Before the Dinosaurs — The Lost Worlds Beneath the Scottish Borders

An Ocean Beneath the Hills

Across much of the upland Borders, the bedrock belongs to the Ordovician and Silurian periods. These names describe chapters in geological time, hundreds of millions of years before the valleys of Ettrick and Yarrow gathered their human stories. Many of the rocks familiar around Hawick, Ettrick and Gala began as sediment in the ancient Iapetus Ocean.

It is a remarkable reversal of the landscape we see now. A steep hillside can be made from material that once settled beneath the sea. The alternating bands visible in exposed rock can preserve the aftermath of underwater flows carrying sand and mud down into deeper water. Each deposit added another layer. Over immense stretches of time, those layers became the stone that now helps give the Southern Uplands their character.

Geologists call many of these sandstones greywackes. The name sounds unpromising, but the rock tells a dramatic story. Sediment could arrive in powerful underwater avalanches, spreading across the seabed before finer material settled above it. A landscape that looks solid and permanent was assembled from movement: grains carried, currents released and mud accumulating in an ocean that no longer exists.

The most easily overlooked beds can be among the most revealing. Dark mudstones and shales may contain the remains of small marine organisms. Their fossils can help scientists identify the age of rocks and compare layers separated by enormous distances. The Borders’ oldest stories are sometimes written in marks so slight that a passer-by would see little more than a scratch on stone.

Graptolites: Tiny Creatures with a Global Story

Among those marks are graptolites. They were colonial marine animals, and many of the forms important to this story floated in the sea. Individual members lived in tiny connected structures, producing colonies whose preserved outlines can look like delicate branches or little saw blades pressed into a dark surface. They are a long way from the imposing skeleton most of us picture when someone mentions a fossil.

Their scientific usefulness is extraordinary. Different forms appeared at different times, and some spread widely through ancient oceans. Recognising a particular graptolite can therefore help a geologist place a layer of rock within a much larger sequence. Something small enough to fit beneath a fingertip can connect a Scottish hillside with the history of the planet.

For a famous example, follow the A708 towards Moffat and the country around Grey Mare’s Tail. Dob’s Linn lies beyond the administrative Scottish Borders, in Dumfries and Galloway, but belongs naturally to this journey through the Southern Uplands. Its significance is international: it contains the reference point used to define the beginning of the Silurian Period, around 443 million years ago.

That does not mean the Silurian began at Dob’s Linn while the rest of the world waited. It means scientists selected a particular level in its rock succession as the agreed reference for recognising that boundary. The sequence and its graptolites allow a small Scottish locality to serve a much wider purpose. A place beside a road through the hills becomes part of the language used to organise Earth’s history.

There is something wonderfully Borders-like about the contrast. The landscape offers no grand announcement of its importance. The road bends through rough ground, the weather moves across the slopes, and the rocks sit where they have sat for generations of travellers. Yet this quiet corner helps scientists describe a transition that happened more than four hundred million years before any traveller could have stood there.

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When the Ocean Closed

The Iapetus Ocean did not remain forever. The landmasses on either side moved as Earth’s plates changed position. The ancient continental settings of what would become Scotland and England were once separated by sea; their eventual coming together forms part of the story behind the Britain we know.

The Southern Uplands preserve evidence of that changing ocean margin. As oceanic crust descended beneath another plate, sediment could be scraped from it and added to an accumulating wedge of rock. Layers were displaced, folded and stacked. This was no simple process of a seabed rising intact into hills: the material was caught in a vast system of movement and deformation.

Imagine a carpet being pushed from one end until it begins to buckle. The comparison cannot capture the full geology, but it helps explain why beds that began as relatively level deposits may now stand at steep angles. In a roadside exposure, the direction of a layer can be a clue to a much larger history of pressure and movement.

The hills of today are not those ancient mountains preserved without alteration. Erosion has removed enormous quantities of rock, and later events have reshaped the surface repeatedly. What survives is an exposed part of that long history. The stone beneath an upland road might record an ocean floor, while the slope above it belongs to a landscape carved much later.

It is a useful thought when looking out from a high viewpoint. Our film Above the Fog: A Morning on the Eildon Hills captures the Borders as a sweep of ridges, valleys and changing light. Beneath that beautiful surface are different rock histories, brought together in a region whose apparent calm conceals extraordinary geological change.

