The bones that have now been recovered and saved for scientific study include all anatomical parts of numerous individuals of the extinct peccary, Platygonus compressus. Both sexes and all ages are represented, from tiny jaws of peccaries newborn, or perhaps actually not yet born when they died, to skulls of big, tough boars. North America was peccary headquarters for millions of years. Numerous extinct kinds have been discovered, and there are two kinds still living in South and Central America one of which, the collared peccary (Tayassu angulatus), ranges as far north as southern Texas, New Mexico, and Arizona. Peccaries are sometimes called “wild pigs” and they do look much like pigs, but the real relationship is not very close. They do not belong to the pig family (Suidae) but to a distinct family of their own (Tayassuidae). True pigs have never been native to the Western Hemisphere.
The living peccaries are rather small animals, seldom over 20 inches high at the shoulder. They usually run in bands and are inoffensive vegetarians, although their sharp, curved tusks give them a somewhat fierce appearance. Some travelers have told horrendous tales of being attacked by large bands of peccaries, but more reliable observers report that they will not attack except as a last resort when they are molested. The normal use of the tusks is to pull up and cut roots for food. Our extinct peccaries from Cherokee Cave had the same habit, because several of the tusks that we found have grooves worn in the sides from rubbing against gritty roots. In fact, these ancient peccaries must have looked and acted very much like their surviving cousins, except that they were about twice as large.
We had hoped to find remains of other animals that lived at the same time as the peccaries, and in this we were successful, but only one of our additional discoveries was particularly striking. Apparently the trap in which these animals were originally buried, the sinkhole or fissure from which their remains were flushed into the cave, was specially adapted for catching peccaries. Few other animals fell into it, but we did find scanty remains of a black bear, a raccoon, and a porcupine, all much like those still living in the region when white men arrived there. The unexpected discovery was an extinct armadillo, related to the recent Texas armadillo but larger. This is an important new record, because St. Louis is much farther north than any other known occurrence of an armadillo, living or extinct. Recent armadillos range no farther northward than Texas, and the only comparable previous finds of extinct armadillos were in Florida.
Both the armadillo and the peccary, also a warmth-loving animal, suggest that when these animals lived there the climate of the region was milder than at present. They may have lived just before or just after the last glacial stage of the Ice Age, for these were times of relative warmth. Aside from this inference, it is impossible to give a very close answer to the question as to how old the bones are. The difficulty is increased by the fact that the bones were not originally buried where they are now found. They may have lain for a long time in their original tomb before being washed into the cave. They are pretty surely more than 20,000 years old, and it is not likely that they are more than 500,000 years old—the interval gives a good deal of leeway. In any case, they are very ancient in terms of human history but are quite young as fossils go.
Hermetically sealed in continuously damp clay since shortly after the animals died, the bones have been unusually well preserved. The marrow and other soft animal matter have decayed and disappeared, but the hard bone substance has not changed at all. The bones were roughly jolted when they were flushed into the cave and many of them were broken then, but even the fragments are strong and fresh and some of the unbroken bones look almost as if they were the remains of last night’s pork roast. This beautiful preservation made the bone-digger’s job much simpler and quicker than it usually is. It was not necessary for us to apply preservatives to the bones immediately on exposure or to encase them in reinforced plaster before moving them—procedures usually necessary with fossil bones. After carefully exposing them on one side, they could immediately be pried out of the clay without damage. The problem of cleaning them was also unusually simple. No slow grinding, scraping, and chiseling to remove the rock in which most fossil bones are buried. We simply soaked them in a wash basin for an hour or two and then scrubbed off the clay with a stiff brush.
With the help of Mr. Hess and the gang of workmen he provided, we developed a mass-production system in our bone-digging. The bones were piled up in boxes as we dug them out, and the full boxes were then taken up to the De Menil house, where we had what we called our bone laundry. Here, in the old kitchen, they were set to soak, and when the clay had softened sufficiently, they were thoroughly scrubbed. The clean, wet bones were then spread out to dry on tables in the dining room. Like fresh bones, they do tend to crack when dry; the fact that they had not been dry for thousands of years is a reason for their exceptional preservation. So the next step in the production line was to paint them thoroughly with thin white shellac and then to dry them again. The shellac soaks in sufficiently to seal all the incipient cracks and forms a transparent protective coating that will preserve them practically forever. Then they were ready for the last step and were moved on along the line into the parlor, where they were carefully wrapped and packed in boxes and barrels for shipment to New York. Between the cave and the mansion, our bone mine, laundry, shellackery, and packery hummed all day and sometimes far into the night. In only one week we had what would ordinarily be a good bag for a whole collecting season. Not only that, but nine-tenths of the bones were all ready for study or exhibition when we shipped them, requiring none of the usually tedious additional preparation in the New York laboratory.
So the mystery of the bones in the brewery was solved and a goodly sample of the bones moved on to the Museum by way of the De Menil house. De Menils and Chouteaus; peccary knuckles and beer; caves and palaces—these were some of the ingredients in a unique adventure in bone-digging. It was a curious mixture, so strange that at times we were hardly sure whether we were awake or dreaming. But as I write these last lines a peccary skull looks at me blankly, reassuring me that the fascinating medley of history and prehistory was real.