The National Science Foundation (NSF) : Caribbean bat species need 8 million years to recover from recent extinction waves .- Las especies de murciélagos del Caribe necesitan 8 millones de años para recuperarse de las recientes olas de extinción.....

https://www.nsf.gov/discoveries/disc_summ.jsp?cntn_id=190744&WT.mc_id=USNSF_1

Bats include the fishing bat, vampire bats and many fig-eating species

 

Each evening, thousands of bats rush out of caves in the Caribbean, here seen in Puerto Rico. Credit and Larger Version

January 9, 2017

Find related stories on NSF's Environmental Research and Education and Dimensions of Biodiversity programs.

How long does it take a community of mammals to recover after a wave of species loss? Bats in the Caribbean Islands may hold new answers, biologists report in a paper published this week in the journal Nature Ecology & Evolution.

 

Caribbean Island bats form an ecologically diverse group that includes the fishing bat, vampire bats and many species of fig-eating bats. Because one-third of the group has disappeared over the past 20,000 years in the Greater Antilles -- islands in the Caribbean Sea that include Cuba and Jamaica -- the bats are ideal for studying the effects of extinctions, scientists say.

 

Using computer simulations, the researchers estimated how long it would take natural processes to restore the number of bat species that lived in the Greater Antilles 20,000 years ago.

 

"We discovered that it would take at least eight million years to regain the bat species lost," says Liliana Dávalos of Stony Brook University, co-author of the new paper. Funded through the National Science Foundation's (NSF) Dimensions of Biodiversity Program, Dávalos and Luis Valente of the Berlin Natural History Museum in Germany led a research team that compiled data on New World leaf-nosed bats and their relatives.

 

"The incredibly long time required to restore biodiversity shows the staggering consequences of extinctions, many caused by humans, on the long-term ecology of islands," Dávalos says.

 

Islands are natural laboratories of evolution and home to unique animals and plants, yet many have lost native species. While there is a debate as to what caused the Caribbean bat extinctions, the largest wave of species loss came after humans arrived, when more than half the islands' mammal species went extinct. Bats are now the most diverse group of surviving Caribbean terrestrial mammals.

 

According to Dávalos, the number of species on an island results from a balance of colonization, the formation of new species, and losses from extinction. The researchers studied these processes based on the evolutionary histories of bat species both alive and extinct.

 

They found that bat species in the Greater Antilles remained relatively stable over millions of years, but that recent extinctions -- most likely caused by habitat loss -- have disrupted this natural balance.

"Bats have been here a long time," Dávalos says. "We need to find ways of ensuring they will be long into the future."

 

Knowing how long it would take the bats to return will help researchers understand how animals adapt to changing environments, and how other animals might avoid similar fates.

 

"Human-caused changes to Earth's ecosystems are accelerating," says Leslie Rissler, program director in NSF's Division of Environmental Biology. "This study offers important information on how those changes will affect the loss and recovery of species in the future."

 

In addition to NSF, the Alexander von Humboldt Foundation; the Brandenburg Ministry of Science, Research and Culture; and the Netherlands Organisation for Scientific Research supported the research.

--	Cheryl Dybas, NSF (703) 292-7734 cdybas@nsf.gov
--	Greg Filiano, Stony Brook University (631) 444-9343 gregory.filiano@stonybrookmedicine.edu

Investigators Stephen Rossiter
Liliana Dávalos Alvarez
Related Institutions/Organizations SUNY at Stony Brook
Related Awards #1442142 Dimensions: Collaborative Research: Discovering genomic and developmental mechanisms that underlie sensory innovations critical to adaptive diversification
Total Grants $584,728

Caves are critical habitats for Greater Antilles bats. Bats rebound slowly from loss of habitat.
Credit and Larger Version

The Cuban fruit-eating bat, a species in the Greater Antilles, where it eats fruit, visits flowers.
Credit and Larger Version

The Antillean ghost-faced bat hunts moths and other insect prey along forest edges.
Credit and Larger Version

The greater bulldog bat, or fishing bat, listens for echoes over the water to detect its fish prey.
Credit and Larger Version

Biologist Liliana Dávalos conducting research in the lab with students.
Credit and Larger Versión

The National Science Foundation (NSF)
Guillermo Gonzalo Sánchez Achutegui
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NASA: Caribbean Sea Viewed From the International Space Station

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Caribbean Sea Viewed From the International Space Station

From the Earth-orbiting International Space Station, flying some 225 nautical miles above the Caribbean Sea in the early morning hours of July 15, NASA astronaut Reid Wiseman photographed this north-looking panorama that includes parts of Cuba, the Bahamas and Florida, and even runs into several other areas in the southeastern U.S. The long stretch of lights to the left of center frame gives the shape of Miami.