The Borders Moves into the Tropics

Now move forward to the early Carboniferous, around 350 million years ago. We have crossed a stretch of time greater than the entire distance between the dinosaurs’ extinction and the present day. The ancient ocean story has given way to another world, and the part of Earth carrying this region lies near the equator.

In the area geologists call the Tweed Basin, low ground supported rivers, floodplains and wetlands. Conditions changed as channels shifted, water spread and ground dried. Some deposits record shallow water; others preserve soils that formed beneath vegetation. This was a living landscape, with fluctuating water levels and places where floods could rapidly bury material.

The rocks associated with this chapter are known as the Ballagan Formation. They include mudstones, siltstones, sandstones and distinctive carbonate layers. Read together, they reveal a complicated environment rather than one unchanging swamp. The ground could be wet, exposed, vegetated or flooded at different times. Rivers supplied sediment; the landscape left a record of its changes.

The setting helps explain why these fossils matter. Early animals with limbs did not enter a neat division between permanent water on one side and comfortable dry land on the other. They occupied environments with pools, channels, mud and changing margins. To understand their bodies, scientists also need to understand the places in which they lived.

It is tempting to fill this scene with the wildlife we know. Resist that temptation. There were no familiar flowering meadows, no cattle and no birds on the riverbank. The vegetation and animal communities belonged to a much earlier Earth. A realistic reconstruction should feel recognisable in its water, sediment and light, while remaining deeply unfamiliar in the life it contains.

Romer’s Gap: The Missing Chapter

For many years, the early Carboniferous presented scientists with a frustrating shortage of fossil evidence for four-limbed vertebrates. This interval, often described broadly as around 360 to 345 million years ago, became known as Romer’s Gap, after the palaeontologist Alfred Sherwood Romer.

On either side were important pieces of the evolutionary story. Earlier fossils showed vertebrates with limbs that retained strong connections to water. Later ones revealed a wider range of animals and ways of living. Between them, the record was sparse. Scientists knew the transition had not simply stopped, but lacked enough fossils to follow it in detail.

A gap in the fossil record is not an empty world. Animals can live in great numbers and leave little that survives for us to find. Their bodies may decay without burial. Suitable rocks may be destroyed, concealed or never examined closely enough. What is missing can be the evidence, rather than the life itself.

That distinction turns the Borders discoveries into something more exciting than a collection of unusual local fossils. They supply evidence from a period that matters to our understanding of vertebrate evolution. They help bring detail into a chapter that had been difficult to read, showing that early Carboniferous communities were richer and more varied than the sparse record once suggested.

The headline is not that one animal in the Borders suddenly decided to leave the water and became our ancestor. Evolution is a branching history, and living on land involved many changes across many lineages. The discoveries help scientists investigate those changes, their timing and the environments in which they happened. That is a far more interesting story than a single heroic first step.

Stan Wood and the Eye That Saw More

There is a human story inside this immense timescale. Stan Wood, who lived from 1939 to 2012, was a self-taught fossil collector whose work helped transform knowledge of ancient Scottish life. His discoveries were the product of patience, close observation and a willingness to keep searching where a casual visitor might see only stone.

One of the key localities was Willie’s Hole, beside the Whiteadder in Berwickshire. Wood recognised its importance, and material from the locality became central to the investigation of early Carboniferous animals. The place-name has none of the grandeur of a famous prehistoric destination. That is part of its appeal: a river locality in the Borderlands helped open a window into a globally significant interval.

Finding a fossil is only the beginning. A fragment must be examined, prepared and compared. Scientists need to work out which parts belong together, what the bones reveal and how the surrounding layers fit into geological time. A promising discovery in the field can lead to years of careful work before its importance becomes clear.

Wood’s legacy continued through research and further excavation. The TW:eed project brought specialists together to investigate the fossils and their environmental setting. Its name points to the region that supplied so much of the evidence, while the work reached into questions shared by palaeontologists around the world.

We often tell Borders history through monarchs, armies, abbeys and industrial fortunes. Here, another kind of individual changes the story: someone looking closely at rocks, noticing what others passed and giving researchers something remarkable to investigate. The landscape did not reveal itself all at once. It needed an attentive eye.

