FSU researchers discover how ‘cryptic species’ respond differently to coral bleaching

FLORIDA STATE UNIVERSITY

Research News

IMAGE
IMAGE: THE CORAL REEF IN MOOREA BEFORE BLEACHING KILLED THE LARGER CORALS IN 2019. view more CREDIT: FSU COASTAL AND MARINE LABORATORY/SCOTT BURGESS

Certain brightly colored coral species dotting the seafloor may appear indistinguishable to many divers and snorkelers, but Florida State University researchers have found that these genetically diverse marine invertebrates vary in their response to ocean warming, a finding that has implications for the long-term health of coral reefs.

The researchers used molecular genetics to differentiate among corals that look nearly identical and to understand which species best coped with thermal stress. Their research was published in the journal Ecology.

“Being able to recognize the differences among these coral species that cannot be identified in the field — which are known as ‘cryptic species’ — will help us understand new ways for how coral reefs maintain resilience in the face of disturbance,” said Associate Professor of Biological Science Scott Burgess, the paper’s lead author.

The researchers were studying the coral ecosystem at the island of Moorea in French Polynesia when a coral bleaching event struck in 2019.

Corals get their color from algae that live in their tissues and with which they have a symbiotic relationship. But when corals are stressed — by high water temperature, for example — algae leave the coral, which turns white, hence the term “bleaching.” Bleached corals are not dead, but they are more vulnerable and more likely to die.

Most of the coral at Moorea belong to the genus Pocillopora. During the event, the researchers saw that about 72 percent of the coral colonies from this genus bleached, and up to 42 percent died afterward.

At first, it seemed that the largest colonies were more likely to bleach, but when the scientists examined tissue samples from the coral, they found that colonies belonging to a certain genetic lineage, not coral size, was most important in determining the fate of the corals.

“Because Pocillopora species look so similar, they cannot be reliably identified in the field, which, in the past, has forced researchers to study them as a single group,” said Erika Johnston, a postdoctoral researcher in the Department of Biological Science and a co-author of the paper. “Molecular genetics allows us to reconstruct their evolutionary ancestry and are an essential step to species identification in this case.”

About 86 percent of the Pocillopora corals that died belonged to a group that shares a set of DNA variations, which is known as a haplotype and reflects their common evolutionary ancestry.

“The good news is that not all of the corals died from bleaching, and many species survived,” Burgess said. “The bad news is that the species that died is, as far as we are aware at the moment, endemic to that specific region. So on the one hand, we’re worried about losing an endemic species, but on the other hand, our results show how co-occurring cryptic species can contribute to coral resilience.”

It’s an ecological analogy to having a diverse financial portfolio, where a variety of investments decreases the likelihood of a complete loss.

“Having multiple species that perform a similar function for the reef ecosystem but differ in how they respond to disturbances should increase the chance that Pocillopora corals continue to perform their role in the system, even though the exact species may be shuffled around,” Burgess said.

Maintaining healthy ecological portfolios may be a better management option than attempting to restore a specific species.

“If we maintain the right type of diversity, nature in a way can pick the winners and losers,” Burgess said. “However, the worry for us scientists is that unless the leaders of governments and corporations take action to reduce CO2 emissions, ecological portfolios that can maintain coral reef resilience will be increasingly eroded under current and ongoing climate change. This is concerning because coral reef ecosystems provide economic, health, cultural and ecological goods and services that humans rely on.”

Future research will look into the composition of the algae that live inside the coral, the depth distributions of each cryptic coral species and the evolutionary relationships among the cryptic species.

###

Researchers from the Hong Kong University of Science and Technology, the Scripps Institution of Oceanography and California State University, Northridge contributed to this study.

This work was conducted as part of a National Science Foundation grant awarded to Burgess.

From EurekAlert!

3.4 11 votes
Article Rating
34 Comments
Oldest
Newest Most Voted
Inline Feedbacks
View all comments
Mike O
March 17, 2021 10:05 am

Who’d have thought? “Survival of the Fittest.” Seems like someone should write a book on it.

