nsf.gov - National Science Foundation - Related coral species differ in how they survive climate change effects

Genetic data reveal a tale of two corals

Two species of Porites corals growing side-by-side; the one at left is bleached. Credit and Larger Version

December 12, 2013

Ocean waters warming from climate change are placing coral reefs in jeopardy, but a new discovery suggests that two similar-looking coral species differ in how they survive.

One withstands warmer ocean temperatures better than the other.

"We've found that a previously unrecognized species was hiding some corals' ability to respond to climate change," says Iliana Baums, a biologist at Penn State University.

Baums led the research team that included Jennifer Boulay of Penn State, Jorge Cortes of the University of Costa Rica and Michael Hellberg of Louisiana State University.

A paper describing the discovery is published today in the journal Proceedings of the Royal Society B.

"These scientists have identified a 'cryptic,' or hidden, species in a common group of corals," says Michael Lesser, program director in the National Science Foundation's Division of Ocean Sciences, which funded the research.

"The two corals have very different responses to their environment," says Lesser, "and different interactions with other organisms on coral reefs."

Coral reefs protect shorelines from battering by hurricanes and generate millions of dollars in recreation revenue each year. They also provide habitat for an abundance of species used by humans as seafood and serve as a discovery ground for new medicines.

The researchers sampled the lobe coral Porites lobata in the Eastern Pacific Ocean.

"The environment for reef growth isn't the best in the Eastern Tropical Pacific," says Baums, "due to seasonally cold waters, water chemistry that makes it difficult for corals to lay down their skeletons [low aragonite for calcification], and recurring warm waters from the El Niño Southern Oscillation."

The scientists found an unexpected pattern: two coral species that look deceivingly similar and sometimes live together in the same location.

The samples were not all Porites lobata, as the researchers initially thought. Instead, some belonged to the species Porites evermanni.

"That surprised us," Baums says. "The two look identical, and we thought they were the same coral species, but Porites evermanni has a very different genetic makeup.

"We knew about Porites evermanni--it's not a new species--but we didn't expect to find it in the Eastern Pacific. Usually it's in the waters off the Hawaiian Islands."

Boulay wondered if the two differed in the way they live. She found that Porites evermanni was less susceptible to bleaching than Porites lobata.

Bleaching happens when the symbiotic relationship corals have with single-celled algae inside them breaks apart as water temperatures go up.

"If water temperatures continue to rise, coral species that succumb to bleaching more easily will die," Baums says. "We're going to see a shift in the relative abundance, for example, of these two Porites species."

Boulay found other important differences: Porites evermanni had many genetically identical clones, which means that the species is reproducing asexually by breaking apart, although Porites lobata did not.

The clonally-reproducing Porites evermanni also, on average, housed many more tiny mussels that lived in its skeletons. The mussels poked through the surface of the corals and formed keyhole-shaped openings.

The researchers then wanted to determine the connection between Porites evermanni's ability to clonally reproduce and its interactions with mussels and with other members of the reef community.

Jorge Cortes remembered that several years ago a scientist had reported finding that some corals are a target of biting triggerfish.

"That was the missing piece," Baums says. "We realized that triggerfish were eating the mussels inside the coral skeletons. To get at the mussels, the fish have to bite the coral.

"They then spit out the fragments, and those fragments land on the ocean floor and grow into new coral colonies.

"No one had realized how important fish might be in helping corals reproduce. Now there's evidence that triggerfish attacks on Porites evermanni result in asexual reproduction--the coral fragments cloning themselves."

The other coral species, Porites lobata, has fewer mussels and reproduces sexually through its larvae.

It takes two to tango, Baums says, so usually you need a partner. "But in areas of the Eastern Pacific Ocean that are so harsh that only a few individuals can survive, it might be easier for the coral to clone itself."

As for the difference in bleaching, there are two possible explanations, the scientists believe.

One is that the symbiotic algae that live in the coral species are different, and one can withstand hotter temperatures. "Just like in your garden: the tomatoes like the heat more than the cauliflower does," says Baums.

Another possibility is that the difference is not in the symbiotic algae, but in the corals themselves.

"There's been a lot of attention given to how different symbiotic algae react to increases in water temperatures and whether, if a coral species could switch to hardier algae, it could survive in hotter waters," Baums says.

