Why Do Bugs Have Antennae? – Explained In Simple Terms

Insects use antennae to sense both smell and touch and sometimes more. Antennae, sometimes known as simply ‘feelers’, are an important part of the biology of most insects.

This pair of long sensory organs are fitted with sensors and smell receptors to help give the insect an idea of the world around it.

The wonderful world of bugs is full of mysteries. Those things on top of an insect’s head might look weird – but they aren’t that different from our nose or tongue, and in some cases, they might even be more powerful!

In this brief article, we’re going to answer all your questions and touch on a few more feeler-facts:

  • How antennae work similarly to our own senses
  • Other kinds of animals that also have antennae
  • The different shapes and sizes of antennae found in nature
  • Ways that feelers help insects to socialize
  • Bugs that don’t have antennae at all

How Do Antennae Work?

When you look at your nose or a finger, it’s not too hard to figure out how they work. Antennae can be a little more confusing to understand.

Looking closer at antennae, what is happening cellular is somewhat similar to your nose – if it was inside out! The cells on the tip of the antennae take in odor receptors and transfer the information to the brain.

One thing insects can do that we can’t is to use both their flexible antennae to smell in many directions at once. This can be super handy when you’re out on the hunt for food or looking for a mate.

Antennae do more than smell too! Tiny microscopic hairs called sensilla are found all over the antennae. Certain kinds of these hairs instinctively jump at the slightest sign of pressure, or when the insect changes direction in midair.

These multiple examples of sensory feedback provide the insect with an idea of what is going on around it. As an insect’s eyesight is not traditionally known for being very good, this is important if it’s going to survive.

Feelers are also key when it comes time for mating. Insects rely on pheromones for attraction, you could say they flirt with their nose, so when it comes to breeding – antennae are crucial for the continuation of their species.

The different functions of the antennae are as diverse as the creatures that have them. Insects can do all kinds of things using these furry appendages.

These receptors can gather a wealth of different information in fascinating ways. It’s no wonder we name some of our technology after them!

Are Bugs the Only Kind of Animals with Antennae?

No – and they weren’t the first either! Arthropods are associated with antennae, A subsection of the animal kingdom that includes most insects and crustaceans. Think crabs, mites, and all kinds of bugs!

Not all of these guys have antennae, but many do, and they come in all shapes and sizes and represent about 80% of all species found on Earth today.

500 million years ago, in the Cambrian period, you may have seen a creature swimming around called a Kylinxia zhangi.

This underwater dweller looked like a cross between a millipede and a lobster, and it also had antennae. It is one of the common ancestors for both the critters hiding in your garage and the ones on your plate!

These days, sea crustaceans have antennae, but they look a little different from the stalks seen on a cockroach’s head.

Lobsters, crabs and shrimp have at least two separate sets, one short and one long. They come and go at different periods of the animal’s life, and can even be used for swimming and digging.

Do Antennae Come in Different Forms?

Evolution is weird! Antennae can appear vastly different from each other, and these differences have strange uses.

A range of different forms of antennae have appeared through natural history, and others have died out – some even to appear again out of nowhere.

Here are a few examples of some weird and wonderful feelers and how they look!

  1. Geniculate Antennae:

These feelers are hinged like an elbow joint, and are perhaps the most recognizable kind. You’ll know these antennae from ants and weevils.

team of ants gathering wild strawberry, agriculture teamwork
  1. Flabellate Antennae:

This form of antennae is a unique shape. These flowery-looking feelers extend out like a fan, and you might recognize them from wasps or specific kinds of beetles.

  1. Plumose Antennae:

These feathery antennae are very remarkable. They look like feathers and appear on mosquitoes and certain varieties of moths.

Do Insects Communicate with Antennae?

They may not look like it, but bugs are incredibly social creatures. We only have to look at ants to see what complex societies these critters can create.

Insects speak to each other, not with words but with chemicals, smells and signals. Antennae are essential for insect communication!

In 1886, a scientist named Auguste Forel conducted a very fascinating, and very cruel, experiment to prove the importance of antennae when it comes to bug identity.

After removing the antennae, he dropped a variety of ants in a single container. The ants lost their usual order, proving that these insects use their feelers to recognize each other.

Other insects use these feelers to show their gender. In many species, biologists have noticed that insects may have different antennae sizes.

The bigger is often associated with male, and the more slender or smaller with female. This can even make a difference when it comes to choosing a mate.

Do All Bugs have Antennae?

You might have a hard time trying to name one kind of insect that doesn’t have antennae. However, there is an entire sub-section of insects that don’t. Scientists know them as Arachnida.

While the word may bring freaky eight-legged creatures to mind, this variety of critter is more diverse than it sounds.

  1. Spiders:

These insects may be at the top of most people’s list of the greatest fears. There’s a lot to fear! Spiders have eight eyes and eight legs – but no antennae in sight.

These creatures don’t need them to feel or smell, they can do that with their own feet.

Super Macro Jumping Spider Hyllus in Tropical Park
  1. Scorpions:

Adding to the list of fearsome arachnids are Scorpions. These stinging insects actually look closest in appearance to other undersea crustaceans but are removed by a few key features – one of which is a lack of an antennae!

  1. Mites:

Next on the list is an insect that you might struggle to see at all! Most are less than 1mm in size and are hard to catch in the naked eye.

With this tiny size, these insects are small enough to have smell receptors on their bodies without need of extremities.

  1. Ticks:

These parasites are something you might want to avoid seeing! These bloodsuckers can smell, but only the carbon dioxide that comes off your skin – and also ranging at very small sizes, they don’t need an antenna for that.

Conclusion

There are so many weird things about nature, and it certainly produces some funny stuff. Like all aspects of every creature on earth, antennae are more than just fancy-looking, they play a crucial role for every insect that has them.

They help these bugs to mate, sense the world around them and even recognize each other

So remember, next time you see a crawly little friend out in nature somewhere. Just remember, those funny little feelers on top of their head may even help them notice you too!

Alright, that’s it for this article, here are a few hand-selected articles that you might also find interesting reads:

Why Do Spiders Have 8 Eyes? The Curious Answer

Why don’t insects die when they fall – The Curious Answer

Why Do Bugs Just Sit There For Hours!? Here’s Why

Steve Foster

Mad about bugs and wanting to publish as many articles as I can to help educate people about these amazing beautiful creatures! For more info check out my about page https://schoolofbugs.com/about-steve-foster/

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