Mr.
Reply to  Mike O
March 17, 2021 10:41 am

They did.
I think I saw it recently in Amazon’s clearance sale for $0.99.
Apparently, Mrs Obama’s observations about the evolution of species is more authoritative.

Ron Long
Reply to  Mike O
March 17, 2021 12:00 pm

Mike O, the “researchers” from Florida State University even admit to this survival, when then say “…genetically diverse marine invertebrates vary in their response to ocean warming”, and then again “…understand which species best coped with thermal stress.”

Zig Zag Wanderer
Reply to  Mike O
March 17, 2021 9:46 pm

Well, to my mind:

will help us understand new ways for how coral reefs maintain resilience in the face of disturbance

Says everything you need to know. Firstly it’s a tortuous sentence not worthy of seeing daylight, but more importantly, they are merely figuring out what has always happened, and always will, as long as life exists. Just as Darwin opined, as you point out.

So, reef dying scare over, then? Come to the Barrier Reef anyway, and bring those juicy tourist dollars! That’s assuming no state premier has had a brain fart and decided to close a border or lock people up in their own homes in a knee-jerk reaction to something they can’t understand.

Doonman
March 17, 2021 10:33 am

99.98% of all species that ever lived on earth are extinct. Scientists should be hysterical, but instead, they are only worried.

Herbert
Reply to  Doonman
March 17, 2021 2:29 pm

Was it the late George Carlin who said “way more than 90% of all the species that have existed on earth are extinct”.
“ I didn’t kill them. Did you?”
( Perhaps he didn’t exactly say the last part).

Rory Forbes
Reply to  Herbert
March 17, 2021 5:30 pm

But he did sat that last part … and with good reason 🙂



fretslider
March 17, 2021 10:35 am

“Maintaining healthy ecological portfolios “

Indeed

Mr.
March 17, 2021 10:48 am

Want to know what really causes bleaching?
Having a nuclear bomb exploded on top of you.
Ask the Bikini Atoll coral reefs how they coped.
Anyway, all’s well that ends well.
After being totally obliterated in the 1950s by an “extreme bleaching” event, the BI corals have regrown all by themselves back to their former glory.
The lesson for coral researchers from this would be –
“ffs just leave the corals alone”

Rory Forbes
Reply to  Mr.
March 17, 2021 5:32 pm

Wouldn’t it be a great irony if it was discovered that the corals were responding to over zealous researchers tromping all over them like locusts?

Earthling2
Reply to  Rory Forbes
March 18, 2021 9:57 am

With their sunscreen SPF 15 and all.

Wayne Townsend
March 17, 2021 10:56 am

The coral species are diverse and thus resilliant in the long-term. Who would have thought it. Biologists, perhaps? Nah.

Eric Vieira
Reply to  Wayne Townsend
March 18, 2021 6:12 am

If you’re a biologist and are worried, you get funded. If you think everything’s OK, you don’t…
in the case of Peter Ridd, you even lose your job…
That’s exactly what most “climate change scientists” do to “maintain resilience in the face of disturbance” by going with the flow.

Steve Keohane
March 17, 2021 11:09 am

“If we maintain the right type of diversity, nature in a way can pick the winners and losers,” Nature provides the diversity, and will pick the winners and losers.

Zig Zag Wanderer
Reply to  Steve Keohane
March 17, 2021 9:50 pm

Saying “nature does…” x, y or z is as wrong as saying “science tells us…” a, b or c.

Funnily enough, Climate Scientology seems full of both types of statements.

Paul of Alexandria
Reply to  Zig Zag Wanderer
March 19, 2021 4:06 pm

Gaia worship.

BCBill
Reply to  Steve Keohane
March 17, 2021 11:33 pm

Or you might say ” Everything is everywhere but the environment selects”, if you were the type of person who doesn’t mind repeating things that real scientists observed decades ago. And these authors seem to specialise in restating the obvious. Captain Obvious awards to all.

