A fossil found in a billion-year-old style from the Scottish Highlands may represent a missing link between unicellular organisms and multilingual animals.
If so, it could fill some significant gaps in our knowledge of the history of life. Professor Charles Wellman of the University of Sheffield said in a statement, “The origins of complex multidisciplinary and the origins of the fauna are considered two important events in the history of Earth’s life, and our discovery sheds new light on both.”
“We found a primitive spherical organism made up of a combination of two distinct cell structures, the first step towards a complex perennial structure, never described before in the fossil record,” Wellman said. Wellman and co-workers named a species called Bicellum brasieri in current biology, the genus named its two types of cells a node. The species name is revered by co-author Martin brasieri, who died between discovery and publication.
The authors think that Bicellum was probably a holozoan, not algae. Holozoans form broad branches of trees, above which the animals are more closely related to us than just a stalk, many unicellular organisms, or even farther relatives, such as plants. “The mature form of biceps is composed of a stiff, rounded ball of stiff, packed cells … somehow enclosed in a longer, sausage-shaped cell,” the paper notes. Like the whole object, the inner cells are almost round, and span 2-3-meters.
The outer cells are somewhat compressed but are usually three to four times longer. The whole balls average 28.5μm (0.001 in), the thickness of a particularly fine human hair. “However,” the paper continues; “Two populations … shows the size of a mixed cell, which we assume indicates the faint development of elongated cells that migrate to the perimeter of the cell mass”, “Was created.
If Bicellum does not teach us anything else, we can learn a lot from the rock we have received. Their age tells us that the first wave of polygamy occurred at least a billion years ago, when their composition indicates that it occurred in freshwater lakes instead of oceans.
Time can help solve the question of whether atmospheric oxygen was a necessary condition for the animal to develop. Nevertheless, the discovery may answer the fundamental question of how something more complex than a single cell could evolve.
