Mushroom Coral

Domain: Eukarya
Kingdom: Animalia
Phylum: Cnidaria
Class: Anthozoa
Order: Scleractinia
Family: Fungiidae
Genus: Fungia
Species: Fungia scruposa

Do you know what gets my attention? An old article about a species of coral that was documented eating jellyfish. But I’ll get to that later; first, I want to introduce you to Fungia scruposa, or the mushroom coral!

Found in the tropical waters of the Red Sea, Indian Ocean, and western Pacific Ocean, mushroom coral are unique for a few reasons. Unlike other hard corals, F. scruposa lives as a single individual instead of as a colony, much like the Atlantic mushroom coral of the family Mussidae. Don’t let their similar common names fool you, though. These two corals are not closely related to each other.

Juvenile mushroom coral start out as raised disks that attach to dead coral or rock. When they grow to about an inch in diameter, they detach themselves from their substrate. However, this does not mean that they’re super mobile. Instead, mushroom coral typically stay in the same area and inhabit the sediment or rubble.

But what happens if a strong wave comes through and turns them over? Fungia scruposa use their tentacles to right themselves when knocked over by waves or by another animal.

Mushroom coral get their name from their appearance. They have an irregular disk shape that is about 1 inch in diameter, sometimes a little larger. At the center of the disk is a raised mound with a deep-looking cut, which is the polyp’s mouth. The coral’s hard exoskeleton has several thin ridges that spread out from the center, making it look like the underside of some mushrooms.

Fun fact: did you know that the ridges on the undersides of mushrooms are called gills?

I’ve yet to see this coral while diving, but I absolutely cannot wait! Mushroom coral are unique for their class, because they live as solitary polyps and spend their adult lives not attached to anything. But on top of all that, they were also recorded eating whole jellyfish in the late 2000s—something that was completely unheard of!

There are some species of sea anemones—distant cousins to coral—that are known to eat jellyfish. However, these are the first hard corals that scientists have seen eating jellies. Unfortunately, the divers were only able to see the jellies disappear into the mouths of several mushroom coral, but they could never see how the mushroom coral captured the moon jellies. Still, it’s absolutely fascinating and may prove how resilient hard coral can be in a changing ocean environment.

And maybe you can be the researcher that discovers how they do it! Maybe you can discover more species of coral that will dine on jellyfish when the opportunity presents itself.

Sources and links:
Ocean The Definitive Visual Guide made by American Museum of Natural History
http://www.coralsoftheworld.org/species_factsheets/species_factsheet_summary/fungia-scruposa/
http://news.bbc.co.uk/earth/hi/earth_news/newsid_8350000/8350972.stm ⇐an article about mushroom coral eating jellies
https://link.springer.com/article/10.1007/s00338-009-0507-7 ⇐another article about them eating jellies but with more detail

NeMO-Net

Everybody likes to play games, especially video games. Whether it’s a high-resolution, top-notch game with amazing graphics or a simple game of solitaire on your computer, everybody plays games. Even my mom plays Borderlands by GearBox and 2kGames, my dad plays card games on his computer between grading his students’ assignments, and my half-blind aunt plays mahjong on her Kindle.

Everybody likes to play games, and NASA decided to take advantage of that.

One of the difficulties in studying coral reefs is the limitations we have as humans. It’s best to study them in person, but because reefs are underwater, we need tanks to breathe artificial air so we don’t drown while we collect data. We also can’t spend the whole day diving without dying.

Reefs also are pretty spread out and aren’t always close to the shore, so it takes time to travel to all of them and collect data. Funding is an issue because boats and fuel cost money, along with the standard dive equipment, air for the tanks, and the equipment for research.

We also don’t know where all the reefs are in the ocean. In fact, we have mapped out more of the surface of the moon than we have our own oceans—so, who knows where all the coral are!

Speaking of the moon, NASA decided to help coral researchers. They took the same equipment they use to look at stars and pointed them toward our oceans. We can’t use standard camera lenses to photograph reefs from above because of a special law called Snell’s law or the law of refraction.

