Scientists have uncovered “extraordinary” evidence of what is thought to be the oldest deliberate human burial in Africa, dating to 78,000 years ago.

The remains of a three-year-old child were unearthed at Panga ya Saidi – a cave on the Kenyan coast, with “astonishingly preserved” bone arrangements.

The researchers said their findings, published in the journal Nature, are the earliest known evidence of a ceremonial act of burial by modern humans in Africa and offer new insight into how our ancestors treated their dead.

Professor Nicole Boivin, director of the department of archaeology at the Max Planck Institute for the Science of Human History in Germany, said: “As soon as we first visited Panga ya Saidi, we knew that it was special.

“The site is truly one of a kind.

“Repeated seasons of excavation at Panga ya Saidi have now helped to establish it as a key type site for the East African coast, with an extraordinary 78,000-year record of early human cultural, technological and symbolic activities.”

Portions of the child’s bones were first found in 2013 but it was not until 2017 the remains were fully exposed.

They were too delicate to study in the field so the researchers took the bones to laboratories in Spain to examine them.

Analysis of the two teeth found in the remains revealed they belonged to a child, nicknamed Mtoto, between two-and-a-half and three years old.

Scientists at the National Research Center on Human Evolution (CENIEH) in Burgos, Spain, then began the painstaking task of uncovering the rest of the remains, which included parts of the skull and face, with unerupted teeth in the lower jawbone, as well as the spine and the ribs.

Professor Maria Martinon-Torres, director at CENIEH, said: “The articulation of the spine and the ribs was also astonishingly preserved, even conserving the curvature of the thorax cage, suggesting that it was an undisturbed burial and that the decomposition of the body took place right in the pit where the bones were found.”

Based on a microscopic analysis of the bones and surrounding soil, the researchers said the body was rapidly covered after burial – meaning Mtoto was intentionally buried shortly after death.

Arrangement of the bones show the child lying on the right side with knees drawn towards the chest, while the position and collapse of the skull suggests the youngster’s head was resting on a perishable support – such as a pillow, according to Prof Martinon-Torres.

The researchers said these findings point to “a complex ritual that likely required the active participation of many members of the child’s community”.

While remains uncovered at the Panga ya Saidi cave represent the earliest evidence of intentional burial in Africa, burials in Europa and Asia go back as far as 120,000 years – involving Neanderthals as well as modern humans.

The researchers said that differences in mortuary practices could be one of the reasons why the evidence of burials in Africa remains comparatively scarce and elusive.

Professor Michael Petraglia, also of the Max Planck Institute, said: “The Panga ya Saidi burial shows that inhumation of the dead is a cultural practice shared by Homo sapiens and Neanderthals.

“This find opens up questions about the origin and evolution of mortuary practices between two closely related human species, and the degree to which our behaviours and emotions differ from one another.”