But what the researchers found suggests a different scenario. Although the two Porites corals have the same symbiotic algae species, bleaching still differs.

It may be the corals themselves instead of their symbiotic algae that contribute to bleaching.

A tale of two corals, and a tale, perhaps, of more than two factors.

-NSF-

Media Contacts Cheryl Dybas, NSF (703) 292-7734 cdybas@nsf.gov
Barbara Kennedy, PSU (814) 863-4682 science@psu.edu

Related WebsitesNSF Award: Predicting the effects of ocean warming on larval dispersal by measuring adaptive potential of corals:

 http://www.nsf.gov/awardsearch/showAward?AWD_ID=0825979&HistoricalAwards=false

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2012, its budget was $7.0 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives about 50,000 competitive requests for funding, and makes about 11,500 new funding awards. NSF also awards about $593 million in professional and service contracts yearly.

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Researchers sample lobe corals of the species Porites lobata.
Credit and Larger Version

Keyhole-shaped openings in this Porites coral are made by tiny mussels living inside.
Credit and Larger Version

Small mussels inside the coral colony have pockmocked its surface with openings.
Credit and Larger Version

Side view of mussels living inside the coral skeleton. The green/brown is living coral.
Credit and Larger Version

Triggerfish bite adult lobe corals to get at mussels; coral fragments grow into new colonies.
Credit and Larger Version

 

The National Science Foundation (NSF)

Guillermo Gonzalo Sánchez Achutegui

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nsf.gov - National Science Foundation - Life in the Fast Lane: Racing to Identify Species as Biodiversity Shrinks

A conversation about conserving and naming species.-
 

Without significant changes, more than 50 percent of the world's marine species may be perched on the brink of extinction by 2100, according to UNESCO.

Credit: Dan Norton (for commercial use, contact photobank@coral.org)

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 Daphne Fautin searches for new organisms while conducting a marine survey.
Credit: Rita Tan of www.wildsingapore.com
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Name that Species! A conversation about conserving, finding and naming species with NSF Program Manager Daphne Fautin
Credit: National Science Foundation
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A little more than 39 years ago, on December 28, 1973, the Endangered Species Act was enacted to conserve threatened and endangered species and their ecosystems. To honor this anniversary, Daphne Fautin of the National Science Foundation answered questions about biodiversity.

As a marine biologist, Fautin has literally gone to the ends of the Earth--from the poles to the tropics--to study marine life. She is currently a program manager at the National Science Foundation, a professor of ecology and evolutionary biology at the University of Kansas, and a commissioner with the International Commission on Zoological Nomenclature, which produces rules on giving scientific names to animals.

What is biodiversity?

Biodiversity--short for "biological diversity"--is the variety and abundance of plants, animals and other living things on Earth and in particular locations. Biodiversity is absolutely essential to ecosystem health. And human survival depends on the health of our planet's ecosystem.

Rain forests and coral reefs are known for their biodiversity. Why is so much biodiversity concentrated in these types of ecosystems?

More than 25 percent of the world's fish species and between nine and 12 percent of all of the world's fisheries are associated with coral reefs. More than half of the world's plant and animal species live in rainforests.

We don't know for sure why rain forests and coral reefs harbor so much biodiversity. One idea is that these ecosystems occur in tropical climates, and so they are quite climatically consistent year-round.

According to this idea, tropical organisms diverged because they don't have to deal with the climatic extremes that organisms at higher latitudes (and altitudes) do. A rabbit, for example, that lives in a non-tropical place must be able to eat certain plants in the summer and certain other plants in the winter. Therefore, it must remain a generalist to survive.

By contrast, a rabbit that lives in the tropics may specialize in eating certain plants that are available year-round; at the same time, other species of rabbits (or other organisms) may evolve that specialize in eating other plants. Such specialization promotes diversity.

But some evidence does refute this idea--such as the fact that not all groups of plants and animals demonstrate more diversity in the tropics than at higher latitudes. So, many other ideas have also been proposed to explain the extraordinary biodiversity of the tropics.

Insects account for a large proportion of the biodiversity on Earth. Why?

Many statistics bear out the biodiversity of insects. For example, more than 850,000 insect species have been named. And the total estimated weight of just ants in the Amazon is four times the estimated weight of all land vertebrates in the Amazon--including all mammals, birds, reptiles and amphibians!

We don't really know why insects account for so much of the Earth's biodiversity. That is one of the questions that is being studied by entomologists--the people who research insects.

One idea is that insects began to diversify when flowering plants evolved on Earth, and so insects evolved along with flowering plants because they are so important in the pollination of plants.

Insects tend to be small and specialized: So there may be a certain insect that sucks out the cell sap from the stems of a particular plant; other insects that eat that plant's leaves; other insects that feed on that plant's nectar; and other insects that feed on that plant's pollen and pollinate the plant in the process. So as flowers evolved, many insects evolved as well.

This idea about the evolutionary connections between flowering plants and insects is consistent with what we see in the oceans: Relatively few species of flowering plants live in the oceans, and relatively few species of insects live in the oceans.

(By the way, NSF recently issued a press release that identified some interesting reasons why humans need insects--even pesky ones.)

How many species have been described and named by scientists, so far?

The Encyclopedia of Life estimates that there are 1.9 million known eukaryotic organisms. (Eukaryotic organisms are those that are made of one or more cells with a nucleus; bacteria and viruses are not eukaryotic organisms.)

How many species exist on Earth?

Estimates range from 2 million species to 10 million species.

A recent estimate of 8.7 million species received a lot of press, in part, I suspect, because of its supposed accuracy and because it corresponds quite well to the often-bandied figure that 80 percent of the Earth's biodiversity has yet to be discovered/named. The Encyclopedia of Life states that "at least four times" the number of known species exist on Earth. Based on its own figures, this translates to around 8 million species.

A paper estimating the number of marine species (which I contributed to) was recently published. According to this paper, 226,000 species that live in the ocean have been named and described by scientists, and 72,000 additional species are in collections waiting to be named and described.

But who knows what hasn't been collected yet? And of course, as I previously mentioned, oceans have few insects, but insects account for the bulk of biodiversity.

How can scientists estimate the total number of species on Earth when it is obviously impossible to count what has not yet been counted. In other words, how can we know what we don't know?

People have used various creative methods to estimate the total number of organisms on Earth. For example, there was a very large estimate made years ago by a scientist who went to the jungles of Panama and used insecticide to spray a tree in the jungle. Then, lots of insects died and fell from the tree to the ground. And the scientist and his colleagues identified and counted as many of these fallen insects as they could, and the rest were counted as unknown. Then, the scientist extrapolated from the proportion of species in that one tree that were known vs. unknown to produce a global estimate of known vs. unknown species.

It was good first try. But a lot of people point to the fact that in many parts of the world, the proportion of known species to unkown species is higher than it is in Panama. So this fact would suggest that the estimate may be excessive.

In 2011, an NSF-funded researcher provided the first empirical evidence of what had been long suspected: That biodiversity promotes water quality. What are some of the other reasons why need biodiversity?

We need biodiversity to eat, we need to preserve species that we use as food, including fish from the sea. We also need to preserve those species that serve as food for the fish we eat, so that our food supply persists. And we also need to preserve all the species that create the habitat that enables all of these needed species to live, spawn, and raise their young.

So, there are all of these connections in the great "web of life" that we don't even know yet. And these connections support all of the species on Earth, including species that provide us with food and clothing.

Also, 50 percent of the oxygen we breathe is produced by microscopic plants that live in the ocean and the other 50 percent is produced by plants that live on land.

(If you want to learn more about the ways in which the various species of plants help humans survive, watch this dynamic, upbeat video produced by NSF.)

The planet's ecosystem is sometimes compared to an airplane. You can lose one rivet from an airplane, and the airplane will probably fly. You can lose two rivets for an airplane and the airplane will still probably fly. But eventually, if you lose too many rivets (how many?), the plane will crash.

The same principle applies to ecology: You can lose some species without major harm. But no one knows how many species can be lost before the planet's ecosystem will crash.

What does it mean to discover a new species?

A new species is one that hasn't yet been formally described and named according to scientific procedures--not one that is newly evolved.

People on the street or people in the jungle may have a name for it. But if we haven't followed the internationally recognized rules of nomenclature for describing and naming a species, it doesn't exist for certain scientific purposes.

When we have discovered a new species, it means we have finally found and gone through the procedures of formally describing it (distinguishing it from other species) and giving it a name following the rules of nomenclature.

How many new species are named each year?

Between 15,000 and 20,000 new species are named each year.

A species may be discovered and collected before it is described and named. But it isn't recognized as a new, distinct species until it is described and named.

How many species go extinct each year?

We don't know. The World Wildlife Fund's Web site says that experts have calculated that between .01 percent and .10 percent of all species on Earth go extinct each year.

But because we don't know how many species there are, we don't know how many species those percentages actually represent. And so, if the low estimate of the number of species on Earth is true--if there are around 2 million species on our planet--then between 200 and 2,000 extinctions occur each year.

But if, in fact, there really are 10 million species on Earth, then between 10,000 and 100,000 extinctions occur each year.

What would you say to naysayers who argue that newly discovered species offset species losses, and so there really is no extinction crisis?

"New" species are not newly evolved. They evolved a long time ago. They are simply being newly discovered by science. They may be very well known to the people living in the areas where they live. So they aren't new in that sense; they are only new to those of us who name them.

What does the process of naming a species involve?

It can be long, protracted and difficult process that can take many years. First, you want to be sure that the animal or plant hasn't been named before.

This can be difficult for a variety of reasons. For one thing, many descriptions that were prepared in the early days were very vague. And usually, only small groups of experts have the specialized expertise to know what has and hasn't been described before.

And in order to name a species, you also have to describe it. To do this, you have to know what kinds of features are used to identify species, and figure out what distinguishes the "new" species from known species. This is important, because at least according to the rules of zoological nomenclature, when you publish a description of a new species, you have to write out what makes it different from everything that is already known--including organisms that are not closely related to it, but that look like it anyway.

For example, suppose you have an organism that has a red spot; then you have to distinguish your "new" species from everything that is red-spotted, even if those other red-spotted species are not closely related to your species. That way, when somebody comes across your species, they can say, "AHA! This is another one of those red-spotted organisms that is covered by that new name; it's not another thing with red spots."

Other rules in the codes of nomenclature require you to name species in Latin or make them sound like Latin. You also have make sure a specimen of your species is deposited in a natural history collection (typically in a museum or herbarium). If the "new" species is an animal, you may also have to register the name in ZooBank.

And then you have to publish your description of the species in a scientific journal, so that other scientists can look at it and agree that it is correct.

It is interesting to note that names that are accepted are frequently later "sunk" for various reasons. For example, when the exhaustive homework that is required for describing and naming a "new" species is not conducted in a comprensive and thorough way, it may ultimately turn out that the "new" species has already been described and named.

Alternatively, a name for a "new" species may be sunk because the difference that was thought to distinguish it from others does not hold up. For example, I have a colleague who described several coral reef fish as "new"--only to ultimately discover that the "new" species was a member of a species for which only one sex had previously identified. So the "new" species was really just a female (or male) of a known species!

Do you have to be a professional taxonomist to identify and name new species?

About half of the species that are named each year are named by people who aren't employed as taxonomists--whose job isn't in a museum or university. In fact, some of the people with the most expertise and time to do this are not professionals in the field.

For example, I knew a dentist who is one of the world's foremost authorities on tiger beetles. He had earned a master's degree in entomology. And then he realized that if he had gone into academic entomology, he would be spending his time teaching, writing grant proposals and doing administrative work--but he wanted to catch tiger beetles.

And so he went into dentistry so that he could make enough money to take time off each year to catch tiger beetles. He probably thereby ended up being able to spend more time chasing tiger beetles as a dentist than he would have if he had become a professional entomologist.

A new species of frog was recently identified by an NSF-funded researcher right smack in New York City. Is that common for new species to be discovered in such populated places?

I think that it is quite common for new species to be found in populated areas.

In the summer of 2012, an NSF-funded researcher named a new coral reef crustacean after Bob Marley, the singer. Is that unusual for species to be named after celebrities?

It may be less common than it used to be.

Many years ago, it would be common for a patron to fund the travels of a scientist to exotic places, and then species that were found during those travels would be named for the patron.

Tell me about one of the big problems that is reducing biodiversity in the oceans?

We have depleted the oceans of many of the big fish that we eat.

Part of the reason we are able to overfish is due to technology. We have fish-finders: various types of tracking devices, including sonar equipment, and airplanes that are used to help find schools of fish. And we now know enough about marine biology to predict where fish and crustaceans will be under particular conditions. Fishing is no longer about a fisherman just saying, I'll drop a line here or there." Fishing has become very scientific and methodical.