The law of refraction—which I described in an earlier post—explains how light bends (or refracts) as it passes from one medium to another. Refraction makes taking aerial shots of coral reefs problematic because the subjects become distorted in the image. Using their fluid-correcting lenses, which are manufactured to take Snell’s law into account, NASA has deployed drones and small planes to take pictures of reefs around the world and produce 3D images of what the reefs should look like underwater.

That’s great and all, but all those coral need to be identified, which can take thousands of man hours and hundreds of people. By the time all of the pictures are processed and the coral identified, the reefs may look drastically different and all that data may no longer be relevant. So NASA decided to use the help of video gamers and citizen science to identify all the coral in their photos.

The Neural Multi-Modal Observation and Training Network (NeMO-Net) was created to help marine scientists identify and protect coral. The NeMO-Net game allows players to look at real 3D images of reefs and identify different families of coral, what’s just sand or an invertebrate on the seafloor, and other objects. Players color-code the image based on what they see, so each coral family has its own color, and then players upload their image to a database where other players and scientists can agree or correct what was submitted.

The approved images are used to train a supercomputer at the Ames Research Center to look through collected images and correctly identify what it sees, so that eventually the supercomputer can do it on its own. A supercomputer doesn’t need to sleep or get bored with repetition, so it can go through images a lot faster than a person can. This way, we can get a baseline for our reefs now, and we will be able to identify when there’s a problem so that we can try and fix it before it’s too late.

I have installed the game on my tablet. It’s a lot of fun, and I find it to be really relaxing. Most people can play the game; it doesn’t matter if you’re in elementary school or have a grandkid in elementary school.

NeMO-net is a simple game that allows you to go on virtual dives and identify things on the reef or coastline. You gain experience with each picture you submit, and you slowly level-up your way up the food chain. You can also gain badges and achievements for playing the game.

The best part, in my opinion, is that the game comes with videos that you can unlock. There are video field guides on various creatures you see, how the technology works, and the process behind everything. There’s also written information on the various families of coral you can identify in the game.

NeMO-net is a great way to spend your time and to get into citizen science without any complex understanding of the ocean. And it also makes you feel like you are part of the NASA team; in my case, I feel just a little bit more important to the coral I want to protect.

Links:
https://www.nasa.gov/press-release/nasa-calls-on-gamers-citizen-scientists-to-help-map-world-s-corals/
http://nemonet.info/

Sea Whip

Domain: Eukarya
Kingdom: Animalia
Phylum: Cnidaria
Class: Anthozoa
Order: Gorgonacae
Family: Gorgoniidae
Genus: Leptogorgia
Species: Leptogorgia virgulata

I’ve realized that so far the only corals I have mentioned have been hard corals—reef builders. I will admit, that I like more hard corals than soft, but that doesn’t mean soft corals aren’t worth talking about. Continuing with my Chesapeake Bay theme, I’m going to talk about a native soft coral, the Sea Whip.

Cue the 80s music: “Crack that whip!” “Just whip it!”

The major difference between hard and soft corals is the composition of their bodies. Hard corals have permanent, rigid exoskeletons that house the coral polyps. These structures require large amounts of energy to build, which is why it can take a year for hard corals to grow just an inch, at best. Soft corals, however, lack that rigid calcium carbonate skeleton. Instead, soft corals are mostly made of living tissue that allows the soft corals to assume more creative shapes.

Sea whips, Leptogorgia virgulata, have long, thin branches that can grow up to a meter long. Their coloring can vary from red, to tan or orange, to purple. The polyps are always white, so sea whips look like they’re covered in white fuzz. Most soft corals are more colorful than their harder cousins.

Sea whips are found in reef environments and can tolerate low levels of salinity, so they are most common in nearshore areas that are more influenced by the tide. They range from New York to the Chesapeake Bay and from Florida to Brazil. In the Chesapeake Bay they thrive in the salty waters of the lower section of the bay.

