Night Owl Pedigrees

Mr. Prospector: The Big Picture

Author: Jane Nemecek, published: 5 Sep 2023

This article was written in the heat of the battle. During the season that saw several devastating breakdowns, and subseqently even calls to banish some bloodlines that must not be named from the thoroughbred population.

Thoroughbred discussions are a nervous place these days. With every new breakdown, the wave of sensitivity and searching for answers reaches new levels. And so does the blaming of Mr. Prospector as a primary source of unsoundness in modern thoroughbreds.

Even if you're not a Mr. Prospector fan, please, leave it aside for a moment. I want to show you some critical aspects of his influence that debaters don't consider - and I suspect they mostly don't know them.

Before I start on Mr. Prospector, I should state my opinion on breakdowns. First, I'm sure they don't have a single, universal cause, but rather various reasons and, in some cases, maybe even a sum of circumstances leading to the fatal injury. Given these assumptions, I don't believe any quick, easy solution can ever work.

Actually, I go so far as to think that the immediate situation - a) track condition - track, surface, physical forces at the moment, b) horse's condition - his constitution, harm done by the inappropriate work, regime, nutrition, or even exhaustion - are far more significant at the moment of injury than ANY name in its pedigree. Is it reasonable to blame the fourth generation of ancestors for a bad step in the race? Kill me, I don't think so.

But those are my personal beliefs. Also, I am not going to teach Americans about the dispositions of their domestic bloodlines - I loved Unbridled's Song and hated to see injuries in his foals, so you're not going to catch me red-handed fiercely defending any sireline. However: I will gladly advocate the need for rational discussion and a complex approach.

As a thoroughbred population analyst, I would like to contribute to this complexity with the overview of Mr. Prospector's influence - global, not just American; with his role and importance in pedigrees; and first and foremost - with some hard data on his supposedly "extensive" use and inbreeding.

Incidence in pedigrees

Everybody sees Mr. Prospector in pedigrees of unlucky, fatally injured horses. But during these discussions, no one ever mentioned an elemental question that suggests itself after such discoveries: What are Mr. Prospector's incidence and inbreeding in the healthy population?

To answer that, I will use my statistical analyses of Graded performers: while not "a population," it's a sufficient sample of hundreds of horses. And since sires and dams of Graded winners and non-winners are the same animals, it's not wholly unreasonable to think that we can use it as the best available approximation for the population. So, let's start:

I believe that the last two characteristics are as close to the actual incidence of Mr. Prospector in the thoroughbred population as we can ever get.

Translated to the common human language, almost every American horse has Mr. Prospector in his pedigree, and half of them are inbred to him.

It would mean that if we see Mr. Prospector in every fatally injured horse, and every second one is inbred to him, it would not be called a crippling sireline. It would be called a direct proportion to the whole population.

But after this short summary of statistical data, I can imagine that many readers are surprised and stunned by their absolute value in many tens of percent. So we need to clear also further aspects of the situation:

Is Mr. Prospector's pedigree incidence excessive?

Several numbers I've mentioned just don't sound "proportionate" or "moderate." Indeed, 50% of inbreeding to Mr. Prospector or his presence in 90% of pedigrees are very high figures.

Another thing we need to know about Mr. Prospector's incidence - in the current global thoroughbred population, these numbers are common.

That's not saying that they are proportionate or ideal - but common. To understand, we need some comparisons and measures, starting with Northern Dancer, a leading American sireline with a 36% incidence. Northern Dancers would actually top Mr. Prospectors, when it comes to inbreeding incidence. And if you worry about Mr. Prospector's presence in almost all American pedigrees - Northern Dancer is present in ALL of them, at the average of FOUR TIMES per pedigree. It's not well possible to count Nasrullah due to the old age of his sireline, but in the fifth generation of pedigrees, he's even more common than Northern Dancer.

