Panama is a country where you can walk through the jungle and encounter things that look as though they belong in a dinosaur documentary. You can find sloths hanging above your head, monkeys shouting from the canopy, tarantulas hiding under logs, snakes disappearing through the leaves and crocodiles lurking in rivers.
And then there are fire ants.
They are tiny.
They weigh practically nothing.
You can crush one without even noticing.
And yet, if you accidentally stand on the wrong patch of ground, a few hundred of them can turn a perfectly pleasant afternoon into an experience you will remember for a very long time.
Fire ants are one of those small details of tropical life that visitors to Panama sometimes discover the hard way. They aren't necessarily the biggest or most frightening creatures in the rainforest, but they are an excellent reminder that in Panama, size and danger don't always have much to do with each other.
First, what exactly is a fire ant?
"Fire ant" isn't actually the name of just one species. Several ants in the genus Solenopsis are commonly called fire ants.
One particularly famous species is the red imported fire ant, Solenopsis invicta, a South American species that has become invasive in various parts of the world. But Panama also has other members of the fire ant group. For example, Solenopsis geminata, commonly called the tropical fire ant, is a widespread tropical species native to Central and South America. Panama's ant fauna is remarkably diverse, with hundreds of recorded species.
That distinction matters because not every ant that someone calls a "fire ant" is necessarily the same species.
In other words, if you see a tiny reddish ant in Panama and immediately announce that you've discovered a red imported fire ant, you may want to hold off on publishing the scientific paper.
The important thing for a traveller is simpler.
Some ants in Panama can deliver a very painful sting.
Why are they called fire ants?
There is no great mystery here.
They hurt.
The sting can produce an intense burning sensation, which is where the name comes from. Imported fire ants are capable of stinging repeatedly, and their venom can produce painful reactions.
The interesting part is that the sensation isn't necessarily proportional to the size of the insect.
A fire ant is only a few millimetres long.
You can barely see some of them.
Then one bites or stings you and suddenly you're wondering how something approximately the size of a breadcrumb has managed to ruin your afternoon.
And that's before you realize there are another hundred of them climbing up your leg.
The real problem is the colony
The biggest mistake people make around fire ants is thinking about them individually.
One ant isn't particularly impressive.
A colony is a completely different story.
Fire ants are social insects. They live in colonies containing workers, reproductive individuals and brood, and their colonies can contain enormous numbers of ants. Some imported fire ant colonies can reach hundreds of thousands of workers.
That means stepping on one isn't really an encounter with one ant.
It can be an announcement to an entire neighbourhood.
When a fire ant nest is disturbed, workers can emerge rapidly and attack whatever they perceive as a threat. The ants can swarm onto feet and legs, and because individual ants can sting repeatedly, the result can be much more unpleasant than a single insect sting.
This is why the safest approach is incredibly simple:
Don't stand on the nest.
What does a fire ant nest look like?
This is where things get interesting because not every fire ant colony gives you the obvious giant mound you might expect.
Some fire ants construct visible mounds in open ground, particularly in sunny areas such as lawns, fields, pastures and disturbed land. Other colonies can be much less obvious. The shape and visibility of nests can vary considerably.
And in tropical Panama, that matters.
A visitor may see a patch of apparently harmless grass beside a trail and think:
"Perfect place to stand while I take this photograph."
The ants may have a completely different opinion.
This is particularly worth remembering when sitting on the ground.
The jungle floor may look like an inviting natural picnic area, but it is also a functioning ecosystem containing thousands of creatures that consider that patch of soil their home.
Why fire ants are so successful
Fire ants are fascinating from a biological perspective.
They are extremely adaptable generalist foragers. They can eat a wide variety of food, including insects, other small animals, dead material and plant derived food sources. Their ability to exploit many different food sources is one reason fire ants have been so successful in places where they have established themselves.
They are also remarkably organized.
A fire ant colony isn't just a giant crowd of insects running around randomly.
Workers have different roles.
Some look after the brood.
Others forage.
Others defend the colony.
The queen or queens are responsible for reproduction.
The entire system operates as a highly coordinated superorganism.
And when you accidentally step on the nest, you have basically kicked the front door of that superorganism.
It is unlikely to react politely.
Fire ants aren't hunting tourists
This is an important distinction.
Fire ants aren't wandering around Panama looking for humans to attack.
They aren't predators of backpackers.
They don't sit beside jungle trails waiting for the next tourist.
Most of the time, they are simply going about their business.
The problem occurs when humans interfere with them.
Stepping on the nest is an obvious example.
So is putting your hand on a colony while climbing over a log.
So is sitting directly on a nest.
So is moving a piece of wood that happens to be their home.
In other words, most fire ant encounters are accidental.
You didn't go looking for them.
They didn't go looking for you.
Your feet simply ended up in the wrong place.
