The first species on Earth had certain real estate preferences

Posted on 15 May, 2023 by benyamin chahkandi

summary: For the first time, new research reveals that some of the earliest species on Earth managed to be fussy about where they resided despite not having body components that allowed for movement.

These curiously shaped soft-bodied sea critters lived during the Ediacaran Period, around 550 million years ago. They have long been regarded as mysterious by researchers.

The study's lead author and graduate student in paleontology at the University of California, Riverside, Phillip C. Boan, said, "It's not like researching dinosaurs, which are linked to birds we can see today. We're still figuring out the basics of these animals' lives, such how they reproduced and what they ate, because they have no current offspring. 
To better understand where the animals lived in the sea, researchers focused on one particular research endeavor.
 

In addition, compared to modern marine ecosystems, the ancient sea was a largely alien world. It was dominated by a mat of bacteria and other organic things on the ocean floor. Furthermore, predatory species were rare.

The discovery of an animal that lived quite similarly to modern-day barnacles startled the researchers given the foreign nature of Ediacaran Earth. Obamus coronatus, named after the last U.S. president, chose to live on particular regions of the sea floor in the company of other Obamus, according to a recent Paleobiology research.

The animal was "shaped like a French cruller donut with ribbons on top," according to Boan, and had an average diameter of around half an inch. It did not voluntarily move, and most likely spent its entire life embedded in its preferred spot on the sea floor.

"When we consider the oldest animals, you might not anticipate them to have such discerning tastes. However, Obamus only lives in areas with dense mats, and for something so ancient, it has a rather complex manner of subsisting, according to Mary Droser, a distinguished professor of paleontology at UCR and a research co-author.

In 2018, Barack Obama's love of science inspired Droser to rename his lab the Obamus. It was found by her team at a fossil site in the Australian Outback known as Nilpena Ediacara National Park, which is known for its exceptionally well-preserved fossils.
 

The Ediacaran sea floor at Nilpena was covered in layers of silt by a succession of storms, which helped preserve sandstone impressions of entire animal populations that coexisted there. This allows us to piece together entire ecosystems, according to Droser. Instead of staring at a single animal in a fish tank, viewing them is like snorkeling around on the ancient sea floor.

The research team chose three species that were relatively common at Nilpena and looked at their global distribution for this endeavor.

Tribrachidium and Rugoconites, the other two species, are also static creatures without modern offspring. According to Boan, "they are tri-radially symmetrical, like the Mercedes Benz logo." And like Obamus, they would have spent their entire lives submerged in the ocean.

These other two creatures had a diverse distribution. Occasionally, but not always, they may be discovered coexisting with other organisms that were similar to themselves. Obamus, though, made it obvious what he preferred.

This is actually the first instance of a habitat-selective Ediacaran species, according to Boan. It's also the first instance of a macroscopic animal doing this. But how did they travel to their destination? We don't yet know the answer to this query.

According to the research team's hypothesis, Obamus were probably driven by the need to procreate.

Particularly for creatures like these, there aren't many reproductive techniques, according to Droser. Today, there are more strategies, and they are more complex. However, they were still being utilized today.

The larva of Obamus probably propagated the species by choosing areas with dense microbial mats and close to other Obamus. We don't fully understand how Obamus children dispersed, but we do know that they were highly particular about where they chose to live, according to Boan.

Researchers might gain insight into how life might arise on another planet by developing a deeper grasp of how life on Earth evolved over time. Droser's lab is therefore supported by NASA's Exobiology program.

This is our window into the formation of a complex ecosystem, according to Boan. "We only have Earth, so when we consider life anywhere in the universe, we must consider every aspect of its past."
 

Source: www.sciencedaily.com/releases/2023/05/230509122052.htm