A team of scientists, led by the University of Sheffield in the UK and Boston College in the USA, has found a microfossil that contains two distinct cell types and could be the earliest multicellular animal ever recorded.
The fossil reveals new insight into the transition of single-celled organisms to complex multicellular animals. Modern single-celled holozoa include the most basal living animals, the fossil discovered shows an organism that lies somewhere between single-cell and multicellular animals.
The fossil has been described and formally named Bicellum Brasieri in a new research paper published in Current Biology.
Professor Charles Wellman, one of the lead investigators of the research, from the University of Sheffield's Department of Animal and Plant Sciences, said: "The origins of complex multicellularity and the origin of animals are considered two of the most important events in the history of life on Earth, our discovery sheds new light on both of these.
[...] The fossil was found at Loch Torridon in the Northwest Scottish Highlands. Scientists were able to study the fossil due to its exceptional preservation, allowing them to analyze it at a cellular and subcellular level.
Paul K. Strother, Martin D. Brasier, David Wacey, et al. A possible billion-year-old holozoan with differentiated multicellularity [open] Current Biology (DOI: 10.1016/j.cub.2021.03.051)