Snorkeling

You don’t have to leave the planet to experience an alien world. Nature is always full of strange, otherworldly creatures and places that just exceed all imagination, and inspire mythes and legends all around the world.

I first experienced something so alien when I was in elementary school. My parents were fortunate enough to afford a trip to the Caribbean and they wanted to take me snorkeling.

I’ve always been told that when I first experienced the ocean as a toddler that I wanted nothing to do with the water. My dad always had to put me on his shoulders before I could get close to the ocean. Apparently, I had decided that my mom wasn’t tall enough to protect me from the waves. So it was a bit of a surprise to my parents when I took to the ocean so well.

It was a magical experience because the reef was so healthy and colorful. There were fish of all shapes and sizes. Everything caught my attention and I never stayed in one spot for too long, which might’ve exhausted my parents a bit trying to keep up with me.

It was this experience that made me want to learn more about the ocean. It was so weird, so alien! I could see out into the open ocean for miles. There were strange sounds, little clicks, pops, and crunches that followed me everywhere. Why were the rocks so brightly colored? Why did they look so funny? What were all these fish?

My curiosity exploded and I needed to know everything I could about the ocean.

Snorkeling is an amazing experience for anyone willing to give it a shot. Not every reef can be viewed by snorkeling, but there are plenty of options off the coast, especially in the tropics.

I highly recommend it for anyone wanting to experience the ocean, but isn’t quite ready for scuba diving. Snorkeling can be very relaxing. Some places allow you to do it by yourself or you can go with a group.

Always do some research before you go snorkeling. Some places provide gear, others don’t. There also may be special rules and regulations that you should follow to keep the reef clean and healthy, like some places require a special kind of sunscreen that is less harmful to coral. Later, I’ll follow up with a post on the behaviors that all snorkelers should follow to help keep the reef and themselves safe, while still having a good time!

The next time you visit a coastal destination, see what kind of ocean opportunities are available. If there’s snorkeling in the area, give it a go and see what you can find! You can find cool shells, shark teeth, or items swept away by storms like glass bottles. Not to mention all the local fish, some may seem normal while others are out of this world!s

Upwelling

When I talked about the Gulf of Guinea, I mentioned that it was a site of coastal upwelling. There are different kinds of upwelling, depending on how the process occurs. Upwelling can occur off the coast or in the open ocean. Today, I’m going to give a general overview of upwelling.

Upwelling is a process in which deep, cold water is brought to the surface of the ocean. Upwelling occurs when wind pushes the surface water away, allowing the deeper water to rise to the surface. This cold water is typically full of nutrients that are vital for seaweed and plankton growth, creating areas of high productivity.

In this nutrient-rich water, seaweed and plankton population increases drastically, which sets off a chain reaction. The large amount of seaweed attracts herbivorous fish, and the large amount of plankton attracts filter feeders and small fish. Larger fish are attracted by all the small fish. Sharks, dolphins, and even sea birds are attracted by the large amounts of fish in the area.

Areas of upwelling are very important to both the ocean and to humans.

Upwelling provides food for all kind of fish, marine mammals, and sea birds. Think of the open ocean as a desert. It’s so vast and deep that it could be days before a dolphin or a shark can find their next meal. Areas of upwelling in the open ocean are like an oasis, especially for migratory animals who might not encounter a lot of food on their long journeys.

Coastal upwelling covers about 1% of the world’s oceans, but it provides about 50% of all our harvested fish. Some of the most successful fishing grounds occur in or around areas of upwelling. And when something happens and the upwelling stops, like in an El Niño weather event, the fishing industry takes a heavy hit, harvesting fewer and smaller fish.

Upwelling is so important that scientists and businesses are joining together to try and figure out how to create artificial upwelling using technology. So if you’re looking for a job in something groundbreaking, look into artificial upwelling! I have a feeling that it’ll be an important endeavor for years to come.

