Geology and Paleontology of Blue Beach Fossil Site

Blue Beach Fossil Museum 127 Blue Beach Road, HanTsport, Nova Scotia, b0p 1p0, cANADA

Blue Beach: Geological Background

Blue Beach was once an ancient shoreline part of a narrow brackish-water seaway trapped between Africa and North America after these continents collided about 370 million years ago. Both the African and North American sides of the seaway were bordered were bordered by newly created mountain chains. The land met the sea as a narrow strip of coastal lowlands swampy forested lands replete with rivers, streams, ponds, deltas which formed a diverse region of many micro-habitats. Erosion of the mountains was rapid and continuous with the sediments ultimately winding up washing down across the coastal plain and into the seaway. Blue Beach was on the African side of the seaway, and today one can see a series of layered cliffs and indeed the beach underfoot itself is composed of the same. These are the ancient sediments of Africa deposited just at or near the shore that was 350 million years ago. The rocks exposed at Blue Beach are known as the Horton Bluff Formation with the site being the type section. The formation is part of several other rock units that together make up the larger Horton Group. These are the oldest sediments in the Maritimes Basin and can be found in all four Atlantic Provinces and underlying the Gulf of St. Lawrence and portions of the Grand Banks

An Important Evolutionary Event Romers Gap The evolutionary story that the fossils of Blue Beach represent is the first appearance of air-breathing, four-legged animals on the planet tetrapods about 350 million years ago. Blue Beach (also known as Horton Bluff) provides two lines of evidence on these amphibians, our earliest limbed-ancestors:

1. Their fossilized bony remains. 2. Their footprints and trails.

These fossil of Blue Beach are placed within a period known as Romers Gap. IA.S. Romer, a research scientist from Harvard University, decided to review the whole of tetrapod evolution, with a special eye towards the most-primitive starting point where recognizable terrestrial groups begin. These groups are the ones that led to all subsequent terrestrial vertebrates that have evolved to today. After reviewing all of the existing evidence and research, he came to a distressing conclusion that there was a 20+ million year gap in the fossil record during the most important period when animals were evolving from fish to amphibians. Romer knew that before the gap tetrapods existed, but that these were primitive forms. One look at their primitive fish-like skeletons tells us they were not the root from which all subsequent land animals evolved. They could be likened to a separate branch on the tree and not actually leading towards those later forms that interested Romer most. However, after the gap, in rocks of about 340 million years in age, those primitive fishlike tetrapods were replaced by at least seven groups of land animals: the terrestrially- adapted amphibians. But by the time we first see them its apparent these new tetrapod lineages had already been evolving for millions of years, and were fully organized into their separate and quite diverse clades. Romer was frustrated by this gap because he desired to study the initial radiation of these clades from their common ancestry. Instead he felt as though he could only watch the last few minutes of the movie. In acknowledgement of his recognition of the gap in time, it is now named after him.


Since Romers day, the fossil record has been increased to a limited degree with additional collections from several sites around the world. Romers Gap continues to remain largely silent, with the exception of only three sites where tetrapods are known:

1. Blue Beach, Nova Scotia (350 mya). The oldest and most-productive Romers Gap site. 2. Dumbarton, Scotland (345 mya). A fairly complete single skeleton, no other specimens. 3. Castlecomer, Ireland (345 mya). A single lower jaw fragment.

Blue Beach thus plays a critical and meaningful part towards our slowly improving but growing knowledge of the first conquest of land. In this regard it has already far outstripped the predictions in 2000 of its limited potential to contain vertebrate remains. Here is the first evidence of a diverse and productive ecological community existing so far with the Gap, and indeed, is the earliest such community known. This has not only altered sciences views regarding the mode and tempo of this transition; it has truly surprised leading experts who thought this was a slower and less far-reaching process.

History of the Blue Beach Site (1841 - 1995) The birth of vertebrate paleontology in Canada took place one fine day in 1841 with the discovery of footprints by Sir William Logan at Blue Beach (then known as Hortons Bluff). In various works between 1863 and 1896, J. W. Dawson, the eminent Maritime geologist and Nova Scotian, reported on the rich fossil assemblage at this beach. He named several plant species, several new trace fossil types (including Logans tracks, named Hylopus logani), as well as a diverse fish fauna such as the shark-like acanthodians, primitive bony ray-finned palaeoniscoids, and an impressive giant lobe-fin rhizodontid fish that was then known by only a few scales and teeth, and by a fragment of one lower jaw. The next major developments were the 1966 discovery of the first known tetrapod bone from the locality by researcher Donald Baird, the 1972 publication of new information on the vertebrate fauna by Robert Carroll of McGill, and the discovery of additional footprint varieties by Sarjeant and Mossman (1978). The discovery of additional trace fossils and footprint material stimulated interest in the site, and lead to numerous scientific papers on all manner of subjects save the most important aspects of all: the tetrapods and the fishes themselves. Efforts to collect their bony remains proved that they were indeed very scarce at the best of times. Skeletons were not seen; rather one was dealing with loose scatters of isolated bones and fragments. After about 35 years of optimism about one day understanding its vertebrate fauna, the key researchers eventually concluded that for Blue Beach unfortunately, the site would probably never yield anything more than a few enigmatic glimpses at best (Clack and Carroll, 2000 Amphibian Biology).