When we trawl, we drag nets along the ocean floor. And whatever else gets swept by these nets in addition to the target fish is called "bycatch." This bycatch gets thrown back into the ocean because we are not licensed to take it or because it's not profitable to take.

But how many organisms can manage to survive after being caught in a big net, pulled up and then thrown back into the ocean? What's more, trawling destroys habitat; after the ocean floor has been trawled, it may no longer be a suitable home for what is thrown back.

The analogous situation on land would be if we flew an airplane that dragged a big net across the ground to catch grazing cattle. And we would draw up the net periodically--and keep the cattle, but toss back the dogs, trees and everything else that we happened to net in addition to the cattle. That is similar to what we do to the oceans.

Many people assume that it is necessarily better to consume farmed fish and shrimp than wild caught fish and shrimp. But many fish and shrimp farming practices are also harmful to the environment. Just because it is farmed doesn't mean that it is environmentally neutral or preferred over wild caught.

Can you cite any "good news" stories in biodiversity?

I read the other day that we have lost 97 percent of wild tigers in just over a century. Only about 3,200 tigers currently remain in the wild. We can infer that the populations of many smaller species are plummeting just like populations of many large species are plummeting.

But I am happy to say that a few species have come off the endangered species list, like the wolf and the bald eagle, because plans for their recovery were enacted.

Also, there are "good news" stories in the history of whales. Many of them were hunted to the brink of extinction, and then they were listed as endangered. It therefore became legally, socially and economically difficult to harvest whales, and so populations of many whale species have fortunately recovered.

These kinds of successes show that if we stop harvesting species, and if their habitat is conserved, life is resilient and endangered species may recover.

Additional Resources

To learn more about biodiversity and help promote conservation:

• Read about the Endangered Species Act on the websites of the U.S. Fish & Wildlife Service and the National Oceanic and Atmospheric Administration.
• Join citizen science groups that work to identify and track species of birds, butterflies, ladybugs, plants and other creatures, advance our understanding of nature, and increase habitat for wildlife.
• Restrict your seafood purchases in restaurants and stores to ocean-friendly products. Resources provided by the Monterey Bay Aquarium's Seafood Watch Program may help you do so.

--	Lily Whiteman, National Science Foundation (703) 292-8310 lwhitema@nsf.gov

Investigators
Daphne Fautin 

Guillermo Gonzalo Sánchez Achutegui

ayabaca@gmail.com

ayabaca@hotmail.com

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nsf.gov - News - Coral Reef 911: Corals Attacked by Seaweed Use Chemical Signals to Summon Help

Goby fish on a coral reef in Fiji; green algae are moving in on the coral, but gobies rescue.
Credit: Danielle Dixson
Credit and Larger Version

 Scene of the crime: Fiji and its coral reefs in a vast ocean.
Credit: Wikimedia Commons
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A goby on-the-job: it's feeding on algae that would otherwise cover the coral.
Credit: Danielle Dixson
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Goby fish in the genus Gobiodon: the fish are common coral reef residents in Fiji.
Credit: Wikimedia Commons
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Close-up of Acropora coral: it "calls 911" when it chemically senses certain algae.
Credit: Wikimedia Commons
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The research results are described in the Nov. 9, 2012 issue of the journal Science.
Credit: AAAS Copyright 2012
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Corals under attack by toxic seaweed do what anyone might when threatened--they call for help.

Results reported this week in the journal Science show that threatened corals send signals to fish "bodyguards" that quickly respond to trim back noxious algae, which can kill the coral if not promptly removed.

Scientists at the Georgia Institute of Technology found evidence that these "mutualistic" fish respond to chemical signals from the coral in a matter of minutes, like a 911 emergency call.

The inch-long fish--known as gobies--spend their entire lives in the crevices of specific corals, receiving protection from their own predators while removing threats to the corals.

"These findings illustrate the complexity of coral reef systems," said David Garrison, program director in the National Science Foundation's Division of Ocean Sciences, which funded the research. "This newly discovered relationship may be a key factor in the resilience of some coral species."

The symbiotic relationship between fish and the coral on which they live is the first known example of one species chemically signaling a consumer species to remove competitors.