Sources and links:
https://oceanservice.noaa.gov/facts/upwelling.html ⇐ brief look into upwelling
https://www.nationalgeographic.org/encyclopedia/upwelling/ ⇐ more in-depth view of upwelling and coastal upwelling
https://oceanexplorer.noaa.gov/explorations/02quest/background/upwelling/upwelling.html

Common Names

I’ve mentioned for a while now that I have a love/hate relationship with common names. They’re great to use in conversations with people outside of the science community, and they’re typically a lot easier to say too. Not everyone will know the scientific name of organisms. Honestly, I don’t know all the scientific names of all the organisms that I like.

One of my issues with common names is that they can be misleading.
When I was growing up, we were taught that those star-shaped creatures that stick to rocks were called starfish. When I entered college, everyone was pushing the name sea star. Why the change in common name?

The common name starfish led people to believe that those creatures were a species of fish. Instead, they are from a completely different phylum of organisms called Echinoderms; the two echinoderms and fish have very little in common. Misinformation can be a very dangerous.

When you look up the term dogfish, you get information on several different species of sharks. Dogfish shark is the common name given to the shark family Squalidae. Each species in this family are small, about 4 feet long. They are found in both tropical and temperate waters, along the coasts and in the deep open ocean. Each species can be referred to as a dogfish, which has unfortunately been a disaster for them.

Most species of dogfish are taken heavily by the commercial fishing industries, and a lot of them are threatened or critically endangered. The problem is that commercial fisheries are told they can take x-number of dogfish per season, but the regulations don’t specify what species of dogfish shark can be taken.

Some species of dogfish shark only produce one offspring per year, while others can produce twenty. Some species of this family can live up to a hundred years, so their age of sexual maturity is a lot older than those who have a shorter life span. It’s the species that have an older age of sexual maturity and a low offspring rate that are suffering the most.

I understand that it is hard to tell one species from the other, and by the time you decide that you got the wrong dogfish, the creature might already be dead. What I am saying is that lawmakers need to be more specific with their regulations, or else we’ll accidentally cause the extinction of several species because they all have similar names.

This is an extreme case, but it’s still an important one to point out. Common names are great in conversations and educating people in ways that they’ll better understand. However, common names need to stay out of regulations and policies to eliminate any confusion.

Anemones

A close up of jewel anemones (Corynactis viridis). Photo by Dr. Alex Mustard, more can be found at www.amustard.com

Domain: Eukarya
Kingdom: Animalia
Phylum: Cnidaria
Class: Anthozoa
Order: Actiniaria

I have often heard people refer to sea anemones as flowers or sea flowers, and I always wondered why. Apparently, these organisms gained their common name because their bright colors reminded people of the terrestrial anemone flower.

It makes sense why people would consider sea anemones as flowers. Sea anemones don’t appear to move, they’re brightly colored, and their tentacles can resemble petals. However, like their coral and jellyfish cousins, sea anemones are animals.

A sea anemone is a single large polyp that lacks any skeletal structure and contains stinging cells called nematocysts. They have cylindrical bodies that are attached to hard substrates by their adhesive pedal disk, or foot. Its mouth, or oral disk, rests near the top of the body and is surrounded by tentacles, which they can retract into their body when feeling threatened.

Sea anemones come in all shapes, sizes, and colors. There are over 1000 species that range from half an inch wide to over 6 feet wide. They appear in various shades of blue, green, yellow, and red. Many species are more than one color or shade; often, the tentacles can be a different color than the body. Species in warm tropical waters are often larger and more colorful than sea anemones found in deeper, colder water.

Sea anemones are found in every ocean. They can be found at various depths, from shallow water to over 3000 meters deep in the ocean. They inhabit various crevices of coral reefs, rocky substrates, and sea walls. Some have been recorded on the backs of sea turtles.

Sea anemones are carnivores. They feed on planktonic organisms, crustaceans, small fish, and occasionally mollusks and sea urchins. The tentacles of sea anemones are used in defense and for capturing food. These stinging tentacles are touch sensitive. When potential prey brush up against the tentacles, harpoon-like filaments, called nematocysts, are launched at the prey. The nematocyst hooks into the prey and releases a neurotoxin that paralyzes the creature, then the tentacles pull the prey to the oral disk to be consumed.

Some organisms are immune to the stinging tentacles and coexist with various species of sea anemones.

Many people are aware of clownfish and their mutualistic relationship with sea anemones. Clownfish have a unique adaptation that allow them to live within the tentacles of the anemone. The sea anemone provides protection for the clownfish, and the clownfish will keep the anemone clean and lure potential prey to the anemone.

Other symbiotic relationships with sea anemones include various small crustaceans and zooxanthellae.

The stinging tentacles of the sea anemone don’t protect it from every organism. Various species of starfish, sea slugs, eels, and some species of fish prey upon anemones. Occasionally, sea turtles have been recorded munching on sea anemones when given the chance.

I don’t believe there is a Cnidarian that I don’t find fascinating. At the aquarium where I volunteer, there’s an exhibit that shows how some sea anemones rely on wave action to supply them with food. It’s one of my favorite exhibits because it’s so bright and colorful, and I find it relaxing to watch. Every few minutes, the exhibit simulates incoming waves, and you can watch the water whooshing down toward the sea anemones.

Sources and links:
Reef Creature Identification Florida Caribbean Bahamas 3rd edition by Paul Humann, Ned DeLoach and Les Wilk
Ocean: A Visual Encyclopedia (Smithsonian) by John Woodward
https://www.nationalgeographic.com/animals/invertebrates/group/sea-anemones/
https://www.britannica.com/animal/sea-anemone
https://aqua.org/Experience/Animal-Index/anemones
https://animals.net/sea-anemone/

Hope Spots

Twelve percent of the world’s land is under some form of governmental protection, such as reserves and national parks. The ocean makes up seventy percent of the earth’s surface. Of that seventy percent, less than five percent of the ocean is protected in any way.

That’s where Mission Blue comes in.

Mission Blue is an organization created by the oceanographer Sylvia Earle. Their mission is to create Hope Spots around the world, and their goal is to more than double the percentage of protected waters.

Hope Spots are areas of the ocean that are important to its health. These areas are special because they may harbor unique or delicate ecosystems and habitats, such as coral reefs or gulfs. Hope Spots can also be sanctuaries for endangered species or species that are only found in that area. They can also provide services to the ocean that are vital to marine life, such mating grounds and nurseries.

Hope Spots can also be historical to the community, or they may hold spiritual or cultural importance. They can be areas that could potentially help curb the effects of climate change. All in all, they are important areas not only to the ocean and its inhabitants, but to humans as well.

The best part about Hope Spots is that YOU can nominate them. On the Mission Blue website, you can nominate a local area as a Hope Spot.

Let’s say, for example, that I nominate the Chesapeake Bay as a Hope Spot. Using various forms of media, Mission Blue would increase the visibility of the bay and its importance. Mission Blue would help connect me with potential partners for the project and help set up expeditions to prove the bay’s importance to the community. Mission Blue would also help advocate for legal protection of the Chesapeake Bay, which in this case would be advocating to at least Maryland and Virginia state governments.

By allowing people to nominate their own Hope Spots, they essentially help to give people hope and to empower communities. People are more likely to fight to protect something if you give them the power to do so.

But why should we care?

“Health for the oceans means health for us.” –Sylvia Earle

Humans owe so much to the ocean, whether we live on the coast or high up in the mountains, hundreds of miles away. Many of us consume fish, mollusks, seaweed, and crustaceans that are harvested from the ocean. Not to mention what goes into some of the food products for our pets and livestock.

Not only does the ocean provide us with food, but it plays a part in our climates and the weather. The ocean currents of the world affect the climate as they redistribute heat from the equator to the poles.

Then there’s the air we breathe. The algae and phytoplankton in the ocean produce more than half of the world’s oxygen, more even than the Amazon Rainforest!

No matter where you live, the ocean impacts your life on a daily basis. Therefore, we need to care for the ocean like we care for ourselves and you can do that any way you feel comfortable doing.

If you can donate to special organizations like Mission Blue or World Wildlife Fund—fantastic! If you can volunteer at aquariums and other aquatic groups or participate in citizen science such as using the NeMO-net video game to help researchers identify and protect coral, that’s wonderful. If you can find ways to decrease your carbon footprint and/or plastic use, that would be amazing. If all you can do is talk about these things to your friends and family and take these topics to social media, that’s beautiful too!

It’s time to bring back hope one step at a time!

Sources and links:
https://www.worldatlas.com/articles/what-percentage-of-the-world-s-ocean-area-is-protected.html
https://mission-blue.org/hope-spots-faqs/ ⇐more info on Hope Spots
https://mission-blue.org/act-now/ ⇐things you can do to help the ocean. Remember, these are suggestions!

Law of Refraction

My husband’s late grandfather was a fascinating man and a brilliant engineer. When I first met him, he asked me if I knew about Snell’s law. At the time, I was still in college and hadn’t taken physics yet, but it sounded familiar. When he started to explain it to me, I recognized it as the law of refraction. I remember his eyes lighting up when I caught on. Later, I learned that it was one of the ways he judged a person, and he had deemed me worthy.

I bring up this physics term because it also relates to water.

The easiest way to explain Snell’s law is with a physical example.

Take a smooth, clear glass and fill it full of water. The glass or cup can’t have any ridges or funky shapes in the glass, or the demonstration might not turn out right. A pub-style pint glass works well. Next, find a straw or a pencil—I recommend an eco-friendly steel or biodegradable paper straw—and put it in the water. Now, spend some time looking at the glass from different angles. Look from above and at eye level with the water line, and move the straw around.

What you should see is that the straw doesn’t appear perfectly straight. Sometimes the submerged half of the straw seems slightly thicker. Sometimes the two ends don’t line up, and there may be a slight bend in the straw that isn’t actually there. From above the end of the straw might look a little curved to one side.

The law of refraction governs how light bends or refracts as it passes from one medium to another, like from the air to the water. This law explains why things are not always where they appear to be in the water as seen from the air.

Luckily for us, we have a straight forward equation we can use figure out the refracted angle, though you may need to do some more independent reading to understand why it works. Other creatures don’t have mathematical formulas to help them, though.

For example, an osprey flying over a body of water will have to learn how to accurately find its prey underwater or it will starve. From the air, a fish may appear to be in one spot but may actually be a few feet to the right. If the osprey misjudges where the fish is the first time and doesn’t catch it, then its chances of getting a fish the second time are greatly reduced because it lost the element of surprise. Birds of prey must learn to adjust to this optical illusion, a failed attempt at catching prey is a waste of energy.

Another example is the Australian archer fish, a fish that has developed the ability to spit jets of water at bugs on overhanging tree branches. Archer fish learn to do this because during the drought season, their normal food supply may become scarce, so they spit at bugs to try and knock them into the water to eat.

The same distortion exists for the archer fish below as it does for birds from above. The bug that the archer fish wants to knock off its branch may actually be three inches to the left instead of straight above the fish. So, through trial and error, archer fish learn to calculate where the bugs are above the water.

At the aquarium I volunteer at, one of my favorite activities is talking to guests about the archer fish’s ability to spit water at bugs on overhanging branches. Occasionally, we’re allowed to demonstrate this by getting a live cricket on a stick that we extend over the exhibit. Very quickly, little jets of water are arching out of the water as the fish try to knock the cricket into the water.

The fish that successfully hits the cricket isn’t always the one to eat the cricket. In fact, sometimes the pig-nose turtle in the tank gets the cricket. And sometimes, the volunteer (reads as: me) doing the demonstration gets spit in the face by the archer fish. But who can get mad at that? It actually made my day!

Sources:
https://www.physicsclassroom.com/class/refrn/Lesson-2/Snell-s-Law
https://www.math.ubc.ca/~cass/courses/m309-01a/chu/Fundamentals/snell.htm
https://www.britannica.com/science/Snells-law

Invasive Species

Invasive is such a harsh word. How can a natural creature be considered an invasive species? Nobody likes weeds, but everyone likes pretty fish and colorful birds—so, how can those be considered dangerous?

An invasive species is any living organism that is found outside of their native environment and has or will cause harm. The harm it can cause can be to the nonnative environment itself, the economy, or humans, or a combination of the three.

The zebra mussels that I’ve spoken about are an example of an invasive species in the United States. They are native to the freshwaters of Eurasia but somehow made it to the United States in the 1980s. Wherever the zebra mussels have been found, outside of Eurasia, they have outcompeted all native species and have changed the environments that they have invaded.