L. virgulata are suspension feeders, so the polyps use their long tentacles to snag plankton and other tiny particles that are suspended in the water. When sea whips are born, the tiny polyps are carried by waves and currents. When they reach adulthood, so to speak, they become sessile meaning they cannot move from the hard substrate they land on. So they rely heavily on water circulation to stir up the water and bring in more plankton and nutrients for them to feed on.

I have yet to see a sea whip while diving, which is something I wish to change. But I wanted to share this soft coral to show that not all corals are found in tropical places, and that corals can be a lot more diverse than we think. And I’m happy to report that as of this writing, the populations of sea whips in the Chesapeake Bay and other monitored areas are considered stable!

Sources and more info:
https://www.chesapeakebay.net/discover/field-guide/entry/whip_coral
http://www.dnr.sc.gov/marine/sertc/octocoral%20guide/Leptogorgia_virgulata.htm
https://naturalhistory2.si.edu/smsfp/IRLSpec/Leptog_virgul.htm

Atlantic Mushroom Coral

Domain: Eukarya
Kingdom: Animalia
Phylum: Cnidaria
Class: Anthozoa
Order: Scleractinia
Family: Mussidae
Genus: Scolymia
Species: Scolymia lacera

Not all hard coral grow to be great big structures. And while most coral are considered to be a colony of polyps—i.e., individuals living together—there are some that are quite solitary. Some of them, like the cup corals, live a bit differently than their cousins and distant relatives.

Atlantic Mushroom coral, or Scolymia lacera, is one of a few cup corals found in the Western Atlantic Ocean. In fact, they occasionally can be found in deep-reef environments and on reef walls in the waters around Florida, the Bahamas, and the Caribbean. They prefer well-lit areas on rocky surfaces and outcroppings, somewhere nice and stable with enough light to help out their zooxanthellae friends.

S. lacera varies in color from shades of light gray to green, blue-green, and brown. The few that I have seen while diving were a mix of blues and greens, almost like an alternating stripped pattern—though this isn’t the same of all individuals.

Unlike other coral, the whole structure that is S. lacera is made up of a single polyp. That’s right; this species of coral is not a colony like its other hard coral cousins. Instead, it is a single large, fleshy, roundish polyp that looks a bit rough around the edges—texture-wise, that is. The whole structure that you see is the corallite, or the skeletal cup in which an individual polyp sits in and can retract into. For S. lacera, the center of the corallite can be either flat or curved inward; rarely is it seen with a raised center.

The Atlantic Mushroom coral can grow to between 2.5 and 6 inches and is the only type of cup coral that you can identify in person if it’s larger than 4 inches in diameter. Any specimen smaller than 4 inches has to have its corallite structure examined for identification.

During the night and in turbid, cloudy conditions, the polys will extend their tentacles in the hopes of grabbing food.

I think these guys are really cool because they break the mold, so to speak, when it comes to most hard corals. Instead of being a colony of individuals, each structure is a single large individual. They’re also pretty neat to spot on the reefs because they can be these bright colorful spots amongst drab shades. When I first saw them I didn’t think they were coral. It wasn’t until I started taking classes and we discussed them that I learned what they were.

Sources:
Reef Coral Identification: Florida, Caribbean, Bahamas 3rd edition Paul Humann and Ned DeLoach

https://coralpedia.bio.warwick.ac.uk/en/corals/scolymia_lacera <–At the time of posting this article, I hadn’t gotten the rights to share any photos of the coral, but you can see pictures of this species at the link–please take a look!

John “Charlie” Veron

Domain: Eukarya
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Hominidae
Genus: Homo
Species: Homo sapiens

I want to take the time to talk about the major people that have been involved in the various aspects of marine science. During freshman year of college, my very first class was spent talking about some of the influential people that helped to get us to where we are today, one being Aristotle and his recorded work in marine biology. So many people—naturalists, sailors, and scientists—have done so much for all of the fields in marine science that I didn’t know where to start, but I want them all to be known.