The BBFM Project (1995 to Present) The first time I encountered Blue Beach was in the spring of 1995. I had collected fossils from the West Coast to Ontario, but had never ventured further east. I have always had a strong urge to uncover and understand fossil sites wherever I went, but my first impression at Blue Beach was profound puzzlement and I liked that. This beautiful and wild shoreline had some of the strangest geology and some of the least-documented realms of all fossil research - the Early Carboniferous tetrapod ecosystems, especially Romers Gap. By 1998 I met Dr. Barry Cameron of Acadia University, and together by pooling our collections and our knowledge, and undertaking to import a large research library of papers and texts relating to our fossil collections, we hoped to begin our own series of publications to describe the Blue Beach fauna. There were many fossils, and the worlds highest and fastest-rising tides saw to it there would be plenty more as time went on. I could identify only a very small number of them. The rest, including the best, were a mystery to everyone because many of them had not been found before. I came back to Nova Scotia every year until 2000, building a very large collection that filled my apartment to its limit. Our efforts with Acadia University were important beginnings. But I believe that the days I met my future partner Sonja Wood at the foot of her driveway as I prepared to take to the beach was the point destiny truly chose to move me in a mysterious way. The Blue Beach property belongs to Sonja and ironically in 1995 approached the Nova Scotia government in with the idea that a museum should be built at Blue Beach though not not knowing the true significance of the site. Unfortunately, no interest was shown. In 2000, we joined and pioneered the Blue Beach Fossil Museum and Research Centre which opened in 2002. Our goal was to create a purpose-built, on-site interpretive museum that concentrated on real fossils, real problems in paleontology, and real ongoing discoveries. Our work together on The BBFM Project has led to a new understanding and appreciation for the site as being truly world-class, and to have generated widespread interest by leading experts who now view our collection as the global standard. Using some of our pre-2003 specimens, Martin Brazeau (then of McGill) in 2005 was able to properly identify the giant rhizodontid fish from Blue Beach no longer Strepsodus or Rhizodus, but it proved to be a unique genus with several unique jaw and shoulder features that warranted the name Letognathus which literally means jaws of death, annihilation or ruin. Evidence that these ferocious predators grew to perhaps 5m (16 ft) in length can be shown through the fossils in the BBFM and at McGill collections. We have now also shown that there were anywhere from 6-10 kinds of tetrapods in existence at this time. This is an incredible diversity of early tetrapod life considering the sparseness of other tetrapod remains and knowledge during the time of Romers Gap. Clearly this collection of fossils, as it now stands exceeding 70,000 lbs, has the potential to generate many decades of important scientific research. Whereas bony remains are ultra-rare, footprints are abundant. As noted in the attachments, ours is the largest collection of the oldest fossil footprints in the world. It is the largest collection of Carboniferous-aged tracks known today and rapidly growing with ~1750 specimens as of January 2011. The next largest known collection is from the younger Union Chapel Mine site in Alabama. The tracks recovered by the BBFM in the last 15 years are the most important fossil-track discoveries of recent times yet remain virtually unstudied. We believe that the knowledge inscribed in these rocks will become the Rosetta Stone for scientists to decipher the still poorly understood Carboniferous record of tetrapod footprints. The study of these Carboniferous tracks has been muddled mostly by uncertainties stemming from the smallness of older more accessible collections. With the growth of new collections from Blue Beach, Union Chapel Mine and Pottsville within the last two decades, a re-assessment of early Carboniferous tetrapods through their fossils and footprints - and their ecosystems is long overdue. The Blue Beach collection will


likely play the leading role in this research and is partnering with Dr. Spencer Lucas, footprint expert from the New Mexico Museum of Natural History in this study.

The Museum of Tomorrow During its first eight years of operation, the BBFM has shown tremendous potential to become ranked with the most popular and important fossil destinations in Canada. The reasons are many including the story it tells about how fishes formed limbs out of fins and then crawled ashore to become the land animals of the future. Besides being one of the most important classic transitions in the history of life, it is also one of the greatest remaining unsolved problems in paleontology Romers Gap and so ongoing research is vitally important. Blue Beach is also easily accessed by the general public, being close to major highways and infrastructure as well as having approximately 450,000 people within 100 kilometres or an hours drive away. Currently, without any special promotional efforts on our part, we receive over 10,000 annual visitors (most of who just go to the beach). A substantial portion of the visitor base is students from regional schools and universities, as Blue Beach has become a growingly popular spot to have field trips. There are few things that children and students get more excited about than the chance to hunt and maybe discover fossils. Teachers and professors alike cite their visit to the BBFM as one of the top highlights of the year for them and their groups. To give these precious fossils their due respect and share this rich new cornucopia of discoveries with the world, a new purpose-built facility must grow out of our home-based museum. The collections must be properly preserved and displayed. If done right, this opportunity can be result in the creation of a world-class museum, research centre and geotourism site benefitting all Nova Scotians, and indeed humanity as a whole, as Blue Beach holds the keys to one of the most important stories evolution has to tell. The non-profit Blue Beach Fossil Museum Society has been created to take us towards this new phase and has been designated by the CRA as a charitable organization. We are working with local government to have the site declared a Special Place, protected under the Special Places Act. The land-use zoning restrictions have been changed so that a commercial institute can be built on this site. We have garnered a wide range of support from local citizens, governments and scientists, and firmly believe Blue Beach is headed for worldwide attention and prominence. To date, we remain the sole philanthropists for this project and operate the existing facilities through personal resources and visitor donations. To realize our goal, we have done much planning to position the project to receive significant financial support from government, business and private partners. We welcome your interest in the Museum and hope you and your organization will consider becoming funding partners with us to create a dynamic new museum that will tell the story of this chapter in the history of life on earth that it so richly deserves. Sonja Wood and Chris Mansky The Blue Beach Fossil Museum Society 127 Blue Beach Road Hantsport, Nova Scotia B0P 1P0 Tel: (902) 684-9541 Email: [email protected]

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Geology and Paleontology of Blue Beach Fossil Site