They see the eggs and sperm of spawning coral floating past their boat minutes later. They take the blobs of fishy smell and place them in test tubes.

The Darwinian experiment aims to accelerate coral’s evolution to create “super corals”, which can better withstand global warming.

The researchers have been testing their theories for the past five year. They are now ready to plant corals from the lab in the ocean to test their survival in natural environments.

“Assisted evolution began out as this crazy idea that you could actually make something change and allow it to survive better because its changing,” Kira Hughes, a University of Hawaii researcher, said.

SPEEDING UP NATURE

Three methods were tested to make corals more resilient by researchers:

— Selective breeding to pass on desirable traits from parents.

— This is a method of exposing corals to heat at increasing temperatures.

— Modifying the algae that provides corals with essential nutrients.

Hughes stated that all the methods have been successful in the laboratory.

Hughes stated that the planet’s rapid warming is forcing scientists to worry. She stated that “we have to intervene to make coral reefs survive into the future.”

Coral releases its symbiotic alga that provides nutrients and vibrant colors when the ocean temperature rises. The coral can become white, a process known as bleaching. It can also quickly become sick and eventually die.

Over a decade, corals have survived bleaching and have survived the death of others on the same reef.

Researchers are now focusing their efforts on the survivors who can withstand heat to improve their heat tolerance. They found that selective breeding was the best way to save Hawaii’s coral reefs.

Crawford Drury is the chief scientist at Hawaii’s Coral Resilience Lab. He stated that while there are many stressors to corals around the world, increasing temperatures are most dangerous. “So that’s where our focus is, working with parents who are thermally tolerant.”

A UNIQUE IDEA

Ruth Gates, the founder of the resilience lab, and Madeleine van Oppen, of the Australian Institute of Marine Science, published a paper in 2015 on assisted evolution during one of world’s worst bleaching episodes.

Scientists suggested that corals be brought into a laboratory to allow them to evolve into heat-tolerant animals. Paul Allen, Microsoft’s co-founder and chief executive officer, was attracted to the idea. His foundation continues to support the program.

Gates stated that he had given the experiences to (coral) to increase their survival chances in a 2015 interview to The Associated Press.

Gates, who was diagnosed with brain cancer in 2018, died from the disease. She also stated that she wanted people to understand how “intimately” reef health is intertwined and connected with human health.

Coral reefs are often called the “rainforests of the ocean”. They provide food and protection for marine life, as well as jobs and medicine for illnesses like arthritis, cancer, and Alzheimer’s disease.

According to a recent report by the National Oceanic and Atmospheric Administration and others, bleaching events pose the greatest threat to coral reefs around the globe. Researchers found that the world lost approximately 14% of its coral between 2009-2018.

When assisted evolution was first proposed, it wasn’t widely accepted.

Van Oppen stated that there are concerns about genetic diversity loss and critics who claim scientists are “playing gods”, by manipulating the reef.

Van Oppen stated, “Well, you know that (humans have) already intervened with coral reefs for very long periods.” “All that we are trying to do is repair the damage.”

She said that researchers are not trying to alter genes or create anything unnatural. They are simply nudging what might already be happening in the ocean. “We really are focusing on the smallest scale possible in order to preserve and enhance what is already here.”

MILLIONS OF YEARS AGO IN MAKING

There are still questions.

Steve Palumbi, a Stanford University professor and marine biologist, said that there are many reasons corals don’t bleach. “Just because a coral isn’t bleaching in field or lab doesn’t necessarily mean that it is heat-tolerant.”

The life span of corals is approximately 250 million years. However, their genetic code remains a mystery.

Palumbi stated that this is not the first occasion any coral has been exposed to heat. “The fact that corals aren’t heat-resistant tells us… that it has some disadvantages.” They would all be resistant to heat if they didn’t have a disadvantage.

Palumbi believes that assisted evolution has a place in coral management plans, because “reefs around the world are in desperate and desperate, desperate trouble.”

This project has received broad support and sparked research all over the globe. Researchers in Germany, Saudi Arabia, Germany, and other countries are also doing coral resilience research. The U.S. government supports the effort.

Jennifer Koss (director of NOAA’s Coral Reef Conservation Program) stated that assisted evolution is “really impressive” and “very consistent with a study we conducted with The National Academies of Sciences.”

Koss stated, “We asked them for the most cutting-edge science that was really focused on innovative interventions in coral Reef management.” “And this assisted gene flow fits right into that.”

MAJOR HURDLES

There are still many serious problems.

Scalability is one. It will be difficult to get lab-bred corals into the ocean, and for them to survive, due to the fact that reintroduction must occur at a local level in order to prevent any harmful biological material being brought from one area to another.

James Guest is a UK coral ecologist and leads a project that shows selectively bred corals can not only survive in warmer waters but can also be successfully restored on a large scale.

Guest stated, “It’s great that we can do all of this stuff in the laboratory. But we have to prove that we can get very large quantities out onto the reef in an economically-sound way.”

Scientists are currently testing delivery methods such as sending ships to transport young corals into oceans and using small robots underwater to plant them.

Nobody is suggesting that assisted evolution will save the reefs. This idea is just one of many measures that are available to help reefs get cooler.

Planting stronger corals has the advantage that they will naturally spread their traits after a few generations.

The Hawaii scientists will continue to place selectedly bred corals back into Kaneohe Bay over the next few years and watch their behavior. Van Oppen and her collaborators have already placed some hybrid corals, where eggs from one species are fertilized with the sperm of the other, back onto the Great Barrier Reef.

Scientists say that the world’s oceans are continuing to heat up and they need to stop it from destroying reefs.

Drury from Hawaii said that “all the work we’re going to do here” won’t make any difference if climate change isn’t addressed on a global and systematic scale.

“So, in essence, we are trying to buy time.”