Image Credit: NASA

NASA
Guillermo Gonzalo Sánchez Achutegui
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nsf.gov - National Science Foundation - Sick Sea Fans: Undersea "Doctors" to the Rescue

Scientists discover genes involved in immunity of sea fans to coral diseases.-

In sea fans, scientists discover new immunity genes. See photo gallery for sea fan 'Message in a Bottle.'
Credit: NSF
Credit and Larger Version

A sea fan fights back against disease; its response is marked by dark purple inflammation. Credit: E. Weil

Download the high-resolution JPG version of the image. (804 KB)

Scientist Drew Harvell examines sea fans in Puerto Rico for signs of recovery. Credit: E. Weil

Download the high-resolution JPG version of the image. (668 KB)

Beautiful and healthy now, the purple sea fan may fall ill from a host of infectious diseases. Credit: Wikimedia Commons

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Close-up of formerly sick sea fan that's recovering nicely from ocean diseases. Credit: D. Harvell

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Marine ecologist Ernesto Weil looks at a sick sea fan; he's studying sea fan immune systems. Credit: D. Harvell

Download the high-resolution JPG version of the image. (506 KB)

The following is part five in a series on the NSF-NIH Ecology and Evolution of Infectious Diseases (EEID) Program. For part one, see Cool Cat in a Hot Zone. For part two:

Snails in the Waters, Disease in the Villages.

For part three: Underwater Whodunit: What's Killing Florida's Elkhorn Coral?

For part four: "Defective" Virus Leads to Epidemic of Dengue Fever.

Like all of us, corals get sick. They respond to pathogens (disease-causing microbes) and recover or die. But unlike us, they can't call a doctor for treatment.

Instead, help has arrived in the form of scientists who study the causes of the corals' disease, and the immune factors that might be important in their response and resistance.

With support from the National Science Foundation (NSF), scientists Drew Harvell and Colleen Burge of Cornell University and their colleagues have developed a catalog of genes that, the researchers say, will allow us to better understand the immune systems of corals called sea fans.

The marine ecologists have trained their undersea eyes on a particular sea fan species, Gorgonia ventalina, or the purple sea fan, found in the western Atlantic Ocean and the Caribbean Sea.

The team has monitored sea fan health in the Florida Keys, Mexican Yucatan and Puerto Rico for the past 15 years. The most recent research, in collaboration with Ernesto Weil of the University of Puerto Rico, is underway on reefs at La Parguera, Puerto Rico.

Gorgonia ventalina is a fan-shaped coral with several main branches and a latticework of smaller branches. Its skeleton is composed of calcite and gorgonian, a collagen-like compound. Purple sea fans often have smaller, accessory fans growing sideways out of their main fans.

These large sea fans fare best near shore in shallow waters with strong waves and on deeper outer reefs with strong currents, down to a depth of about 50 feet. Small polyps on the graceful fans catch plankton drifting by on fast-flowing currents.

Turning (more) purple

Life as a purple sea fan isn't always easy. The coral may be attacked by the fungus Aspergillus sydowii, which causes the disease aspergillosis.

It results in damaged patches on the fan, extreme purpling of tissues and sometimes death. Several outbreaks of aspergillosis have occurred in the Caribbean; corals in stressful conditions such as warming waters may be especially susceptible.

"Diseases and climate change are very tightly linked," says Mike Lesser, program director in NSF's Division of Ocean Sciences, which funds the research along with the joint NSF-National Institutes of Health Evolution and Ecology of Infectious Diseases (EEID) Program.

"The role of climate change in diseases is important," Lesser says, "for understanding the spread of infectious diseases in every corner of the globe, including the oceans."

Adds Sam Scheiner, NSF EEID program director, "Human-induced climate change is having profound effects on many parts of the world. As this research shows, coral reefs are being decimated by the combination of climate change and infectious diseases."

