Scientists investigate the origin of a mysterious hidden mangrove ecosystem found in the heart of the Yucatan Peninsula in Mexico. Unlike other mangrove ecosystems that thrive in coastal waters, these isolated mangroves have developed characteristics that made it possible for them to flourish 124 miles (200 kilometers) away from the nearest ocean.

According to Live Science, the ancient mangrove ecosystem's origin is an ecological enigma to scientists before. But the recent study from multidisciplinary researchers revealed that this "lost world" has been thriving for 125,000 years, which began when sea levels were higher and when the ocean covered much of the region.

Analyzing Mangrove DNA to Know When It Ends Up Being Isolated

Red mangroves (Rhizophora mangle) typically only survive in salt water along the coastlines. That is why seeing them grow in the freshwater San Pedro River baffled scientists. But somehow they have adapted to live exclusively in this environment and managed to flourish in the last 125,000 years.

Study lead author Octavio Aburto-Oropeza, a marine ecologist from Scripps Institution of Oceanography at the University of California, San Diego, said in a news release via EurekAlert! examining this unique ecosystem that has been trapped for more than 100,000 years is like finding a lost world.

Although the San Pedro mangrove ecosystem has only been recently studied, locals have been enjoying it for generations despite not knowing exactly how it got there. So, researchers analyzed the DNA in mangrove trees to see how different they are compared to other mangrove ecosystems.

Evolutionary geneticist Richard Nichols from Queen Mary University in London said that counting the number of differences between two genomes could yield an estimated number of generations since those two genomes shared an ancestor. He added that the most recent common ancestors of the two genomes must pre-date the period of isolation.

In the San Pedro mangrove's case, the team determined that the mangrove has been isolated 125,00 years ago but that area must have also been a coastline when sea levels were higher. However, modern-day levels left it trapped inland and forced it to adapt to freshwater conditions in the river.

ALSO READ: Mangroves in Danger: Lack of Invertebrates, Other Species That Threaten Plant Populations

Past Climate Change Affected Last Interglacial Period

According to SciTech Daily, the study highlights the extensive impacts of the past climate change on the landscape of Mexico tropics during the last interglacial period when much of the Gulf of Mexico coastal lowlands were underwater. More so, the study's findings open opportunities to understand future scenarios when sea levels rise as a result of worsening climate change.

Botanist Carlos Burelo from the Universidad Juárez Autónoma de Tabasco and a native of the region said that these mangroves served as a playground for them as a kid where they would fish and play.

His work and biodiversity surveys established a solid foundation for the study, which is turned into a documentation of the mangrove ecosystem shown in the award-winning short film "Memories of the Future: the modern discovery of a relict ecosystem."

RELATED ARTICLE: One-fifth of Mangroves in the World Already Perished and Could Be Totally Gone by 2050 Due to Rising Sea Levels

Check out more news and information on Mangroves in Science Times.