Clearly said, on his American home scene, Mr. Prospector is a fitting component in pedigrees, not a beast that broke loose. And it's not quite his fault that most of the racing public doesn't know it.

When looking beyond the American borders, we even find such figures as a 60% incidence of Turn-To's sireline in Japan, or European inbreeding to Northern Dancer in 67% of Group performers. We'll get to the international data later, but it's vital to know that while Mr. Prospector's numbers may not be ideal, they're NOT out of proportion to the other bloodlines, and go from this point.

While we discuss Mr. Prospector's American numbers, I want to comment on another common concern in Mr. Prospector/inbreeding debates: the supposed "tendencies to linebreed" of American breeders.

Do American breeders like linebreeding?

People familiar with my work know that I don't just map stallions' influence and bloodlines; I also analyze breeding strategies in pedigrees. I started this work because a cumulation of sirelines becomes a real problem in European pedigrees. American fans should know at least a basic fact: American breeders don't like inbreeding very much.

Some form of linebreeding is present in 14% of American pedigrees, and breeders obviously hesitate to cumulate any bloodline more than that, with only random horses below 2% of the population having this type of pedigree.

Does 14% still sound too much? In fact, it's a striking difference to Europe, where linebreeding is present in almost 29% of pedigrees, and an additional 22% carry the same sireline three times. It can even be four or five times in extreme cases.

You're not going to see anything like this in American pedigrees. For the sake of objectivity, linebreeding to Mr. Prospector stands out in American statistics as an apparently intentional strategy, but still, we're talking about a mere 6% of the American Graded performers.

To complete the picture, there's no better way to demonstrate American distaste for linebreeding than with nicking statistics. From 11 living American bloodlines, 7 have one or zero attempts at linebreeding, and two more have random cases below 1% of the population.

Brief Euro-American comparison

I don't want to mess the article too much with this topic, but the core of the European situation is simple: much more Northern Dancer, much less Mr. Prospector. Most current European Mr. Prospectors are Dubawis (Seeking the Gold) and Iffraajs (Gone West); Street Cry (Machiavellian) is already moving to the second generation, and Kingmambo to the third.

Mr. Prospector is missing in about 50% of European pedigrees, but surprisingly, 31% of Group performers are inbred to him. It's about 2/3 of American inbreeding, but to be exact, we're talking about 344 American runners vs. 195 European ones: 57%. If Mr. Prospector was the main cause of breakdowns, Europe should have at least half of the American fatalities!

Being a European-based author who sees retired two-year-olds and rested chasers, I'm not delusional about European racing and its "health." Also, I miss any statistics on fatalities. But so many obvious Mr. Prospector fatalities are clearly not the case, and a pure absence of any breakdown concerns, all the more so connected to a single bloodline, sends a powerful message on its own.

Maybe not just about Mr. Prospector, though - maybe also about training, racecourses, different conditions for horses? I'll leave this one up to your imagination.

Inbreeding to Mr. Prospector? Here's the thing.

The fact that almost every American horse has Mr. Prospector in pedigree, and many of them are inbred, is the first omitted aspect. The second one is even more difficult to notice. It's related to the dynamics of sirelines.

Trust me on this one or not, but when we talk about sirelines, inbreeding is a function of time. You can't use it too early - imagine Sunday Silence in Japan, who has only sons and grandsons at stud: 2x3 inbreeding is not something you usually want, so you have to wait a bit. But not too long, because once the foundation sire reaches the 6th generation, he disappears from pedigrees, and inbreeding is no longer an option.

However, the "window" to create inbreeding is not that short, with at least three reasonable equine generations (3rd to 5th). But you still need one more thing to make it work: a sireline successful enough to make the inbreeding happen.

This one is not as easy as it seems. As a breeder, you can randomly inbreed to any stallion, but to make a POPULATION impact, you need either a super successful stallion or a really strong sireline. The first case is rare: only legendary stallions like Secretariat or Seatle Slew surpassed 5% of the population. But other stallions need good sons, daughters, and basically any horse in their multi-generation progeny that can pop up in pedigrees, so that the original stallion can create enough cases of inbreeding in the population.

