A new ancient miniature whale species has been identified by researchers.
An international team of scientists made the “ground-breaking” discovery of a new species of extinct whale, Tutcetus rayanensis, that lived in the ancient sea covering present-day Egypt some 41 million years ago.
With an estimated length of 2.5 metres (about 8ft) and a body mass of approximately 187 kilograms (about 30st), experts suggest Tutcetus is the smallest known basilosaurid whale to date.
It is also one of the oldest records of that family from Africa.
Despite its small size, Tutcetus has provided unprecedented insights into the history of early whales.
Researchers suggest that the basilosauridae, a group of extinct, fully aquatic whales, represent a crucial stage in whale evolution, as they transitioned from land to sea.
They developed fish-like characteristics, such as a streamlined body, a strong tail, flippers, and a tail fin, and had hind limbs visible enough to be recognised as legs, which were not used for walking but possibly for mating.
Hesham Sallam, a Professor of Vertebrate Palaeontology at the American University in Cairo, founder of the Mansoura University Vertebrate Palaeontology Centre, was the leader of the project.
He said: “Whales’ evolution from land-dwelling animals to beautiful marine creatures embodies the marvellous adventurous journey of life.
“Tutcetus is a remarkable discovery that documents one of the first phases of the transition to a fully aquatic lifestyle that took place in that journey.”
The new discovery was made in the middle Eocene rocks and it helps to illuminate the picture of early whale evolution in Africa.
The new whale’s name draws inspiration from both Egyptian history and the location where the specimen was found.
Tutcetus, combines “Tut” – referring to the famous Egyptian Pharaoh Tutankhamun – and “cetus,” Greek for whale, highlighting the specimen’s small size and subadult status.
The name is also a nod to the discovery of the king’s tomb a century ago and coincides with the impending opening of the Grand Egyptian Museum in Giza.
The species name, rayanensis, refers to the Wadi El-Rayan protected area in Fayum where the specimen was found.
The specimen that researchers found consists of a skull, jaws, hyoid bone, and the atlas vertebra of a small-sized, subadult basilosaurid whale which is embedded in an intensively compacted limestone block.
Sanaa El-Sayed, a PhD student at University of Michigan and a member of Sallam Lab, and a co-author of the study, said: “The relatively small size of Tutcetus is either primitive retention or could be linked to the global warming event known as the Late Lutetian Thermal Maximum (LLTM).
“This ground-breaking discovery sheds light on the early evolution of whales and their transition to aquatic life.”
Through detailed analyses of Tutcetus’s teeth and bones, and CT scans, the team was able to reconstruct the growth and development pattern of this species.
The findings are published in the Communications Biology journal.