts to recreate those animals – or in some cases, a romantic notion of what those animals might have been like. For those that do not have a strong attachment to the original stories, the truth can be far more interesting.

That is certainly true for the research being done by the Village Dog Genetic Diversity Project headed up by scientists at Cornell University. They have been collecting samples from hundreds of semi-feral dogs in remote areas in Africa. Their findings have been somewhat surprising.

African village dogs are not a mixture of modern breeds but have directly descended from an ancestral pool of indigenous dogs

Meanwhile, modern breeds that have been thought to descend from African populations, like the Pharaoh Hounds (above, photo courtesy of Wikimedia Commons) and the Rhodesian Ridgeback, clustered with Western breeds.

These results are consistent with [previous results] showing that Salukis, Afghan hounds, and Basenjis cluster with ancient, non-European breeds, while Pharaoh hounds and Rhodesian ridgebacks do not. Although this coarse sampling (3 countries) is suitable for detecting truly indigenous versus reconstituted ancestry in putatively African breeds, analysis including village dogs from more regions will be necessary to better localize the ancestral origins of these breeds.

What is interesting is that two of the three modern breeds noted as clustering with the non-European dogs – Salukis and Basenjis – still allow crosses to newly imported stock. (More information on that is available on the new Genetic Diversity page.)

This study is reminiscent of the one done a few years ago on the origins of the Arabian Horse. The author of that study, “Speculations on the origin of the Arabian Horse breed“, found persuasive evidence that the modern Arabian was as much a Victorian construct as it was a uniquely pure, ancient breed.

These results permit formulating the hypothesis that the Arabian horse breed was created from many different breeds and populations, and the concept of breed purity, might refer, at most, to the present population with a history that does not exceed two hundred years

Obviously there are not many ideas more scandalous in equine circles than Arabians being created “from many different breeds and populations” with a history that does not exceed 200 hundred years (ie., 1809). To imagine that carefully preserved purebreds are mongrels, while feral dogs bred without any human selection in the streets of Africa are free from outside “taint” and “pure” descendants of ancient ancestors, really does turn what we think we know about our animal companions on its head.

Edited to link to the full version of the Głażewska “Arabian origins” paper.

This post ran back in the spring, but I never did add the promised page of links. That is up on the website now, though it is still a work in progress. Clicking on the “Genetic Diversity” tab up at the top of this page will take you to a link. 

The Equine Tapestry

My oldest son has been struggling with freshman Biology, so the concept of evolution has been on my mind a lot lately. I have also been reminded that evolution applies, not just to organisms, but of points of view. Sometimes it can be easy to forget that you once held a different view – unless of course you are foolish enough to write it down for others to find later. I have been writing about horse color long enough now that I have had that happen!

The reminder of this came from my husband. Longtime readers of the blog have probably picked up on the fact that I have a strong interest in the issues surrounding genetic diversity. It is, as I have mentioned, one of the themes that runs through the upcoming books. My close friends could probably warn readers that it is a tempting soapbox for…

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Just a little administrative stuff here. When I started this blog, what I had in mind was a place where people could talk about topics covered in the Equine Tapestry books. There is a lot of information in the first volume of the series, and more to come in the subsequent ones (I say this as I eye the huge stack of notes about pony breeds sitting here beside me), but even so only a fraction of the information is in the books. I though the blog could serve as a place to share that extra information, if it was wanted, but in many ways it has taken on a life of its own. I wanted a conversation, and I certain have gotten that. I just did not expect it to reflect my own rambling, subject-jumping speaking habits quite so closely!

But it is a conversation, and I encourage readers to participate. Feel free to leave a comment here on the blog itself, or send a message through email. You can find that by clicking the sabino horse image under the “Contact Me” button. Questions, observations, photos and links are always welcome. Sharing these makes for a richer experience for everyone.

I also encourage those who participate on Facebook to “Like” our page there. Because I am pretty strict about photo permissions here, and because WordPress is not set up for easy back-and-forth sharing of pictures, many readers use the Facebook page to link to interesting horses online. From time to time the subjects covered here get expanded upon over there. (I do have a personal Facebook page, but it is usually filled with terribly mundane comments about my family members rather than interesting images of horses.)  Clicking on the image below will take you to the page for Equine Tapestry.