Undersea "doctors" come to sea fans' aid

Harvell agrees.

In a paper published earlier this year in The Annual Review of Marine Science, Harvell, Burge and other scientists reviewed climate change influences on marine infectious diseases.

Now the scientists are using the purple sea fan as a model for studying ocean diseases. "We're looking at microbial infection, pathways of defense and the health of this sea fan in the face of warming waters and climate change," says Harvell.

"All animals on Earth--from humans to fish to corals--are susceptible to infection by pathogens that cause illness," she says. "What we hope to answer is: How widespread are these infections? Why do they happen? And, what can we do about them?"

Coral reefs are declining worldwide. Even very old coral colonies in remote locations are dying. "Disease-related deaths are caused in part by pathogens alone and in part by interactions between pathogens and climate change," says Burge.

Many of these pathogens are unidentified, leaving sea fans and their coral relatives at high risk.

But the mystery is slowly being solved.

The scientists have discovered two pathogens in purple sea fans. The microbes are being cultured and used to examine how sea fans' immune systems work.

Past is prologue?

A look back a decade or more may provide clues to the present--and the future--for sea fans.

From 1996 through 2004, thousands of sea fans in the Caribbean died of aspergillosis. Many survived, however, and appear resistant to further attack.

But they're far from home free.

Purple sea fans are now being infected by a new pathogen, called Aplanochytrium. Burge was the first to isolate and culture the microbe from a sick sea fan.

Aplanochytrium is a member of an order of lethal microbes known as Labyrinthulomycetes. It grows faster at warmer temperatures, leaving sea fans in "hot water."

Corals don't have "immune memory," such as the T cells and antibodies found in humans. Instead they have an ancient defense system called the innate immune system.

Studying sea fans' immunity through their genes is an important step in protecting them, says Burge.

"We used molecular biology and bioinformatics--a combination of biology, computer science and information technology--to make a set of the genes' messages, called transcripts," she says. "Then we characterized these messages, which are known collectively as a transcriptome."

The results, reported this month in a paper in the journal Frontiers in Physiology, are the first to show which genes are activated in response to pathogens in sea fans. Co-authors of the paper are Burge, Harvell and Morgan Mouchka of Cornell, and Steven Roberts of the University of Washington.

Message in a (genetic) bottle

The purple sea fan may hold messages for the oceans, and for us, but the messages come in a genetic bottle.

The scientists studied what's called messenger RNA, which transfers genetic messages, in sea fans exposed to Aplanochytrium, comparing it with that of unexposed sea fans.

They found that the sea fans' genes hold clues to questions such as how the fans recognize and kill pathogens, and how they repair injured tissues.

The scientists are increasing the sea fan genetic "catalog" by adding genes expressed, or turned on, in response to record-breaking Caribbean Sea temperatures in 2010.

The researchers, working in Puerto Rico with Weil and Laura Mydlarz of the University of Texas at Arlington, assessed the effect of the 2010 Caribbean coral bleaching event, as it's known, on sea fans' genes and immune function.

The study compared immune system genes in a heat-sensitive coral species, Orbicella annularis, the boulder star coral, with that of Gorgonia ventalina.

The purple sea fan was thought to be resilient to the stresses of warming waters. But Gorgonia ventalina, the scientists found, is also susceptible to the double whammy of disease and warming.

--	Cheryl Dybas, NSF (703) 292-7734 cdybas@nsf.gov

Related WebsitesNSF Special Report: The Ecology and Evolution of Infectious Diseases:

 http://www.nsf.gov/news/special_reports/ecoinf/index.jsp
NSF Award: EEID: Evaluating the Effects of a Changing Ocean on Management and Ecology of Infectious Marine Disease:

 http://www.nsf.gov/awardsearch/showAward?AWD_ID=1215977
NSF Award: Effect of the 2010 Caribbean Coral Bleaching Event:

 http://www.nsf.gov/awardsearch/showAward?AWD_ID=1105201&HistoricalAwards=false
NSF News: Controlling the Spread of Diseases Among Humans, Other Animals and the Environment:

http://www.nsf.gov/news/news_summ.jsp?cntn_id=125496

Guillermo Gonzalo Sánchez Achutegui

ayabaca@gmail.com

ayabaca@hotmail.com

ayabaca@yahoo.com

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