The First Humans in Britain

These footprints are the oldest known outside of Africa and they were made by early humans that occupied an area in the north of present-day Norfolk around 900,000 years ago. The footprints were found on the coast just outside of Happisburgh (pronounced Haze-bruh) and were revealed by the sea, as it eroded the younger sediment away. And just like our own footsteps in the sand, the tide swiftly took them away again almost one million years after they were left by these early Britons. Luckily, they were captured in 3D images and recorded before the waves destroyed them. Here's a link to a video of the team recording the prints after their discovery in May 2013, made by the Natural History Museum and available on the Channel 4 website.

The fossilised footprints were found in a sediment layer of the Cromer Forrest bed, which consists of river gravels, estuary and floodplain sediments found all along the northern Norfolk coast, deposited between 2 to 0.5 million years ago during the Cromerian interglacial of the Pleistocene, before the big Anglian ice age set in. More evidence of human occupation from that time comes in the shape of a handaxe and other flint tools found in the Forest bed sediments near Happisburgh.

Outcrops of the Forrest bed can be found all along the north Norfolk coast. In some places, such as the cliff section shown here near the town of West Runton, it is about 2 meters thick.

Here, these Freshwater bed deposits rest on the slightly older Wroxham crag sediments (2 million ya) and 70-80 million year old Cretaceous deposits, and are covered by ice age deposits of the Anglian glaciation (~500,000 years ago).

The thick layer of organic-rich mud was deposited by a medium sized river and is full of fossils ranging from tiny snail shells and bones of small mammals all the way up to horse, hippopotamus, rhinoceros and mammoth bones. One of the most famous fossils from this bed is that of the West Runton Elephant, a very well-preserved skeleton of a Steppe Mammoth (Mammuthus trogontherii).

The image below shows a reconstruction of this river landscape, at some point during the Cromerian warm period. Based on the fossils found in the Forest bed deposits, early humans found themselves surrounded by big game such as rhino, hippo and steppe mammoth but also moose, wild boar and deer. They would have also had to fight off some top predators/scavengers such as bears and hyenas to get to their food. Human occupation during this period may have not been continuous, as the sediments record cyclic temperature changes, with rising sea levels when polar ice caps shrank during warm periods and forest vegetation making way for open grassy habitats during colder spells. Studies of pollen grains trapped in the sediments show a similar picture, indicating the presence of pine-birch forest at the start of this interglacial, followed by a period dominated by oaks, which in turn was replaced by a conifer forest, changes indicating that the climate varied from cool to temperate and to cool again.

Over the last 250 years, thousands of fossil mammals have been discovered, exposed due to coastal erosion. I regularly visit this region because of my interest in flint deposits and Cretaceous fossils and in particular because this area is rich in fossilised echinoids (sea urchins).

During a recent visit with the family, in addition to the numerous cretaceous urchins and sponges, the children discovered several mammal fossils in the ironstone flint concretions associated with the forest bed.

The fossils include a bear patella (knee cap), and three coprolites (fossilised droppings). The bear patella, shows features similar to that of a cave bear (Ursus spelaeus), also shown for comparison, and remains of a relative of this extinct bear, Ursus deningeri, have been found in the Forest bed deposits. Standing close to 3.5 meters tall, while upright, and weighing up to 1,000 kg, this was a creature early humans would have definitely given a wide birth. The ironstone fossilisation has preserved some of its very delicate features, including the patellar tendon that attaches it to the tibia (shin bone).

Signs of pathology have also been preserved, indicating that this bear suffered from severe chondromalacia patellae or ‘runners knee’ later in life, which may have been caused by overuse, fracture or an infection and must have been very painful. With some luck early humans may have been able to outrun this limping beast.

Fossilised droppings have been found during the excavation of the West Runton Elephant, attributed to the spotted hyaena (Crocuta crocuta), because of their distinctive shape. Two of the ironstone coprolites presented here resemble wild boar droppings, especially the distinctive bands on one of them are very similar to those found today. The coprolite on the right resembles those found in Madagascar, thought to be turtle coprolites.

Although some ironstone 'coprolites' are thought to be pseudo fossils of 'diagenetic' origin (formed through chemical processes after deposition), the fossils shown above clearly are of organic origin, delicately preserved in ferruginous streams, similar to the present-day example shown below.

Although no fossils have been found, it is believed that the footprints left in the Forest bed sediments in Cromerian Norfolk are those of Homo antecessor. This species of early human pioneers is known from fossils of a similar age to the Forest bed sediments, found in the Atapuerca Mountains of Spain around 800,000 years ago.

The Forest bed deposits may still give up more of their secrets in the future, perhaps revealing further clues as to the true identity of these early britons. Whilst coastal erosion presents us with a wealth of information about the environment they were living in, it has become a serious threat to the habitat of the people that currently live along the Norfolk coast. Although it is thought that the Norfolk cliffs have been eroding for over five thousand years due to increasing sea levels, future predictions of sea level rise and storm frequency due to climate change are likely to have a much more profound impact on this area.