I also keep a set of Pinterest boards with collections of links to unusual horses, all sorted into categories and, in some cases, testing status. I need to add to them, but Pinterest is a terrible place for encouraging time-wasting, as the completely unrelated boards full of recipes I will not make, and home decorating projects I will not start, would suggest. Separating out those personal boards and putting together an exclusively horse color Pinterest account is on my list of things to do, but that is a long list! Clicking on the image below will take you to the boards.

As a final note, I have some updates on the books themselves, but I will handle that in a separate post.

In the comments section of the last post, some posters noted the similarity of the white areas to fleabitten grey. That is not an uncommon thing with appaloosa patterns. Although it is easiest to think of the action of Leopard Complex (Lp) as a form of progressive roaning, where white hairs gradually replace the colored ones to form what American horsemen call varnish roan, in actual practice the process can go both directions. That is, it can add white hairs to lighten the coat, and it can add concentrated bits of color to speckle the coat. These darker hairs are sometimes called repigmented spots because they typically occur after the coat has already begun to roan out, or in an area that previously had white patterning.

The varnish roan mare at the top of this post is a very good example. I have run photos of Freckles before for the series of posts on appaloosa mottling. I have easy access to her, since she shares a pasture with my own appaloosa pony, Sprinkles. This particular image shows her coloring from four years ago, when the lightest parts of coat were an even mixture of white and color. At that time, had she not had such pronounced varnish markings on her body, and a sprinkling of dark spots on her hips, she might easily have been mistaken for a pale grey. (This particular photo was taken in early May, so she had not fully shed out for the summer and was just a shade or two darker than she would be in summer coat.)

Here is Freckles as she appears now.

Each year she has gotten more pronounced dark ticking in the roaned areas of her coat, even as she gets lighter in the areas that were colored. This lighter ticking is most noticeable if you compare the right hind leg in the two pictures. The repigmented specks first began to appear on her shoulder, but over time they have spread across most of her body.

This close-up of her topline shows just how closely this resembles fleabitten grey. In fact, if I use Photoshop to remove the hip spots and what remains of her varnish marks, the resemblance to a true fleabitten grey is quite striking.

I suspect some type of repigmenting is part of what was going on with the roaned areas on the horse in the previous post. With Freckles, the flecking ties visually with what is already going on with her coat, so it looks less jarring. With the horse from the previous post, the odd transitions between his colored areas and the patterned areas make him look a bit like you pasted together parts of a bay appaloosa and a fleabitten grey.

 

While searching through some old binders, I found some photographs of an unusual Appaloosa pattern. I apologize for the rather poor quality of the images, which were taken in a poorly lit arena using a traditional (non-digital) camera. I’ve tried to bump up the brightness without losing too much in the way of detail. Apparently the horse was never in the right position to get a good side shot, which is a shame.

He caught my eye because of how abruptly his coat transitioned to the dark areas of his pattern. Also unusual was how rounded the edges were. This is especially visible on his face and neck.

 

The other unusual aspect of his pattern was the “bleached edge” effect on some of the roaned areas. You can see one on the bridge of his nose, both in the picture above and this one from the front.

 

The above shot also shows how the roaned areas appear to “pool” around the dark parts of his legs. Dark leg marks like this are pretty common on appaloosas, but the nature of the roaning, which looks a lot like fleabiting on a grey, all in discreet areas (with those oddly rounded edges) while areas of relatively clear bay remain is quite odd. If this was an artistic representation, and not a real horse, I would have said the artist needed to work on more realistic transitions  on the legs.

 

On both the leg shots, the faintly whiter outline on the roan areas can be seen. The blanket pattern on his hindquarters, though, is pretty normal. I’ll include a close shot, since the spots show a really nice contrast between the two different types of halo-spotting. The darkest spots have halos that are made up of a mix of white and colored hairs, while the centers are colored. The centermost spot has a halo created by dark skin underneath white hair. The center of that spot is a mix of white and colored hair, though elsewhere there are spots that have dark skin halos and purely colored hair centers.

