Scientists Say Humans Still Carry Genes from Ancient Sea Monsters That Lived 500 Million Years Ago

Before the mighty dinosaurs who dominated the Earth for 165 million years, we have these ancient sea creatures from the Ediacaran Period, approximately 635 to 541 million years ago. What is shocking about them is that scientists have found out that after all this time, we still share some of their genes.

Ancient Sea Creatures and Their Unexpected Legacy

The sea monsters or creatures from the Ediacaran Period don’t have any heads, limbs, or eyes; they just floated around in the ocean. Today, researchers from the Royal Society Publishing have found out that some of our crucial genes for development are also present in them.

Most of these sea creatures from the Ediacaran period look like leaves, or the majority are just flat in body, in different shapes. To survive, they just float around the waters or rub themselves on the deep ocean floor to look for anything to eat. Ocean waters at the time are believed to be rich in food sources, including algae and bacteria.

Even back then, they already had the developmental genes that would be passed on to us. Those genes are what’s likely structured the bodies of modern animals, and that includes us. Some examples are things like the symmetry of our bodies, sensory organs, and our immune systems.

Source: Royal Society Publishing

Shared Genetic Heritage

The Ediacaran Period: Glimpses of the Earth's Earliest Animals

The Ediacaran is a period in history when life was just beginning to take form. So, most of the ancient sea creatures almost look alike or have some shared traits, like the lack of heads and limbs, which will most likely develop after a few more million years.

Not only humans and modern animals, but also some of the planet’s earliest multicellular organisms have the same genes as these long-extinct marine animals.

The study focused on four of the sea creatures that existed in this period, namely, Dickinsonia, Kimberella, Tribrachidium, and Ikaria. Their remains were extracted from the Australian outback, providing a very rare opportunity to look back into the past.

Source: Science Times

Four Representative Ediacaran Species

Here is a breakdown of what the study found in each of these 4 representatives of the Ediacaran period:

Dickinsonia: The study indicates that Dickinsonia, which is characterized by an oval, ribbed body, is a very mobile creature, already exhibited bilateral symmetry. That is a fundamental trait in most modern animals you see today.

Kimberella: It is a mollusk-like organism, which has an oval-shaped body with distinct front and back, and is believed to have a feeding structure, most likely a proboscis, used to graze on microbial mats. This is a sign that it already has the formula for even more complex organs.

Tribrachidium: It is a sea creature that looks like a pinwheel, a very circular one. Unlike the other sea monsters on this list, Tribrachidium did not exhibit a bilateral symmetry body construction. This suggests that even then, there is already diversity in life, to find out which works the best, and is likely to survive the next evolutionary stage.

Ikaria: Ikaria wariootia is one of the oldest living creatures to have been found exhibiting a bilateral body, which means it has a front and back. It looks like a very simple form of life that resembles present-day worms. The presence of such a body type over 500 million years ago tells us that during that period, bilateral symmetry and organ development were already in the works, one that will carry on up to this day.

Scientists previously thought that at that period, life was not complex at all, but these creatures signify that even then, the foundations of the next evolution of life were beginning to emerge, such as body symmetry, movement, and internal organization.

Source: Live Science

Implications for Human Evolution

Ancient Creatures Share Genes With Humans | WION Podcast

These findings provide insights into how our biological body and evolution are understood. That even then, life is already creating the formula that will carry on for hundreds of millions of years in the future.

This basically just challenges our previous thought of how early evolutionary complex body structures and functions were developed. We are all a product of the conclusion that these sea creatures arrived back then on which type of body, and which genes are most helpful to survive.

Author's Final Thoughts

We often perceive creatures that lived on Earth much earlier than us are completely different from the modern organisms of today, including humans. That is actually not true, and this study proves that the formula and genetic blueprint of life were already on the move over 500 million years ago, and that part of it still lives within each and every one of us.

Read more: Two 7,000-Year-Old Mummies Found — And They Don’t Share DNA With Modern Humans

References & Further Reading

Putnam, N. H., et al. (2007). Sea anemone genome reveals ancestral eumetazoan gene repertoire and genomic organization. Science. https://doi.org/10.1126/science.1139158

Putnam, N. H., et al. (2008). The amphioxus genome and the evolution of the chordate karyotype. Nature. https://doi.org/10.1038/nature06967

Venkatesh, B., et al. (2014). Elephant shark genome provides unique insights into gnathostome evolution. Nature. https://www.nature.com/articles/nature12826

Simakov, O., et al. (2015). Hemichordate genomes and deuterostome origins. Nature. https://www.nature.com/articles/nature16150

Dehal, P., & Boore, J. L. (2005). Two rounds of whole genome duplication in the ancestral vertebrate. PLoS Biology. https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.0030314

Smith, J. J., et al. (2018). The sea lamprey germline genome provides insights into programmed genome rearrangement and vertebrate evolution. Nature Genetics. https://www.nature.com/articles/s41588-017-0036-1