As I explained, Americans are not big fans of direct linebreeding. But inbreeding positions also occur "inside" pedigrees: When you look at the enclosed pedigree diagram, you can see how many stallion posts outside the linebreeding exist, and real-life cases of inbreeding combine all these options.

To cover so many different posts in pedigrees, you need even more than a successful sireline: You need a wide enough sireline to be commonly present in the population, on various positions in pedigrees, throughout several generations. This way, inbreeding can occur when mating horses from various different bloodlines, not dependently on a particular direct sireline.

Speaking practically, current American thoroughbred population has only two sirelines capable of this behavior: Northern Dancer and Mr. Prospector.

Hypothetically, there's also Nasrullah, but here's the problem: Nasrullah as a foundation sire is too far in pedigrees, and the recent four generations of the sireline are mostly a single lineage: Bold Ruler -> Seattle Slew - A.P. Indy - Tapit. There are only few attempts to inbreed to A.P. Indy, and Tapit is too young, with his grandsons barely entering the stud. I mentioned Seattle Slew, but you can tell for yourself if 5.7% of pedigrees with his inbreeding is enough for you to notice in random pedigrees.

As for other sirelines, they rarely reach 5+ percent in particular generations of current pedigrees, and as I've mentioned, linebreeding, even when feasible, is not a favored option. More often, we see random inbreeding to stallions belonging to these sirelines, like In Reality, Buckpasser, or His Majesty. But in such cases, the "super successful" rule applies: These stallions were no Secretariats, and inbreeding to most of them has only about 1-2% incidence in the population, at best.

So, we're left with Mr. Prospector and Northern Dancer as the only sirelines capable of creating a noticeable number of inbreeding in the population. And we come to a crucial difference between them: Although they were born only nine years apart, Northern Dancer had a rocket start at stud, and nowadays, he reaches far further than Mr. Prospector.

Mr. Prospector's sireline reaches the maximum of 5-6 generations, and only in his oldest lineage of Fappiano. However, Unbridled Song's daughters still create inbreeding within 5-generation pedigrees, and stallions like Distorted Humor, Curlin, and Speightstown are only grandsons of Mr. Prospector: a stage of development that Northern Dancer left behind a long time ago. Veteran sires War Front and Hard Spun are rare exceptions; otherwise, Northern Dancer has reached the 9th generation of pedigrees. Three more than Mr. Prospector.

Even more importantly, there's a specific for American pedigrees: 2/3 of Northern Dancer's influence is beyond the 5th generation already, hidden entirely from our view. What we see in pedigrees are residues of Northern Dancer's direct, early influence, consisting especially of several specific domestic branches: Danzig, Dixieland Band, El Prado, Storm Cat, and Vice Regent. Otherwise, the presence of Northern Dancer in the sixth generation alone is higher than in the whole five generations before! Hence, the capacity of sireline to create inbreeding, a "visible" inbreeding, is limited already.

But in no way is this the case of Mr. Prospector: Naturally, with the 2-5 generation descendants as stallions, we see almost the entire Mr. Prospector's sireline "live" in five-generation pedigrees. And unlike Northern Dancer, we watch at least 11 domestic branches & their development during their prime.

Let's summarize: Northern Dancer is already behind the fifth generation of pedigrees, with an incomparably higher incidence than Mr. Prospector. He does have many cases of inbreeding in the population, close to Mr. Prospector's numbers. But we must be also aware that many current "3x5" inbreedings to him are, in fact, something like 3x5x6x6x6x7 figures. Which is a thing that Mr. Prospector is absolutely incapable of, by the way.

The only other modern and prolific bloodline in American pedigrees is A.P. Indy, but he is two decades younger than Mr. Prospector and can't have the same branching power, length of lineages, and incidence. All other bloodlines are too old and branched to be judged comprehensively as a sireline (Nasrullah or Turn-To) or too rare to notice when they create inbreeding in pedigrees (Hyperions, Ribots, etc.).

What I am saying here is simply this:
It's a current state of development of all living bloodlines that shows us the incidence of Mr. Prospector and inbreeding to him as the most striking events happening in current American five-generation pedigrees.

Can this explain Mr. Prospector's total inbreeding incidence and his appearance in "breakdown" pedigrees? Well - I was not given any schoolbook for interpreting sirelines' dynamics. Only my experience tells me that it's not wise to ignore a very probable link between Mr. Prospector as a leading inbreeding stallion and him being basically the only stallion positioned to do so.

Mr. Prospector vs. the population

As I mentioned, Mr. Prospectors are now called a disaster in modern pedigrees, and there are calls to stop using "such bloodlines." I can imagine that we stop using one living stallion, but a sireline that has been around for five decades? It's not exactly a viable plan. I'm being a little ironic here, but once again, the ease of creating such "solutions" reveals that people are seldom aware of most contexts associated with such an old, strong sireline.

Let's start with a basic picture: Mr. Prospector's role among current American bloodlines. Mr. Prospector is a co-leading sireline in American pedigrees, with about 34% of incidence. A narrow leader is Northern Dancer, and Nasrullah is distant third with 16%. If you see this as "bad," know that other regions are in a much worse situation: Australia has 70% dominance of Northern Dancer, and Europe even 80% of him. Can you guess who spared America of a similar fate? Here's a hint: his name begins with M.

You may also be interested in the dynamics behind these numbers. While the European & Australian situation among the leading sirelines got more out of balance with every of the past four generations, the American bloodlines keep getting MORE into balance. Three leading sirelines are strengthening at the cost of others, which is not ideal - but it's three up to 35% incidence, not one up to 80%.

Moreover, Northern Dancer doesn't seem to take a dramatic lead anytime soon. Neither does Mr. Prospector. The U.S. situation seems well stabilized and open for some future options, particularly if the world could save Plaudits (Mucho Macho Man), Man o'Wars (North American Tiznows, South American Put It Backs, or European Warnings), or Commandos (probably too late for Include, but not for South American Dubai Dust). No other region worldwide can say the same.

But even after all this text, we need to deal with one more severe aspect of the whole situation. Mr. Prospector is not just an American power: he's an international sireline.

Mr. Prospector's global role

Mr. Prospector has been home in Europe since his very first crops in the late 1970s - Hello Gorgeous won the William Hill Futurity in 1979 and Miswaki the Prix de Salamandre a year later. Stallions like Miswaki, Woodman, or Machiavellian had enormous impact on the European breeding, despite a later replacement by different tail-male branches. Somehow, Mr. Prospector always had problems to start the same empire as he did in the U.S.: all European lineages feel somewhat short, short-lived, or at least "not so proggressive" and slowly developing.

However, even when heavily fragmented, modern Mr. Prospectors play a critical role in Europe. I've mentioned absolutely horrifying European incidence of Northern Dancer with 80% of runners - and Mr. Prospector is his sole competitor. Not a strong one anyway, with 16%, but so far, Mr. Prospector keeps Europe from a complete disaster. 80% + 16%: you can do the math.

Australia follows similar trends as Europe, especially due to massive load of European shuttle stallions; but lucky for all of us, it also has a strong tradition of Turn-To. Imported Mr. Prospectors remain another option and Australia seem to quite get a taste for them recently. And for the record, can you guess who's the strongest competitor of dominating Sunday Silence in Japan, with his roughly 60% incidence? Sure enough: domestic Kingmambos.

Considering global breeding, we need Mr. Prospector as a world-class bloodline to "dilute" Northern Dancer. With all those 60-80% figures of Northern Dancer and Sunday Silence, how would you feel about losing Mr. Prospector as the only alternative? About even "banning" him?