Panama's tropical environment is perfect for ants
One of the reasons Panama has such an incredible variety of ants is the country's combination of tropical climate, forests, wetlands, agricultural land and disturbed environments.
Panama is one of the great biological crossroads of the Americas.
You have North and South American species meeting here, enormous tropical forests, two oceans and a huge variety of habitats.
And ants are everywhere.
Scientists have documented hundreds of ant species in Panama, including species that are extremely specialized in their relationships with plants, fungi, insects and other organisms.
So when you're walking through Panama and notice a line of ants marching across a trail, you're looking at a tiny piece of a much larger ecological system.
Some are predators.
Some farm fungi.
Some protect plants in exchange for food.
Some steal food from other colonies.
Some live in trees.
Some live underground.
And some have developed an extremely effective way of convincing large mammals to leave them alone.
They sting.
Fire ants versus leaf cutter ants
Visitors sometimes confuse different types of ants because Panama is famous for its spectacular leaf cutter ants.
Leaf cutter ants are the ones you see carrying pieces of leaves along jungle trails in impressive organized highways.
They are fascinating.
But they are not fire ants.
Leaf cutter ants generally don't pose the same kind of stinging threat to people, although they can bite defensively.
Fire ants are much smaller and are often associated with disturbed or open ground rather than the spectacular leaf carrying trails that tourists photograph.
So if you see a line of ants carrying a piece of leaf twenty times their body weight, don't immediately assume you've found the infamous fire ant army.
You have probably found one of Panama's leaf cutter species doing what leaf cutters do best.
Why children and pets need extra attention
Fire ants can be particularly unpleasant for small animals.
Imported fire ants are known to sting people, pets and livestock, and young animals can be especially vulnerable.
That makes fire ant awareness particularly important around gardens, lawns, outdoor eating areas and places where animals spend time.
A dog sniffing around the ground doesn't necessarily understand that the little pile of insects underneath its nose is something it should leave alone.
Neither does a curious puppy.
And unlike a human, a dog may put its nose directly into the middle of a colony.
The lesson is simple.
If you're travelling with an animal in tropical Panama, pay attention to where it is putting its nose and paws.
What happens if you get stung?
For most healthy people, a fire ant sting produces a localized painful reaction.
You may experience burning, redness, itching and swelling. With some fire ants, the sting can later develop into a small pustule.
The important thing is to get away from the colony first.
This sounds obvious.
It isn't always obvious when several ants are already crawling on you.
If you've stepped into a nest, move away from the area and brush the ants off. Don't stand there trying to photograph the ants while they continue climbing up your legs.
If you develop signs of a severe allergic reaction, such as difficulty breathing, swelling of the face or throat, dizziness or widespread hives, seek emergency medical attention immediately.
Severe allergic reactions to insect stings can be medical emergencies.
The best way to avoid fire ants
The good news is that avoiding fire ants in Panama is usually very easy.
Don't sit directly on bare ground unless you've checked the area.
Don't stand on obvious ant mounds.
Watch where you're putting your feet.
Be particularly careful around sunny grassy areas and disturbed ground.
Don't stick your hands underneath logs or rocks without looking.
And if you see a huge number of ants moving in and out of one particular location, don't investigate by putting your hand in the middle of them.
You would think this would be common sense.
And yet, humans have an extraordinary ability to see something covered in insects and think:
"I wonder what happens if I touch it?"
Don't.
The fascinating thing about fire ants
Perhaps the most interesting thing about fire ants isn't actually their sting.
It's their organization.
An individual fire ant is tiny and relatively insignificant.
A colony is an entirely different creature.
Thousands of individuals cooperate to find food, raise young, defend territory and keep the colony functioning. The ability of these insects to work collectively is one of the reasons ants are among the most successful groups of animals on Earth.
And Panama is an extraordinary place to observe that world.
Look closely at the ground and you start to realize that the rainforest isn't simply filled with jaguars, monkeys and colourful birds.
It is absolutely packed with tiny lives.
Ants are moving.
Termites are building.
Beetles are hunting.
Spiders are waiting.
Fungi are growing.
Leaves are decomposing.
And everything is interacting with everything else.
The jungle is busy even when it looks completely still.
The tiny creature that earns respect
Fire ants are a perfect example of why travelling through Panama is so interesting.
You can spend the morning looking for a toucan, spend the afternoon watching monkeys and then spend the evening searching for frogs and insects with a flashlight.
But sometimes the wildlife encounter you remember most is something you didn't even notice until it was already climbing up your leg.
Fire ants aren't something to be terrified of.
They're something to respect.
Give their nests space and they will almost certainly ignore you.
Step directly into their living room, however, and you may discover that Panama's wildlife doesn't always need to be large, furry or covered in teeth to defend itself.
Sometimes the most memorable creature in the jungle is only four millimetres long.
And sometimes the smartest thing a traveller can do in Panama is simply look down before sitting down.