Another example is the lionfish. Its native habitat is the Indo-Pacific Ocean, however, it has made its way to the Atlantic Ocean. It reproduces rather successfully and has no natural predators in the Atlantic waters, so it has decimated many coral reef populations by devouring the herbivorous fish that help keep the reefs clean of algae. Without the algae eaters, the coral are smothered by the thick blankets of algae that naturally grow on them.

Not all invasive species are easy to comprehend at first. For instance, in many countries, domesticated cats and dogs are considered to be invasive species. How can Mittens or Spike be considered invasive? Humans absolutely love them and they (mostly) love us!

Dogs, and especially cats, are considered invasive species in many countries outside of Europe. They were brought over during the time of colonization, and their populations quickly grew unchecked. Dogs threaten native small animal populations, and cats wreak havoc on the native bird populations. For example, the Galapagos penguin population has been hit hard by the invasive house cat populations in South America.

Invasive species don’t have to look exotic. Sometimes they look normal, or they’re hard to notice at all. Invasive species can include plants, animals, fungi, insects, and microbes. And their effects on the local populations can be devastating, as when settlers first encountered native people, and the germs the settlers brought with them killed a lot of the native people of the land who did not have the same immunities built up as the settlers did.

Invasive species can also cause harm in other ways. New microbes introduced to an area can cause illness in people. Insects that have hitchhiked in shipping containers can run wild in new places and hurt the people there, like invasive species of hornets or spiders. Invasive jellyfish can fill the waters and harm beach goers.

Invasive species can even cause harm economically. Invasive hornets destroy beehives that produce honey to be sold. Zebra mussels clog pipes and encrust boats; it costs a lot of money to remove them, and it’s usually not a one-time expense. Lionfish have made coral reefs barren, reducing the populations of game and harvestable fish to low numbers, and impacting aquatic tourism.
Luckily, there are ways to handle invasive species. The best way is to prevent them from entering delicate ecosystems that they don’t belong to. For humans, that means being more careful when transporting food and supplies over long distances. It means finding new owners for exotic animals when you no longer want or can care for them—don’t just release them into the wild!

There are also ways to reduce invasive species numbers. For instance, many places around Florida and the Caribbean offer cash prizes for lionfish through spear-hunting competitions. Or you can encourage local chefs and restaurants to serve invasive species on the menu. The National Aquarium in Baltimore, Maryland frequently serves invasive fish in their diner.

I’ve eaten lionfish, and it’s pretty tasty! Mine was served Jamaican style, featuring a lot of spices that I wasn’t used to, but if prepared properly, it’s a great fish to eat. I’ve also had invasive catfish that was found in our local waters, and it didn’t taste that different from the native catfish, just maybe a little sweeter. So there are all kinds of ways to deal with invasive species, but it’s up to us to keep them in check!

More information:
https://www.britannica.com/science/invasive-species
https://www.nwf.org/Educational-Resources/Wildlife-Guide/Threats-to-Wildlife/Invasive-Species
https://www.invasivespeciesinfo.gov/
https://www.livescience.com/64533-lionfish.html

Sponges pt.1

A yellow tube sponge (Aplysina fistularis) growing on a Caribbean coral reef. Photo taken by Dr. Alex Mustard. More can be found at www.amustard.com

“Oooooooooooh! Who lives in a pineapple under the sea? SPONGEBOB SQUAREPANTS!”

Actually, pineapples are terrible places for sponges to live. If SpongeBob wanted the best place to survive and be successful, he would have lived on top of Patrick’s rock. I know, I know, it’s a show for kids and therefore isn’t accurate, but what better way to introduce the topic than with a relevant pop culture reference?

I just have to say that sponges are weird.

Like coral, they were first thought to be plants, which to be fair is quite understandable. Sponges don’t possess appendages, eyes, noticeable mouths, or reproductive parts, so if I had come across my first sponge without knowing its biology, I would have thought it was a plant too.

Sponges are the simplest multi-cellular creatures of the animal kingdom, and they’re so cool that they have their very own phylum, Porifera. In fact, sponges are so unique that they have no other close relatives.