So I went back to why I started this blog, because I’m a coral enthusiast, and I wanted to share my love for them and their world with everyone else, which led me to Charlie Veron, a fellow coral lover.

Born in Sydney, Australia in 1945, Dr. Veron has spent his life dedicated to coral and their reefs, so much so that he has been dubbed the “King of Coral” or the “Godfather of Coral.” How did he earn such a title?

Dr. Veron is credited for formally naming and describing over 100 new species of coral and discovering about 20% of the world’s coral species. He’s worked in Australia, the Caribbean, and every major coral reef area in the world. Many of the species he has found belong to the genus Acropora, the same genus as the Elkhorn coral that I first spoke about!

He’s written several books, including a three volume series called The Coral of the World, and he’s authored more than 100 scientific papers. Even now, he hasn’t put up his hat at over 70 years old!

With the help of many colleagues, Dr. Veron is developing a free website based on his famous three-volume book on coral. The website is updated as information changes and is an amazing resource for students and researchers alike—and I can’t wait to start looking through it myself! He’s also actively campaigning on climate change, ocean acidification, mass bleaching of coral reefs, and so many related issues through interviews and documentaries.

I highly recommend watching some of the documentaries that he’s featured in. I got the chance to see Raising Extinction by Rob Stewart, in which Dr. Veron had had an interview, and he was so interesting to listen to. It’s nice to see that even at such an age, he still has so much love and conviction for the ocean, and I’m thankful for all that he’s done and is still doing. His work is inspiring, whether or not you’re interested in coral!

Sources and cool links:
Ocean: The Definitive Visual Guide made by the American Museum of Natural History
http://www.coralsoftheworld.org/species_factsheets/ (This is the website I was talking about!!!!!)
http://therevolutionmovie.com/index.php/biography/dr-john-charlie-veron/

Giant/Boulder Brain Coral

A boulder brain coral (Colpophyllia natans) growing on a coral reef. Photo taken by D. Alex Mustard, more can be found at www.amustard.com

Domain: Eukarya
Kingdom: Animalia
Phylum: Cnidarian
Class: Anthozoa
Order: Scleractinia
Family: Mussidae
Genus: Colpophyllia
Species: C. natans

First let me state that I have a love/hate relationship with common names. Most people call the Colpophyllia natans the Boulder Brain Coral; however, there are some texts and articles that call it the Giant Brain Coral. Why is this frustrating and worth mentioning? I spent a good chunk of time trying to confirm that these guys are the same species with different common names—I really didn’t want to make a fool of myself!

C. natans are named Boulder Brain Coral because they typically form large rounded structures that look like, drum roll please, boulders. They can also form large rounded plate-like structures, encrusting over rocks and existing coral colonies.

Like other brain coral, C. natans look like someone gave a chisel to a child and told them to go wild on the coral, creating a random pattern of valleys and ridges on the surface. A thin groove runs along the very top of the ridges, though you usually can’t see it when diving because you’re too far away (and if you’re not, you should be).

A second line is found halfway down the ridge where the angle decreases and slopes to create the valleys. The valleys are usually long and wandering, almost path-like, but sometimes they’re closed up and look more like individual cells squished together. The coral polyps are found within the valleys; the long ones containing multiple individuals, while the closed ones hold one or two polyps.

The ridges and valleys are normally different colors from each other. Ridges are either brown or gray while the valleys can be green, tan, or whitish.

You can commonly find them on reef tops or seaward reef slopes in the tropical waters of the Gulf of Mexico and the Caribbean. They can grow to have a diameter of up to 16 feet and can live as long as 100 years! C. natans are extremely popular tourist attractions, especially in the Florida Keys. But divers aren’t the only things these guys attract; they also attract all kinds of fish, including some gobies that live permanently on the coral.

I’ve only ever seen these guys during day dives—which, trust me, is still really cool to find them because of their size and coloring. However, they’re even better to see on a night dive because that’s when the polyps let out their tentacles to fish for zooplankton. I’ve been told that the coral can look completely different at night, and I can’t wait to see it for myself in person!

Sources and cool links:
Coral Reef Identification: Florida, Caribbean, Bahamas 3rd Edition by Paul Humann and Ned DeLoach
Ocean The Definitive Visual Guide made by the American Museum of Natural History
http://species-identification.org/species.php?species_group=caribbean_diving_guide&menuentry=soorten&id=305&tab=beschrijving
http://www.coralsoftheworld.org/species_factsheets/species_factsheet_summary/colpophyllia-natans/
https://www.sealifebase.ca/summary/Colpophyllia-natans.html
http://www.wildernessclassroom.com/wilderness-library/giant-brain-coral/

Symbiosis

I just wanted to take a quick moment and talk about symbiosis. I know it’s a topic you learn about in school; I first learned about it in middle school, then again in high school biology, and then a few more times in college. If you already know about symbiosis feel free to pick another post from the sidebar or glance over this one for a quick refresh. For those of you who haven’t learned about it yet or have simply forgotten, I’ll try to explain it in the best way possible—through the human experience!

There are many forms of symbiosis that we see and experience every day, but first let me explain what it is.

Symbiosis is any long-term and personal relationship between two or more individuals, and the relationship can be between the same or different species, such as between you and another human or a pet. Each participant in the symbiotic relationship is called a symbiont.

There are different types of symbiosis that are defined by the kind of interactions between symbionts. If you’ve read my post about coral and zooxanthellae, you’ve already been introduced to a form of symbiosis called mutualism. In a mutualistic relationship, such as coral and zooxanthellae, both parties benefit without inflicting harm on each other. Think of mutualism as the relationship you have with a project partner: if done right you both benefit from each other’s hard work. It can also be viewed in a relationship between humans and dogs or cats: the animal gains a home and a reliable food source while, the human gets companionship and additional health benefits.

A female oceanic whitetip shark (Carcharhinus longimanus) is accompanied by a group of pilotfish (pilot fish: Naucrates ductor) as it swims overhead. Photo taken by Dr. Alex Mustard, find more of his photos at www.amustard.com

Commensalism is a type of symbiotic relationship wherein one individual benefits and the other remains unaffected. An example of this is the pilot fish that ride on or near sharks or larger fish: the pilot fish feed on the leftovers of their hosts while the hosts remain unaffected. In the human experience, it’s like when you let a classmate copy off your homework: you gain nothing while they get all the right answers.

Not every relationship is healthy though. And this last relationship may be disturbing for some people.

Parasitism occurs when the parasite benefits from the host and the host suffers. An example of this relationship can be found in all species of parasitic wasps. The wasp will find another insect (caterpillars, spiders, other wasps, etc.), paralyze them, and then lay their eggs inside the host. The host will then go about the rest of their lives while incubating the eggs, and when the eggs hatch, they burst from the host like a scene from the movie Alien. And sometimes the host will survive only to protect the hatchlings until the host dies of starvation. This is an extreme example, but one of the more fascinating ones I learned about in one of my ecology classes. In human terms, parasitism is like the one cousin (or friend) that always comes to you asking for money and claiming they’ll pay you back but they never do.

Mutualism, commensalism, and parasitism are the main types of symbiosis. There are others that I will probably mention as I talk about the various other species, or if I want to dedicate another post to symbiosis. I know it’s a lot of word vomit, but I hope I made a bit more palatable than standard textbook explanations. Personally, I find symbiotic relationship like parasitism really interesting, especially with parasitoid wasps. I could easily see myself studying the wasps that may have inspired the Xenomorphs from Alien in an alternate universe!

In another alternate universe, I think I’d dedicate my life to researching sloths too. Sloths are maddeningly adorable, I could spend hours watching them. I wish there was a way to watch what my alternate selves were doing with their lives. Wouldn’t that make for some fun reality TV!

