Protozoan changes the way of looking at evolution

On the diving area of ​​the Bahamas, Mikhail V. Matz of the University of Texas, Austin and some colleagues are looking for big, glowing eyes to adapt to the dark.

However, when diving right above the seabed, the team was attracted by hundreds of exotic grape-sized globes. Each fruit is at the end of the zigzag lines in the seabed mud. Clearly, these fruits have left those marks.

The team collected the specimen and identified it as a giant single-celled organism, Gromia sphaerica, each of which is just a large cell with an organic shell.When removing sediment, this shell is like grape skin, but softer.

Above: close-up of Gromia sphaerica, the size of a grape. Below: Gromia sphaerica is creating traces on the sea floor. This trace is similar to the ancient fossil trail. Scientists have suggested that the fossil trace is a multicellular organism to cross, possibly a worm. But now they were wondering whether to fade Gromia sphaerica before that left this fossil trail. (Photo: Mikhail Matz, University of Texas, Ausin / NOAA / HBOI)

Surprisingly, this creature trace left on the Bahamas seabed is similar to the lines found on sedimentary rock formed 1.8 billion years ago. Ancient trace lines are the only evidence that multicellular organisms, symmetrical animals, such as worms, have evolved very early in Earth's history.

Matz's discovery (about the trail of going to G. sphaerica) suggests that unicellular animals may have left that fossil trace, not higher-order organisms.Other evidence of multicellular and symmetrical organisms occurs in fossils dating to 580 million years and 542 million years.

G. sphaerica is a prosthetic, an ancient group of single-celled organisms. Matz is planning more research on this animal.

The findings are published in curren biology magazine.