What Was The First Animal, The Sponge Or The Comb Jelly?

comb jelly

Scientists have been wondering what came first, the sea sponge or the comb jelly?

For almost a decade, scientists have been debating as to what was the first animal to evolve on Earth. The main competitors are the simple sea sponge versus the comb jelly, an ocean predator species. Now, a new research claims that this latter deserves the title and that it also has proof to support it.

This latest research was carried out by Vanderbilt University in Tennessee researchers led by Antonis Rokas. They published their results in the Nature Ecology and Evolution journal.

The Comb Jelly May Quite Possibly Be The First Animal To Have Evolved On Earth

For most of a century, research considered the sea sponge as being the earliest life form. It achieved this title mostly thanks to its structural simplicity. However, over the recent decades, new studies based on genetic sequencing claimed that comb jellies are a better candidate for this place.

As such, Rokas and his team set out to determine both the earliest form of animal life, and determine the reason behind this controversy. In most cases, genetic sequencing offers exact answers while this time around, it raised more questions.

For this study, the researchers took a closer look at the details of some of the genes shared across the investigated species. More exactly:

“The trick is to examine the gene sequences from different organisms to figure out who they identify as their closest relatives.”

In doing so, the team found that the comb jelly is more likely to have diverged first. The team determined this as the jelly shared more genes with the other species when compared to the sea sponge.

Also, the team determined found that some “strongly opinionated genes” can also lead to confusing results in the statistical analysis used for phylogenetic data. As such, a correction of their influence should help lead to quicker, easier fixes for any potential future controversies.

Image Source: Flickr

About June Harris

June was born and raised in Ligonier, a small historic town in Pennsylvania. She befriended TV cameras at an early age when she was selected to feature in a local TV series for children. Her passion for entertainment grew bigger after June was named Miss Pennsylvania at 16 years old. She was co-opted in various projects ever since and is now a strong promoter of fitness and health activities.