Coral part 2

Photo taken by Dr. Alexander Mustard. You can find more of his amazing photos on his website www.amustard.com

Last time, I mentioned all the factors that determine a coral’s success in an area, and most of those factors relate to hard coral or reef building coral. Soft coral are a bit different from their constructive cousins; for instance, they don’t all rely on zooxanthellae, and so most of this information pertains to hard corals—but don’t worry, I’ll get to soft corals eventually!

For hard coral, the factors that affect their success in an area include water temperature, salinity, depth, water circulation, and clarity.

Most of these factors aren’t hard to explain because we can relate to them. For instance, we don’t like to be too warm or too cold. It’s the same with coral: they don’t like their water to be too warm or too cold, so their ideal range is between 85°F‒70°F. This is not a very strict range because there are reefs and species found outside these temperatures, but for the most part this is important for reef-building coral.

Hard corals also don’t like their water to be too fresh or too salty. They prefer their water to have a salinity level between 30 and 40 parts per thousand (ppt).

Next, we’ll talk about water circulation. This one is really important because coral can’t move elsewhere once the food is gone, they’re sedentary. They’re not like humans, who can get off the couch and grab food when they’re hungry. Coral pretty much have to be in an area that always has food—so it’s like if your cousin decided to live in the supermarket for the rest of their life. Coral feed on zooplankton, which for now let’s describe as plankton-size animals, and that means that the coral’s food isn’t regularly replenishing. Instead, coral rely on water circulation, either through water currents or wave actions, to stir up the water and bring nutrients and food to them. Without good circulation, coral can easily starve, even the hard coral that obtain most of their energy from zooxanthellae.

The final two factors determining coral survivability are especially important to hard coral because of their partnership with zooxanthellae, and these factors are related to sunlight: water clarity and depth. Water clarity is defined by how clear the water is. If the water is really cloudy and full of particles, then the zooxanthellae may not be able to receive enough light for photosynthesis. Depth has similar effects: sunlight can only penetrate so far into the ocean before the only visible light comes from bioluminescent creatures. If the coral is anchored too far from the surface, then the zooxanthellae may not get enough light and the pair can die.

There are coral that can survive outside of these factors; for instance, they have discovered coral in the deep ocean at depths of 6,000 m (20,000 ft)—that’s almost four miles below the ocean’s surface. Deep-sea coral are fascinating because they vary from their shallow-water relatives, but I’ll get to those later.

If the hard coral’s habitat changes beyond these set factors, then it can have devastating impacts on the organism. If the conditions don’t return to the normal, then the coral will expel their zooxanthellae in a process called Coral Bleaching. Some research has suggested that the coral can reacquire their zooxanthellae or even acquire new zooxanthellae. However, there are still a lot of unknowns in regards to Coral Bleaching and coral health, which is why continued research is so important!

If the coral die then the reef dies, and from there it’s a domino effect that will very quickly impacts us. Without the reefs the world fish populations will dramatically decrease. Less fish means less food for the animals that live in the ocean, and less fish for us as well. If we compete with creatures like dolphins and whales for food, then those populations of animals will dramatically decrease as well. All in all, coral reefs are the rainforests of the sea in terms of biodiversity, habitat, and oxygen production.

It’s not all desolate and hopeless. There is research being done through the field of aquaculture in trying to grow coral ourselves to help save the reefs, most of which are being done at aquariums and universities. Researchers are trying to figure out ways to preserve the reefs that we have now, and to protect them from further climate-change-inflicted damage.

However, a grim-looking future faces us if we can’t curb the effects of climate change on our oceans, and that’s why YOU are so important in this struggle too. Everything you can do, big or small, to saving energy and reducing plastic use to conservation research programs will help lessen the impact of climate change and preserve our reefs for future generations.

