05 February 2015

'Footmarks On Stone,' or, Why This Blog Is Called Noah's Ravens

The year is 1802. In South Hadley, Massachusetts, a farmer called Pliny Moody discovers something strange in a slab of rock. Closer investigation seems to indicate that the unusual markings in the rock are footprints, with three narrow, spread-out toes, very similar to the footprints of birds.

The mysterious track-maker was referred to as 'Noah's Raven,' in reference to the first bird set out from the ark after the flood in the book of Genesis; presumably these footprints were thought to have been made by the raven, which flew 'back and forth until the water had dried up from the earth,' and, apparently, eventually came to land in western Massachusetts.

The 'Noah's Raven' specimen at the Beneski. [photograph by the author]

Of course, 1802 was a different time. Most people were inclined to accept the Biblical account of the flood as a scientific truth, while the real identity and history of the track-maker remained unknown. For its day, the assessment that the footprints were made by a bird was not a bad one, as the tracks clearly display strong similarities in appearance. Noah's raven, however, was no bird; rather, it was a nonavian theropod dinosaur, whose fossilised footprints had been discovered some 190 million years after it made them on an ancient lakeshore, and a full 40 years before the word 'dinosaur' would even exist. These tracks were the first dinosaur fossils uncovered anywhere in North America.

At the time, though, the bird identity stuck. As more tracks in stone were found throughout the Connecticut River Valley, local folk noticed the typically three-toed, birdlike form and often referred to them as 'turkey tracks;' they used these foot-marked rock slabs as stepping stones, doorstops, and curiosities to impress visitors. In the early 1830s, these strange stone footprints drew the attention of one Edward Hitchcock, a clergyman and a disciple of the natural sciences.

Bust of Professor Edward Hitchcock, found in the Beneski
Museum's Hitchcock Ichnological Collection, amongst the tracks
he gathered throughout his career. [photograph by the author]

Despite his religious background, his fervent and lifelong personal devotion to Christianity, and his explicit rejection of evolution (following Darwin's 1859 publication of On the Origin of Species By Means of Natural Selection, which was in the twilight of Hitchcock's life), Edward Hitchcock came closer to realising the footprints' true nature than anyone yet had. In 1835, as a professor of natural theology at Amherst College, he identified the footprints as belonging to 'praeadamic' (that is, predating Adam) bird species, some of which would have been quite large — bigger even than the largest living bird, the ostrich Struthio camelus.

It was Hitchcock's belief that the birds that made these footprints, along with the other fossil plants and animals being uncovered in Europe and America, existed in a time between God's creation of the Earth and His creation of man. He believed there was a gap of many thousands of years between Earth's creation and humankind's appearance, during which Earth's environments changed substantially and multitudes of species were divinely created and died out. While he may have been a theologian and an critic of evolution, Professor Hitchcock was a far cry from a Biblical literalist.

But it wasn't just evolution's detractors who identified these tracks as those of giant birds. In fact, they were quite important to one of the theory's greatest champions, Thomas Henry Huxley. Huxley thought all birds descended from a prehistoric ratite-type animal, as he considered ratites (ostriches, rheas, emus, cassowaries, kiwis, tinamous, and some extinct lineages) to be the most primitive extant birds. However, Huxley's theory and the avian identity of the track-makers were not to last, because in 1861, the world was introduced to Archaeopteryx.

Archaeopteryx lithographica. Or maybe A. siemensii. Whatever, it's
the Beneski Museum's cast of the 'Berlin specimen,' one of the most
beautiful and iconic fossils in the world. [photograph by the author]
Archaeopteryx, discovered in Germany and exhibiting traits both birdy and reptilian, is actually bog-standard in today's world where nobody is surprised about another small feathery dinosaur being described. But in the mid-1800s, it was groundbreaking; small dinosaurs were uncommon finds at the time, something that blurred the line between them and birds was revolutionary. It has since then been touted as the 'first bird,' though today palaeontologists are not entirely settled on whether it was both, just the second half, or neither.

Whether or not Archaeopteryx was truly a bird or just a very birdlike nonavian dinosaur, it certainly killed two birds with one stone: Huxley's hypothesis that the progenitor of birds was a monstrous emu-like creature, and Hitchcock's identification of the Connecticut River Valley footprints (which are now known to be roughly 40 million years older than Archaeopteryx, and even at the time were known to predate the German discovery) as those of prehistoric birds. For the first time, Hitchcock's tracks would be recognised for what they truly were: not the footmarks of Biblical ravens, or ancestral ratites, but of nonavian dinosaurs.

Interestingly, Hitchcock never accepted this identification of his treasured tracks. He maintained that they were made by birds until his death in 1864. Why this is isn't entirely clear, but it may have to do with perception of dinosaurs in Hitchcock's time. While today, dinosaurs are known to have been active, agile, warm-blooded (or, at least, not cold-blooded) creatures with upright gaits — exactly the kinds of animals that would have created the Connecticut River Valley footprints — in the 19th century, dinosaurs were depicted as decidedly more reptilian creatures, cold-blooded sluggards with their tails dragging along behind them. I wonder whether Hitchcock would accept a dinosaurian identity for his track-makers if he had been aware of the dinosaurs of the 21st century, or if he would still reject the notion. He wrote as a footnote to his 1836 poem 'The Sandstone Bird' that his track-making birds were more 'perfect' than the known dinosaurs (or as they were called at the time, saurians), so perhaps the idea that certain groups of animals were inferior to others, not uncommon even among scientists of his day, tainted his opinions regarding saurian creatures being the makers of his beautiful trackways.

A close-up look at one of the Noah's raven tracks. The three pointed,
spread toes give the classic footprint shape for theropod
dinosaurs, including modern birds. [photograph by the author]

At any rate, the fossil footprints are probably the greatest highlight of the Beneski Museum's collections. In addition to the sheer numbers and diversity of the tracks housed in the museum, they have a long history that's nearly as fascinating as that of the creatures that made them millions of years ago, and so I chose Noah's raven, America's first dinosaur, as the namesake of my little website. From the very beginning, dinosaurs captured the curiosity and imagination of scientists and laypeople alike, and from the very beginning, dinosaurs and birds have been hopelessly intertwined, just as they are today, as we know now that birds are the only dinosaurs left alive. The mission of the natural history museum is to present the stories of life in a way that captures the imagination and ignites curiosity, and to foster understanding of life's connectedness and ever-changing nature through evolution. What a better way to celebrate that than with the name of a creature that embodied all those ideas, even in their early days?

- 'Hitchcock Ichnology Collection.' Amherst College.

- Genesis 8:6-7. The NIV Study Bible.

- Pick, Nancy. Curious Footprints: Professor Hitchcock's Dinosaur Tracks & Other Natural History Treasures at Amherst College. 1st ed. Amherst College Press, 2006.

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