Like other marine invertebrates, such as coral, barnacles, and oysters, sponges will permanently attach themselves to hard surfaces like rocks or shipwrecks. Some species of sponge will even burrow themselves into whatever substrate they want to call home. Once they’ve attached, there’s no second guessing, so hopefully they picked a good spot!

Unlike coral, sponges are a bit hardier and have fewer requirements to be successful. Sponges can live in a variety of different places that vary in temperature, salinity, and depth. About 2% of sponges can live in freshwater!

Sponges can be found almost everywhere: on rocks, shipwrecks, and coral reefs; they can be found in the tropics and higher attitudes, though a good portion of them live in Antarctic waters. Unlike coral, sunlight is a limiter for sponges. Too much sunlight exposure can be harmful for sponges, so they tend to prefer caves, crevices, and other places that don’t get a lot of direct sunlight.

However, there are a lot of sponges that live in areas with a few feet or less of water above them and in direct sunlight. These sponge species possess a special relationship with a species of algae that will dwell in the sponge. The sponge protects the algae from herbivores while the algae secretes pigments in the outer most layer of the sponge. These pigments act like sunscreen, thereby helping to protect the sponge from the sun.

Like most animals, a good place for a sponge to live will have a steady supply of food. Areas with strong tidal currents can support large sponge populations because all that water movement brings in extra food. Like whale sharks, sponges are filter-feeders, but how they feed is a bit more complicated. I will therefore have a whole post dedicated to how sponges eat!

For being the simplest multi-cellular animals you can find, sponges can be very complicated. I’ve barely scratched the surface of what make sponges unique and what they can do for their environments. But like all things, it wouldn’t be fun or interesting if it were easy!

Sources and fun links for those who want to dive right in to sponges:
Ocean: The Definitive Visual Guide made by the American Museum of Natural History
https://www.britannica.com/animal/sponge-animal#ref32631
http://www.oceanicresearch.org/education/wonders/sponges.html
http://tolweb.org/treehouses/?treehouse_id=4291
https://oceanservice.noaa.gov/facts/sponge.html

Water Bears

Water bears, or Tardigrades, are microscopic organisms that belong to the animal kingdom. However, they are not a single species. In fact, they’re a whole phylum that consists of over 1000 species! Honestly, I didn’t know that until I started researching them and now I know too many cool things about them to keep to single post. I’m sorry?

There’s so much to talk about when Tardigrades are the subject, though not as much as coral when I’m the one speaking! Let’s start with some general characteristics.

Water bears range in size between 0.05 a 1.2 mm, though the average water bear is about half a millimeter. In other words, they range from “extremely tiny” to “really tiny,” but their average size is “really really tiny.” You can’t see these guys with the naked eye except under specific lighting conditions. Most of us need to use strong microscopes to spot them.

What your microscope will show you is a really freaky but cute close-up of these eight-legged animals with nightmarish claws at the end of each leg. Unlike other microscopic organisms with appendages, Tardigrades have their legs positioned beneath them, which they use them to crawl around their environment. In fact, their name originates from a Latin word meaning “slow walker” because they move at a much more leisurely pace than the rest of the microscopic community.

Now, what do they move slowly to do? They feed on algae, lichen, and moss—well, more specifically, they suck the fluids out of them like vampires. Oh my, they’re adorable little vampires of doom for photosynthesizers!

Their prey lives in very moist environments. Water bears can be found on damp moss, in the sediment at the bottom of a lake, or even between grains of sand in marine sediments. Most Tardigrades are fresh water species, but there are some that can live in salt water environments. Water bears can pretty much survive in any condition, and researchers speculate that they will survive long after our bones have turned to dust!

I first learned about these guys at a sci-fi convention when I was looking for a toy to give to the small child of a family friend. There was a vendor selling microbe plushies with cool facts on the tags, and the water bug was one of them. The kid absolutely loved the plushie, and I found a favorite microbe that day!

Sources and cool links:
https://www.livescience.com/57985-tardigrade-facts.html
https://www.americanscientist.org/article/tardigrades

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!