But the bigger picture doesn't end even here, with statistical incidences of bloodlines worldwide. Let's return to Mr. Prospector's homeland, where he's not just a stallion power: Mr. Prospectors profile themselves also as damsire talents. And I'm not talking about the "success" influence like Awesome Again, Scat Daddy, or - have we all forgotten? - Galileo. I'm talking about the "saving rare bloodlines" damsire influence of Mr. Prospector.

Mr. Prospector's contribution to genetic diversity

It starts with an enormous impact on A.P. Indy's line. Mr. Prospector himself was a damsire of Pulpit, Mineshaft, Malibu Moon, Flatter & Congrats; Unbridled became a damsire of Tapit, Quiet American of Bernardini, and Distorted Humor of Constitution. Mind you: Nasrullah, specifically A.P. Indy, is the second lineage that keeps American bloodlines balanced against Northern Dancer! It means that actually, Mr. Prospector saved the American breeding for the second time, and I cannot be more literal.

Other than that, Mr. Prospector is the third sire of Macho Uno (Plaudit's last hope before siring Mucho Macho Man), Super Saver (one of Native Dancer's last hopes), and Maxios (one of Blandford's last hopes). Straight Strike is a damsire of Lonhro, a desperately needed Turn-To counterbalance to Australian Danehills. Woodman was a damsire of More Than Ready - another Turn-To international hope, while Seeking the Gold was a damsire of Blame, who still carries the hope for the American part of the line. Seeking the Gold is also the third sire of Nyquist, one of Uncle Mo's sons - hopes for any continuation of Grey Sovereign. Miswaki is a damsire of Dalakhani - one of the last hopes of European Nasrullahs. And since Tiznow is not gone yet, it's worth mentioning Mr. Prospector as a damsire of Gemologist, a Gr.1 sire in Chile, and Unbridled's Song as a damsire of Tourist, the major US hope for the Man o'War's survival.

Let's summarize: A.P. Indy + Mill Reef, Grey Sovereign, Turn-To on several continents, Plaudit, Man o'War, and Blandford. That's a lot of work for current breeding and the future of bloodlines - if any comes for some of them.

Postscript: What if...?

I've spent quite some time presenting factors why we should be careful about judging Mr. Prospector in current pedigrees and tossing around ideas for hostile actions. I should explain my thoughts on "But what if Mr. Prospector is..." as well. What if genetic research enables us to see, in five or ten years, that there's really some hereditary issue?

Since Mr. Prospector has been around for half of the century, I don't think there's any "solution" to "him" at all. We certainly can't cut him off the existing pedigrees - and since he's in most of them, we can't stop using horses with his influence either. Now that we've seen his global importance, it would be extremely undesirable anyway. Even if breeders would be willing to listen to such calls - and I seriously doubt that (and side with them).

Also, we can't imagine "genetic predispositions" as some physical "pre-cracks" in bones. There would be, most likely, some defects on the biomolecular level. And even if we identify genes or markers and develop tests - I'm afraid it will still be only physical activity that can determine the horse's ability to withstand training and racing.

In history, we've seen multiple times horses with handicaps, sometimes quite severe, who were able to overcome them and race at the top level. The truth is, it's not predispositions themselves that are determining: horse's compensation mechanisms are. When everything's "working," a horse can overcome conformation flaws or even malformations. How are we even going to treat these issues...?

What we surely can do is to learn our lessons, and think through breeding, training, and racing adjustments. But we can do it anyway, right now - completely independently on Mr. Prospector or any other name.

However, you can notice that there's hardly a place where demonizing any stallion can help. Or have any sensible consequence or effect. So the next time someone shoots "Unbridled," remember that we can't cut him out of Tapit's pedigree. And that we need Tapit and his sons. And even a lot more than that, Australia needs Machiavellians like Per Incanto and Street Boss.

It's from this advanced point that we can start working things out.