The historical record on different lines of descent in the Thoroughbred shows that the winnowing out of male lines has gone on from the beginnings of the breed. And the great majority of male lines disappeared in the first 75 to 100 years of the formation of the Thoroughbred. By the late 1700s, there were only three principal male-line ancestors, each coming through only a handful of sires, even at that point.

By the late 1800s, the three main male lines were swelling out of equal proportion to signal that the Darley Arabian through Eclipse was becoming overwhelming in its domination, and that situation has compounded through the 20th century.

In 1957, to take a year, there were 24 stakes winners in the U.S. from stallions of the Herod line. That seems like a decent number until you consider that stakes winners descending from the Godolphin Arabian-line sire Fair Play alone numbered 31 that year.

The 1950s pointed out some interesting things about the two lesser male lines of Byerley Turk/Herod and Godolphin Arabian/Mathem. Most importantly at mid-century, the statistics showed a continuation for Herod through two sources. First was The Tetrarch (by Roi Herode). A foal of 1911, The Tetrarch was the best of Roi Herode’s quite numerous good horses. The Tetrarch was notably special among the lot, however, and he was little less amazing at stud. The generously proportioned gray sired racers of exceptional speed, as well as unexpected stamina, including three winners of the St. Leger at Doncaster among his offspring.

There would have been more and greater honors for The Tetrarch if only there had been more foals. Had he possessed even average fertility, The Tetrarch might well have resurrected the Herod line in his own image. Slim fertility, at best, doomed the great gray’s opportunities of turning the tide.

The other line of significance for Herod was that descending from Tourbillon. Marcel Boussac’s son of the great French racer Ksar sired a mighty brood of athletic racers who possessed speed and durability, plus enough class to vie for the classics and great all-age prizes.

Ten of those 24 stakes winners for Herod in 1957 descended from Tourbillon, including three from the Claiborne stallion Ambiorix and four from the Almahurst Farm sire Nirgal.

For the Godolphin line, 31 of its 32 total 1957 stakes winners came through Fair Play, and 16 of those were through Man o’ War. Those numbers sound pretty good, at least at first glance.

Even 65 years ago, however, the writing was on the wall. The two male lines of more scarce representation were represented by too few individuals, and the opportunities to breed to these was too narrowly focused on a handful of superb sires like Tourbillon and Man o’ War. Some of their stock has continued in the male line at the highest level through the ensuing decades, resulting in champions like Precisionist (Crozier back to Tourbillon) and Desert Vixen (In Reality back to Man o’ War), as well as Tiznow (Cee’s Tizzy back to In Reality and Man o’ War).

The stats for the Eclipse line, however, tell the tale of inevitability.

In 1957, some 65 years ago, there were 410 stakes winners tracing to Eclipse. Primarily these came through Bend Or (Doncaster), with 165, but the vast spread of them virtually guaranteed that some of these would breed on to become the overwhelming lines of today.

Among the lines of Eclipse operating with high success at the time were the branches of Swynford and his classic-siring sons St Germans (Kentucky Derby winners Twenty Grand and Bold Venture, the latter the sire of Triple Crown winner Assault) and Challenger, the sire of Horse of the Year Challedon and champion Gallorette; of Vedette and his successors, including St. Simon, to such international champions as Ribot; of Bay Ronald and his descendants, especially Hyperion, who had sons as leading sires in North and South America, as well as in Australia; and then there were also the “American” lines of Domino, Ben Brush, and Broomstick, whose point of importation in the male line came back in the 19th century.

All these are Eclipse, and there are more.

The irresistible push from Bend Or’s typhoon of genetic success was first seen to great effect in the States through Bend Or’s greatest son: Ormonde through Flying Fox to Teddy and his early- to mid-century sons Sir Gallahand III and Bull Dog, as well as grandson Bull Lea; additional importations came through Phalaris, with his sons Sickle (Preakness winner Polynesian and multiple classic winner Native Dancer) and Pharamond (Horse of the Year Tom Fool, classic winner Tim Tam, and Horse of the Year Buckpasser), then Pharos’s son Nearco provided the next wave with his sons Nasrullah and Royal Charger.

Now, several of those lines in male descent are no longer with us, or they are very rare at the higher levels of competition, including all the old American lines and such familiar stalwarts of mid-century breeding as Teddy and Hyperion.

The Bend Or line possessed and enlarged upon the volume required for a stallion or a sire line to have a realistic chance to continue, despite the slings and arrows of outrageous fortune that horses inevitably encounter, and today their percentage of the male-line representation continues to grow.