Giant shrimps as big as humans ruled the oceans 470 million years ago

By Mark Waghorn via SWNS

Giant shrimps as big as a human ruled the oceans 470 million years ago, according to new research.

The bizarre beasts were the 'Great White sharks' of their time and the stuff of nightmares.

They were up to 6ft five inches long - the same height as action hero Dwayne 'The Rock' Johnson.

Big bulging eyes on stalks and huge claws that ripped prey to shreds turned them into apex predators.

The primitive creatures are the ancestors of today's arthropods - creepy crawlies with jointed limbs.

Fossilized remains were unearthed at a site named Taichoute, part of a prehistoric graveyard in Morocco known as the 'Fezouata Biota.'

The animals were the product of a biological 'Big Bang' known as the Cambrian explosion when most animal groups emerged.

Lead author Dr. Farid Saleh, of the University of Lausanne, Switzerland, said: "Everything is new about this locality - its sedimentology, paleontology and even the preservation of fossils.

"It further highlights the importance of the Fezouata Biota in completing our understanding of past life on Earth."

At the time the area, now desert, was under a shallow ocean. Early evidence records numerous large 'free-swimming' arthropods.

Dr. Saleh said: "More research is needed to analyze these fragments, but based on previously described specimens, the giant arthropods could be up to 2m (6ft5in) long."

Imprints of exoskeletons encased in mud and sand are very different from others previously described from 50 miles away.

It opens new avenues for paleontological and ecological research, the international team state.

Co-author Dr. Xiaoya Ma, from the University of Exeter, said: "While the giant arthropods we discovered have not yet been fully identified, some may belong to previously described species of the Fezouata Biota, and some will certainly be new species.

"Nevertheless, their large size and free-swimming lifestyle suggest they played a unique role in these ecosystems."

The Fezouata Shale was recently selected as one of the 100 most important geological sites worldwide.

It is vital for understanding evolution during the Early Ordovician period, about 470 million years ago.

The fossils include mineralized shells. Some show soft parts such as internal organs - enabling anatomical investigation.

Repeated storms and waves buried whole communities - explaining the exceptional preservation. The mysterious species are dominated by fragments of giant arthropods.

Co-author Dr. Romain Vaucher, also from Lausanne, added: "Carcasses were transported to a relatively deep marine environment by underwater landslides, which contrasts with previous discoveries of carcass preservation in shallower settings, which were buried in place by storm deposits."

The findings were published in the journal Scientific Reports.