Burnmouth, the Whiteadder and the Borderlands

Burnmouth is another important name in this story. Along the Berwickshire coast, rock exposures preserve early Carboniferous sediments and fossils. Beds can record environments and events on an ancient floodplain, including material carried together and buried by flows of sediment.

The Whiteadder localities offer a different part of the same broad investigation. Fossils from Willie’s Hole include several early tetrapods, and researchers have worked to place these discoveries more precisely within the Tournaisian, the opening stage of the Carboniferous. Burnmouth has also produced distinct assemblages from different levels in the sequence. The discoveries should not be imagined as one single moment frozen across the whole region.

Even the apparently straightforward question of age requires detective work. Spores preserved in sediment can help researchers compare beds between a coastal exposure, a river locality and a borehole. The fossil animal tells one story; the tiny plant remains around it can help place that story in time.

Coldstream belongs to this wider fossil landscape too. An important locality lies on the English bank of the Tweed, downstream from the bridge. That detail is worth understanding because the geological story crosses the modern boundary effortlessly. The Tweed is a border in our political geography; the ancient environment represented by these rocks did not observe it.

The pattern is deeply familiar to anyone who enjoys Borderland history. Our story of Rheged follows a world whose connections do not fit neatly inside modern lines. These fossils take that idea into a vastly older setting. To follow them, we must allow the landscape to be larger than the map of today’s council areas.

What Were These Animals Like?

Tetrapod means four-limbed, and the term embraces a vast evolutionary group that ultimately includes amphibians, reptiles, birds and mammals. In this early chapter, however, the animals are neither miniature modern mammals nor ordinary frogs. Their anatomy can combine features that feel familiar with others that reveal a very different way of life.

Some had broad, low heads and bodies suited to moving close to the ground. Limbs and joints offer clues about how they supported themselves and moved. Skulls, teeth and the arrangement of bones help researchers compare them with other forms. A small fossil can carry information about relationships that cannot be read from its outward appearance alone.

Published studies have described several named animals from the Scottish Romer’s Gap localities, including Aytonerpeton, Diploradus and Ossirarus from Burnmouth, and Koilops and other forms from the Whiteadder area. Their importance lies in the range of anatomy and relationships they reveal. The picture is of diversity, rather than a single creature standing for an entire stage of evolution.

Water remained central to their world. Having limbs does not automatically mean an animal spent its life walking confidently over dry ground. Some early limbed vertebrates remained strongly aquatic; others possessed combinations of features relevant to movement on land. Their fossils help researchers investigate that variation, rather than fitting every animal onto a simple ladder from fish to us.

Nor were vertebrates the first life to occupy land. Plants and invertebrates were already part of terrestrial ecosystems. Millipede fossils from this early Carboniferous interval add another strand to the story. The developing land communities contained more than their most eye-catching four-limbed members.

Fish are important too, including lungfish and other groups found in these deposits. Their remains remind us that the transition towards land unfolded within thriving aquatic worlds. The river margin was not an empty stage awaiting one evolutionary breakthrough. It was already a place of feeding, competition, shelter and change.

Why the Mud Matters as Much as the Bones

A fossil removed from its setting can look like an isolated treasure. For science, the setting is often part of the treasure. The grain size of sediment, the shape of a bed, traces of an ancient soil and the organisms found alongside a bone can help reconstruct the circumstances in which it was buried.

Some Burnmouth material has been studied as an assemblage associated with a sediment flow across a vegetated floodplain. Such a deposit can bring remains together from the surrounding environment. It offers information about a community, while also requiring care: animals preserved beside one another may have been transported before burial.

This is why responsible fossil research is more than collecting attractive objects. Recording the layer and location can preserve information that would otherwise be lost. A fragment whose exact position is known may be more useful than a better-looking specimen with no record of where it came from.

There is also a broader lesson in the Borders discoveries. When researchers investigated suitable rocks carefully, the supposedly sparse interval began to yield more life. A gap in knowledge can narrow through fieldwork, patient preparation and new ways of bringing evidence together. The landscape still had stories to offer; people had to learn where and how to read them.

Siccar Point and the Scale of Time

Along the Berwickshire coast, Siccar Point provides another way into this vast timescale. In 1788, James Hutton visited with John Playfair and James Hall. The meeting of steeply tilted older rocks and younger beds above them offered a powerful demonstration of a long sequence of events.

The older sediments had been deposited, turned into rock, tilted and eroded before the younger material accumulated over them. The contact between the two is an unconformity: a surface representing missing time and intervening change. It is not an exhibit someone arranged to explain geology. The landscape itself supplies the evidence.

Siccar Point does not contain the whole fossil story described here, but it helps us grasp the time needed for it. Rocks can record deposition and movement, while an eroded surface can mark a chapter that is no longer present. The Earth’s history includes what survives and what has been taken away.

That thought transforms a drive through the region. In our Talla Reservoir story, a road and a body of water provide a familiar encounter with the Borders landscape. Geology invites another layer of attention: what the hills are made from, why they stand where they do and how often the scenery has been remade before reaching its present form.

So Where Do the Dinosaurs Fit?

Dinosaurs arrived much later, roughly 230 million years ago. By then, the organisms preserved in the Borders’ early Carboniferous deposits belonged to a distant past, and the older ocean rocks were older still. The age of the available rock is therefore central to the original question.

Scotland’s important dinosaur discoveries come from suitable younger rocks elsewhere, especially on Skye. Middle Jurassic deposits there have preserved bones and footprints. Eigg has also yielded dinosaur bone. In 2025, researchers revealed Elgol dinosaur material from Skye, a significant partial skeleton interpreted as a Jurassic ornithopod.

Those discoveries are exciting, but they do not make every Scottish rock a potential dinosaur-bearing layer. Much of the exposed Borders bedrock was formed too early. Searching it for dinosaurs would mean searching a chapter written before those animals existed.

That does not settle every question about what lived across this part of the world during the dinosaur era. Landscapes change, rocks are removed and the record is incomplete. It does explain why the fossils we can study here lead us towards other lost worlds. The Borders does not need a dinosaur skeleton to have an extraordinary place in the history of prehistoric life.

Ice, Rivers and the Landscape We Recognise

After all these ancient chapters, the familiar shape of the Borders still lay far in the future. During the Ice Age, moving ice reshaped the region, scouring valleys, transporting material and leaving deposits as it withdrew. The Tweed basin and the uplands preserve evidence of different glacial processes.

Across parts of the Merse, rounded landforms called drumlins record movement beneath ice. In the hills, glacial erosion helped produce the strong valley forms that now frame roads, lochs and settlements. Later rivers worked through the deposits and continued changing the surface.

This is why the age of the rock and the age of the visible landscape are different questions. A valley can be carved into stone that formed hundreds of millions of years earlier. The rock supplies the material; later processes give much of the scenery its present shape.

Today the Tweed carries a living world of its own. Our films Winter Wildlife on the River Tweed and Salmon Jumping near Galashiels bring us back to that present-day river. Watching them after following the fossil story adds a different perspective. Water remains central to the region, but its inhabitants, course and surroundings have changed beyond recognition.

Looking Again at the Ground Beneath Us

You can enjoy this story without collecting anything. Look at the bands in an exposed rock face from a safe public viewpoint. Notice how a burn cuts through the hillside, or how the coast reveals layers otherwise hidden beneath soil. Visit museums, follow interpreted geological sites and let the landscape become something you can begin to read.

Famous scientific exposures deserve particular care. Dob’s Linn is a reference locality, not a supply of souvenirs. Riverbanks and coastal cliffs can also be dangerous, and important fossil sites may require permission or specialist access. Leave rocks in place where appropriate, keep away from unstable ground and use established routes rather than turning a visit into an excavation.

The reward is not necessarily something to carry home. It can be a change in the way you see a place you thought you knew. A hill beside Hawick becomes the remains of an ancient marine setting. The Whiteadder becomes a window into a tropical world. A quiet coastal exposure becomes part of a discussion about how vertebrates established themselves on land.

We are used to discovering the Borders through castles, lost towns such as Roxburgh, ruined abbeys and stories passed between generations. Those remain compelling. Beneath them sits another history, immeasurably older, which gives the region a different kind of significance.

Before the dinosaurs, there was an ocean here. Later came wetlands, rivers and animals whose fossils are helping scientists understand a great evolutionary transition. Then came further ages of change, the ice and eventually the human Borders. Stand beside the Tweed or look across the hills, and all you see is the latest landscape in a very long succession of lost worlds.