Zooxanthellae

If you’ve ever had the opportunity to dive or snorkel at a coral reef, you might’ve seen impressive coral structures. In Jamaica, I saw massive Boulder Coral, Acrapora species (like the Elkhorn Coral) that looked like alien trees, and Pillar Coral that appeared to be the main feature of the reef, from the perspective of a photographer.
In fact, if you look at pictures of reefs online, a lot of them have huge corals that draw the eye. Now, how do coral get that big? They only eat plankton and there’s only so much one can eat in a day, but they require a lot of energy for everything they do. Lucky for the coral, at least the reef building varieties, they don’t have to acquire all that necessary energy by themselves.
Let me introduce you to what is, in my opinion, one of the best examples of a mutualistic relationship in the animal kingdom. High on the to-do list of most coral polyps is to acquire the best of best friends in the ocean, zooxanthellae (zo-zan-THEL-ee).
This organism, or group of organisms, is a type of dinoflagellate (a special kind of algae) that forms a positive symbiotic relationship with creatures like coral and jellyfish. A symbiotic relationship is defined as any relationship between two or more individuals of the same or different species that lasts over an extended period of time. You and a pet have a symbiotic relationship.
For coral and zooxanthellae, they’re like best friends; not only do they live together, but they help each other, making it a mutualistic relationship. In exchange for a safe haven from predators like zooplankton, and necessary ingredients for health and photosynthesis like carbon dioxide and nitrogenous waste products (they eat coral poop), the zooxanthellae give coral their excess food.
That’s right, zooxanthellae are like those friends that bring huge amounts of food to your party or potluck and leave the leftovers with you, giving you meals for days. In fact, zooxanthellae provide up to 90% of the energy needed for coral growth and reproduction; they are the reason those Pillar Coral can grow as tall as you are and why coral reefs exist.
In summation, zooxanthellae are friends, not food! No, wait; that’s not quite right. Zooxanthellae are totally the friends you want to have in order to build a successful community, or if you want to mooch off their leftovers because you can’t make enough food on your own.

Coral (part 1)

Photo taken by Dr. Alexander Mustard, find this image and many others on his website http://www.amustard.com/

When I first started reading about coral I never thought I’d want to study them. While they looked really cool and fascinating, they didn’t hold a candle to dolphins or sharks to my 8-year-old self. It wasn’t until I was older that I realized that there was more to them than appearances suggested.

Do you believe coral to be rocks, plants, or animals? Some of them appear to be very dull in color; this is especially true for some of the coral found in the Atlantic Ocean, which have various shades of brown or drab green. While some may look like rocks, I’m talking about you Boulder Coral, coral are most definitely not rocks because they feed and grow over time.

If they’re not rocks, then that makes them either plants or animals. Well, coral don’t really have legs, and we’ve never seen them move from point A to point B. In fact, they’re very much rooted to their spots and only move by swaying with the waves. So by this logic, they’re plants, right? They have no noticeable organs and they don’t have any independent movement. Until the early 1750s, they were classified as plants. It wasn’t until a French biologist, J.A. de Peysonell, determined that they were animals when he was completing a study of the Western Atlantic in 1753.

Coral are animals that belong to the Phylum Cnidaria, along with jellyfish and anemones. Like their cousins, coral have tentacles that they use to capture food. Coral also reproduce asexually, which allows them to expand and colonize an area.

All coral need is a good surface to attach to because once they land they can’t move locations, so real estate is very important to coral polyps. Good places for them are large rocks or other hard surfaces, like sunken ships, stone statues, or other man-made things, that won’t be easily moved during a storm or rough water action. If the coral’s substrate tips over or shifts, it can disrupt and hurt the coral, possibly leading to death.

They are very sensitive to their surroundings, requiring specific conditions for them to grow optimally. Those factors vary between the groups of coral, but if the conditions aren’t met then the coral may not grow. Worse yet, it can die.

Now, I can ramble on for hours about coral and everything about them that I find fascinating. However, I don’t want this to be like those long academic research papers that put insomniacs to sleep. So I’ll share the information with you in little bursts as I blog.

Source: Humann P, DeLoach N. 2013. Reef coral identification: Florida, Caribbean, Bahamas. 3rd ed. Jacksonville, Florida: New World Publications.