It is similar to the symbiotic relationship between Acacia trees and mutualist ants, in which the ants receive food and shelter while protecting the trees from both competitors and consumers.

"This species of coral is recruiting inch-long bodyguards," said Mark Hay, a biologist at Georgia Tech and co-author of the paper. "There is a careful and nuanced dance of odors that makes all this happen.

"The fish have evolved to cue on the odor released into the water by the coral, and they very quickly take care of the problem."

The research was part of a long-term study of chemical signaling on Fiji Island coral reefs. It was aimed at understanding these threatened ecosystems and discovering chemicals that may be useful as pharmaceuticals.

The importance of large herbivorous fish to maintaining the health of coral reefs has been known for some time. They control the growth of seaweeds that damage coral.

But Georgia Tech scientist Danielle Dixson, also a co-author of the paper, suspected that the role of the gobies might be more complicated.

To study that relationship, she and Hay set up a series of experiments to observe how the fish would respond when the coral that shelters them was threatened.

They studied Acropora nasuta, a species in a genus of coral important to reef ecosystems because it grows rapidly and provides much of the structure for reefs.

To threaten the coral, they moved filaments of Chlorodesmis fastigiata, a species of seaweed that is particularly chemically toxic to corals, into contact with the coral.

Within a few minutes of the seaweed touching the coral, two species of gobies--Gobidon histrio and Paragobidon enchinocephalus--moved toward the site of contact and began neatly trimming away the offending seaweed.

"These little fish would come out and mow the seaweed off so it didn't touch the coral," said Hay.

"This takes place very rapidly, which means it must be very important to both the coral and the fish. The coral releases a chemical and the fish respond right away."

In corals occupied by the gobies, the amount of offending seaweed declined 30 percent over a three-day period, and the amount of damage to the coral declined by 70 to 80 percent.

Control corals that had no gobies living with them had no change in the amount of toxic seaweed and were badly damaged by it.

To determine what was attracting the fish, Dixson and Hay collected samples of water from several locations: near the seaweed itself where the seaweed was contacting coral and from coral that had been in contact with the seaweed 20 minutes after the seaweed was removed.

They released the samples near other corals that hosted gobies, which were attracted to the samples taken from the seaweed-coral contact area and the damaged coral, but not the seaweed by itself.

"We demonstrated that the coral is emitting some signal or cue that attracts the fish to remove the encroaching seaweed," Hay said. "The fish are not responding to the seaweed itself."

Similar waters collected from a different species of coral placed in contact with the seaweed did not attract the fish, suggesting they were only interested in removing seaweed from their host coral.

Finally, the researchers obtained the chemical extract of the toxic seaweed and placed it onto nylon filaments designed to simulate the mechanical effects of seaweed.

They also created simulated seaweed samples without the toxic extract.

When placed in contact with the coral, the fish were attracted to areas in which the chemical-containing mimic contacted the coral, but not to the area contacting the mimic without the chemical.

By studying the contents of the fish digestive systems, the researchers learned that one species--Gobion histrio-- actually eats the noxious seaweed, while the other fish apparently bites it off without eating it.

In the former, consuming the toxic seaweed makes the fish less attractive to predators.

The two species of fish also eat mucus from the coral, as well as algae from the coral base and zooplankton from the water column. By defending the corals, the gobies are defending the home in which they shelter and feed.

"The fish are getting protection in a safe place to live and food from the coral," Hay said. "The coral gets a bodyguard in exchange for a small amount of food.

"It's kind of like paying taxes in exchange for police protection."

As a next step, Hay and Dixson plan to determine whether other species of corals and fish have similar symbiotic relationships.

The research was also supported by the National Institutes of Health and the Teasley Endowment at Georgia Tech.

-NSF-

Media Contacts Cheryl Dybas, NSF (703) 292-7734 cdybas@nsf.gov
John Toon, Georgia Tech (404) 894-6986 john.toon@innovate.gatech.edu

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2012, its budget is $7.0 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives over 50,000 competitive requests for funding, and makes about 11,000 new funding awards. NSF also awards nearly $420 million in professional and service contracts yearly.

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 The National Science Foundation (NSF)

Guillermo Gonzalo Sánchez Achutegui

ayabaca@gmail.com

ayabaca@hotmail.com

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