The equivalent of a fossilized penis worm discovered with its brain
Generally, brain cells cannot be stored for long under natural decomposition conditions. However, recent studies by scientists from Peking University and of Bristol in England suggest that this is not an absolute rule. An embryo has been discovered and the latter presents traits never encountered before.
The approximately 500 million year old specimen is a cousin of the aquatic species Markuelia hunanensis (an ancient cousin of penis worms) and mud dragons (Kinorhyncha). Extensive observations made it possible to detect neuronsand other singular structures present in the embryo.
The sample was collected from a deposit named Wangcun Lagerstatte, in western Hunan, China. Nicholas Strausfeld, a professor in the Department of Neuroscience at the University of Arizona in Tucson, was the study’s lead author.
The first fossilized brain discovered to date
The researchers used a particle accelerator approximately 1,300 feet (400 meters) in diameter to visualize the structure of the fossil. By launching electrons at nearly the speed of light, a 3D model of the embryo was obtained. Thanks to the observations, the scientists were able to confirm that the fossilized structures present in the specimen are tissues, and not muscles or intestines.
Researchers believe that these are neurons that have been preserved under specific conditions. Through extensive studies, it has also been concluded that these brain cells are arranged in a ring around what would once have been the animal’s intestine. This is a very first for scientists since never before has nerve tissue been found in an Orsten-style fossil.
“The structure is a tissue that is not muscle and it is not gut either, I would say it is neurons. »
Nicholas Strausfeld, Regent Professor in the Department of Neuroscience at the University of Arizona
The fossil has unique characteristics
The analyzes carried out on the specimen reveal a quasi-preservation of its original anatomy. Scientists also noted the presence of a clear, organized structure within the head of the fossil. Said architecture was subsequently identified as being ring-shaped brain of the animal.
In addition, the fossil has distinctive features similar to muscle remains. Surprisingly, it contains traces of radically different nervous tissue. In reality, the specimen presents, at the same time at the level of its head and its tail, entirely separate mineralization cellsstructured and organized, very different from those present in all the other samples.