These photos are probably close to 15 years old now, and I never did learn the name of the horse. If anyone recognizes him, please drop me a note. I’d love to be able to look into his background.

Few posts on this blog have generated as much traffic as the ones about Wing’s Sable Sky, the American Saddlebred with a reversed dappled pattern. (Previous posts about her can be found here and here.) Posts about Sable Sky prompted Julia Bahr to send in photos of her Missouri Foxtrotter Rex’s New Taste of Dallas. Those images showed the progression of the roaning on Dallas as she aged, but because she is a palomino the effect was more subtle than that on Sable Sky.

Soon after that, Joanne Abramson sent pictures of her reversed dappled Miniature mare, Pacific Lady Godiva. Joanne not only had great current pictures, but a series of photos at various ages that show the progression of the roaning. Even more helpful, the base color on Godiva is black bay, so there is plenty of contrast. (For those that have read my book, Joanne may be familiar as she was mentioned in the Acknowledgements. She color tests her entire herd, and posts clear pictures and full testing status, including negative tests, on the Pacific Pintos site. For those with an interest in color, it is a wonderful resource that I highly recommend!)

Pacific Lady Godiva is homozygous for black (EE) and heterozygous at Agouti (Aa). She also tested positive for frame, making her a really good example of just how minimal that pattern can be. (Extremely minimal frames appear to be more common in Miniatures, in my experience.)  Just what might be causing her reversed dappling is open to speculation. But is is clear that the pattern developed over time. Here she is as a weanling.

Not in particular how little white there was on her face at this point, compared to her as a mature horse. Likewise, as a foal she does not appear to have white on her legs, yet as an adult she has an extensively roaned left fore as well as some roaning on the right fore. (In the first two images, she is seven years old.)

The early stages of the roaning are visible in these photos of her at age four. Like the Foxtrotter Dallas, the roaning is more pronounced on the face at this point.

This photo of her back was taken at age six. This placement is a bit different from the two gaited horses in that her patterning is more concentrated along the topline, whereas theirs appears to be more concentrated on the sides. In that way, Godiva is reminiscent of some of the odd Connemaras discussed in the earlier post Ponies Don’t Read. (I have it on my to-do list to contact the owner of Wintermist Sweet Shannon for permission to run photos of her. I have really good images, but nothing runs on the blog without express permission from the photographers, and sometimes that creates a bit of a delay on my part.)

What I also find interesting about Godiva is that her patterning, at least in photos, is not entirely symmetrical. She is more extensively dappled on her right side than on her left, as these face shots show.

I should add that this type of coloring does not really have a name. I have called it “reversed dappled roaning” for lack of any widely accepted terminology. Images of Wing’s Sable Sky – both Dee Dee Murray’s lovely photo and the snapshots that ran with the original Craigslist ad for her – have been widely shared across the internet. Many have called her “giraffe-marked”, which is certainly descriptive. It is also potentially confusing because that term is already widely used, along with the term lacing, for the pattern of reticulated spotting in Miniatures and other breeds.

Certainly the pattern on Godiva is similar in location, and lacing is also progressive. It does look a bit different, though. Cindy Evans took this pictures of Ace of Spades, a Miniature with lacing. It is quite possible that his pattern will progress a bit over time, but the way the pattern extends down the sides (and especially on the neck) on Godiva is a bit different.

But perhaps more importantly, the outline looks quite different. Lacing most often looks like a thin white outline. The pattern on Godiva is wider and has a softer, more diffused outline. (Hopefuly I have not given anyone vertigo by tilting the Joanne’s image of Godiva’s back to match the angle on the image of Spades!)

Seeing detailed images of the progression of this pattern was really helpful. I am really interested to see if the patterns on the three horses in these posts – Godiva, Dallas and Sable Sky – get any more extensive with age.

I also have to thank all the owners and photographers who are so generous with providing images and information for this blog. You help make putting together this blog such an enjoyable experience!

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