Last edited 7 months ago by BCBill
commieBob
March 17, 2021 11:23 am

… us scientists …

I was once in a large meeting where someone got up to blather and began with “We scientists …”. My reaction was, “Och aye, wee scientists indeed.”, which I did not say out loud. 🙂

Rory Forbes
Reply to  commieBob
March 17, 2021 5:34 pm

Now that’s a keeper. Who said that anecdotal evidence wasn’t valuable?

March 17, 2021 11:50 am

All my coral knowledge comes from TV (and this site), my latest understanding is that one single bit of coral replicates and populates as far as food and competition allows. Where it meets another “individual”, competition will curtail one or both, while a colony meeting with its own “self” will intertwine and grow best it can.
In other words, are these guys finding multiple clones budded from one ancestor, and calling it a “species”?
Good news that bleaching does not mean ‘dead’, though!

H. D. Hoese
March 17, 2021 1:21 pm

Cryptic-1: SECRET, OCCULT. Example– “However, the worry for us scientists is that unless the leaders of governments and corporations take action to reduce CO2 emissions, ecological portfolios that can maintain coral reef resilience will be increasingly eroded under current and ongoing climate change.”

lackawaxen123
Reply to  H. D. Hoese
March 17, 2021 2:17 pm

a claim unsupported by any evidence of course …

old construction worker
Reply to  H. D. Hoese
March 17, 2021 3:46 pm

Who would have though that coral would have survived how many ice ages and warm periods.

Rory Forbes
Reply to  H. D. Hoese
March 17, 2021 5:37 pm

It looks like many of these scientists are approaching near god status. What a heavy burden they must feel.

lee
Reply to  H. D. Hoese
March 18, 2021 12:10 am

The coral speak in tongues.

fretslider
March 17, 2021 2:02 pm

“If we maintain the right type of diversity, nature in a way can…”

These people remain utterly convinced that nature cannot cope without them.

Rud Istvan
March 17, 2021 2:05 pm

Did some research on Moorea this afternoon. There was also a bleaching event in 2016. That year, a different research team looked at the correlation between water temperature stress (onset about 28C there and usually El Nino related) and nitrogen ‘pollution’ caused by island development and runoff. Low stress but high nitrogen was worse for coral death after bleaching than high stress with low nitrogen. So there are plainly other factors than just coral stress genetics at work.

Streetcred
March 17, 2021 5:12 pm

Pocillopora sp. are like weeds, they pop up everywhere and die off for just as much reason.

Streetcred
March 17, 2021 5:15 pm

Associate Professor of Biological Science Scott Burgess has succeeded in fulfilling ambition of all “scientista” … he now knows “everything about nothing” !

Rory Forbes
March 17, 2021 5:25 pm

Stop me if I got this wrong, but doesn’t someone have to prove that CO2 is causing all this discord and angst among the various coral species? It seems to me these people are assuming responsibility for mitigating evolution in some way. How do we know if nature wants us to, “maintain the right type of diversity”? Who gets to choose these things and determine what caused them?

philincalifornia
Reply to  Rory Forbes
March 17, 2021 7:40 pm

Naaaah, no one has to prove that CO2 causes a plus/minus of 2 degrees C in the ENSO region of the Pacific within a 2 -4 year period. It’s already well established science. Haven’t you read Arrhenius (1896)?

Rory Forbes
Reply to  philincalifornia
March 17, 2021 8:49 pm

Gosh, I wish you had stopped me earlier, now I’ve gone and made a fool of myself, assuming science was based on a method and empirical evidence … so much new and “established science“. It had slipped my mind that Arrhenius is the revealed word.

March 17, 2021 7:50 pm

It will take more than just governments and corporations playing net emission heroism games. It has to be global and globally coordinated for adherence to a global carbon budget without the use of the word “net”. Pls see

https://wp.me/pTN8Y-6s3

lee
March 17, 2021 7:56 pm

““The bad news is that the species that died is, as far as we are aware at the moment, endemic to that specific region.” But subject to change. Please send funds.

%d bloggers like this: