95.1 Imagine a world where the average woman had 10 children over her lifetime…and the average man had over a 1000. What sort of kinship relationships and terminology would develop? For human beings, this would go way beyond plural marriages or even harems. Fortunately, we’re not talking about people, but about horses.
95.2 Among horse breeders, equine kinship consists of a mix of “human” terms and those particular to the field. I’m sure you’ve heard some of the basic ones…a male horse is a stallion, a female is a mare. When young, they are colt and filly. If you’re a horse, your father is your sire…your mother is your dam. Sons and daughters are…well, sons and daughters…altho the overall offspring of a male is his get…of a female, her produce.
95.3 I thought it would be fun today to compare and contrast human and horsey (their word) systems of kinship, but with this caveat: Altho these terms are ingrained over hundreds of years of use, they are by no means absolutely universal. Fanciers of different breeds look at things in slightly different ways…and indeed what we’ll be talking about today pertains most specifically to thoroughbreds. After all, their stud book dates back to 1751, 46 years before the recording of human births and deaths was required by British law…which should tell you something about how serious they took their horses!
95.4 What’s more, while the nomenclature and the thinking behind it predates scientific concepts of DNA inheritance, there is a small but vocal cadre of nudniks who believe traditional terms should be adjusted to reflect modern genetic principals. Most in the hobby are perfectly happy with the traditional system, but there is occasional agitation…even so, some terms are used by different individuals in different ways…sort of like: Well that’s how I was always told is was supposed to be done. As an outsider looking in, I am left with a somewhat confusing overall picture. Not that much different from human kinship, nez pah?
95.5 Chart 336 shows the pedigree for a horse named Asterisk. Its father’s entire family is called his sire line…its mother’s, his distaff line. Some of its ancestors are marked with an *, and this indicates what’s called the tail male line and the tail female line…that is, the the male line thru the sire and the female line thru the dam. Members of the tail female line are often called 1st, 2nd, 3rd, etc. dams. Less frequently, members of the tail male line are 1st, 2nd, 3rd, etc. sires. The other special term indicated is Asterisk’s maternal grandfather, who is called a damsire or broodmare sire.
95.6 There is no problem with mating horses that are related to each other…in fact, inbreeding as a description generally only applies out to 3 generations…altho some would say as many as 5. Since horses don’t have last names, the most compact way to refer to one is: “by Sire, out of Dam, by Damsire.” A horse is properly BY its sire and OUT OF its dam…the surest way to announce you’re a newbie is to say “out of Sire.” Obviously, this system is tilted towards the males…traditionally, it was thought that the male blood contributed more than the female. Why don’t you also mention the sire’s sire? Because if you’re talking about a particular male horse, you probably already know…seriously, that’s how they think of it. The entire pedigree is important of course, but this shorthand refers to the 3 most important ancestors: father, mother, and paternal grandfather. Its similar to the Spanish custom of double surnames…a combination of your father’s last name and your mother’s maiden name, which of course is her father’s last name, indicating her paternal line.
95.7 Because horses don’t get married, and can be bred to relatives both close and remote, the occurrence of individuals who are less closely related than full siblings, but more closely related than full 1st cousins, is much more prevalent than with humans. Human half-siblings, with CR of 1/4, are what you’ll most likely encounter falling in between full siblings (½) and full 1st cousins (1/8). True, with the breakdown of the traditional family unit, half-siblings are becoming more common…to the point where where the term “quarter siblings” has evolved to describe unrelated half-siblings “on the other side.” But in human kinship, “enhanced half-siblings” are unusual…that is, half-siblings related thru both paternal and maternal lines…not so in the equine sphere, where they are the frequent and of course intentional. Here are some basic definitions I plucked from the internet to get us started…
95.8 Chart 337 diagrams the first 2 definitions. The important thing to notice is that half brothers occur thru the dam only…on the other hand, what in human terms would be half-brothers sharing the same father are in horsey terms called by the same sire. They are not thought of as being “related,” at least to the extent that they cannot be described as “brothers.” This odd dichotomy is the result of the fact that a horse can have a dozen half-siblings thru its mother, but a 1000 or more thru its father. Thus, having a common sire is considered of less significance, at least as far as the terminology is concerned. As the old joke goes: Your horse is a grand nephew of Secretariat? Him and 5000 others…
95.9 Obviously 2 horses with the same sire are related in a genetic sense, and a few cranky reformers insist they too should be called half-brothers. The rest of the fraternity ignores them. As with language in general, it’s just a case of making oneself clearly understood…using the terms in a different, “better” way is going to get you in trouble, pure and simple. But what’s shown in Chart 337 is considered standard.
95.10 Chart 338 takes the “half sibling” (A–C) and “by the same sire” (D–F) cases back a generation. In human terms, all these would be called “enhanced half-siblings”…A and D would be “3/4 siblings,” half-siblings on one side, 1st cousins on the other, for a total Coefficient of Relationship of 3/8. The others would be half-siblings and half-1st cousins, a CR of 5/16. But what are they in horse terms…can we match these 6 cases to the definitions we are examining?
95.11 Well, the definition of brothers in blood fits D (same sire, dams full sisters) and A (same dam, sires full brothers.) The definition of three-quarter brothers fits only C (same dam, sires by same sire.) Presumably, B would be nothing beyond half brothers (same dam)…E and F would simply be by the same sire. But does this nomenclature hold across the board? Sadly, no. For example…
95.12 …let’s take Uncle Wiki…thankfully, they agree on the definitions of full siblings, half siblings, and by the same sire. They also concur on brothers in blood. But then all hell breaks loose. Their definition of three-quarter brothers fits B, not C…same dam, sires are half brothers (i.e. sires have the same dam, different sires.) But they go on to say that three-quarter brothers can also mean same dam, sires who are father and son…as shown at left as G. Whoa…didn’t see that coming…but there’s more.
95.13 Uncle Wiki defines three-quarter brothers in blood
as the flip side of three-quarter brothers…that is, either same sire, dams that are half-sisters (i.e. dams have the same dam, different sires), which would be E…or same sire, dams who are mother and daughter…shown at right as H. Then there’s three-quarter genetic brothers…and that would be same sire, same damsire (i.e. dams have the same sire) and that gives us F. Notice that “dams have the same sire” presumably implies “but different dams,” otherwise we’d also be defining D, which they’ve already called brothers in blood.
95.14 Notice too that C, the only thing that our original definitions labeled as three-quarter brothers, has fallen thru Uncle Wiki’s cracks…it falls under no definition of three-quarters, and so is presumably nothing more than half-brothers. Quite a mess, no? And I’m sorry to say, it gets worse…Chart 339 summarizes our original definitions, Uncle Wiki’s…plus the style book for an organization called American Horse Publications, and 3 more sources off the net. A double dash “–” means the term was not defined.
95.15 Under Source 4, I and J are marked with an asterisk since we haven’t seen them yet. Below, I is what in human terms are called double 1st cousins…the parents’ generation is colored orange and green because they can be either a same-sex pair of siblings or one of opposite sexes. And J in human terms is an irregular double cousin relationship…full 1st cousins thru the dams who are full sisters, and half-1st cousins thru the sires, who are half-brothers (i.e. same dam, different sires)…presumably it wouldn’t count if the sires were by the same sire (i.e. same sire, different dams.)
95.16 Like I said, quite a mess…for three-quarter brothers, not one of our 6 sources agrees. Uncle Wiki and Source 4 label B and E exactly opposite. G and H are considered either the same thing or 2 different things. At least brothers in blood and three-quarter brothers are 2 different things, right? Nope…Source 5 groups them together.
95.17 And the thing to keep in mind is: these terms are used routinely by horsey folk to describe various pedigrees, and they clearly mean something by them, and expect the reader will know what that something is. As sometimes happens, one column has grown into two…so next week I’ll take a stab at sorting it all out…till then, Hi-Yo G4BB, awaaaaay!…
So anyhow, here are 4 horses of a different color…top right is an especially dark “silver dapple”…bottom left is a “brindle”…you usually see that in dogs…top left and bottom right look to be “chimeras”…individuals with 2 different sets of DNA…like those cats you see whose faces are 2 different colors, split down the middle…
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