insects

WTF Fun Fact 13588 – Ants Don’t Have Lungs

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Did you know that ants don’t have lungs?

One may wonder how they fuel their high energy and rapid movement. The answer lies, in part, in their unique respiratory system. Unlike larger animals, ants don’t have lungs. Instead, they rely on a network of tiny tubes to breathe. This intricate system is not only fascinating but is also a testament to nature’s adaptability.

Ants Don’t Have Lungs, So How Do They Breathe?

Ants, like other insects, use a system of tubes called tracheae to transport oxygen to their tissues and remove carbon dioxide. These tracheae branch out into finer tubes, spreading throughout the ant’s body and reaching every cell. The tracheae system is like a highly efficient highway network that delivers oxygen straight to where it’s needed.

At the surface, openings called spiracles allow the entry and exit of gases. These spiracles can be found on the ant’s thorax and abdomen. They operate like valves, opening to allow oxygen in and carbon dioxide out, and closing to prevent water loss. This mechanism ensures that ants can regulate their oxygen intake and carbon dioxide release, maintaining an optimal internal environment.

One might wonder how oxygen enters and carbon dioxide exits the tracheae without the pumping mechanism we associate with lungs. The secret here is diffusion. Due to the small size of ants, the distance between the spiracles and the internal cells is minuscule. This allows gases to naturally diffuse in and out based on concentration gradients.

When the oxygen level outside an ant is higher than inside, oxygen molecules move into the tracheae through the spiracles. Conversely, when the carbon dioxide level inside the ant is higher than outside, the gas moves out of the tracheae, again through the spiracles. This passive process eliminates the need for a more complex respiratory organ like lungs.

The tracheal system presents several advantages for ants. First, it’s lightweight. Lungs, with their associated tissues, can be relatively heavy, especially when filled with blood and other fluids. Ants, needing to be agile and quick, benefit from not having this extra weight.

Moreover, the tracheal system provides direct oxygen delivery. In larger animals, oxygen absorbed by the lungs needs to be transported by the circulatory system to reach individual cells. But in ants, the tracheal tubes deliver oxygen straight to the cells, ensuring immediate supply and reducing any delay in oxygen transport.

Ants’ Adaptations for High Activity Levels

Considering the bustling nature of ant colonies and their constant search for food and resources, one might wonder how their simple respiratory system keeps up. Ants have evolved behaviors and physical adaptations to ensure they maintain a constant supply of oxygen.

For instance, ants often move in a coordinated manner, ensuring that they don’t overcrowd a particular area, which could potentially limit the available oxygen. Additionally, their exoskeletons are thin, which further facilitates the efficient diffusion of gases.

Furthermore, some ant species have evolved specialized structures in their tracheal system that allow for more efficient gas exchange, especially when they’re deep within their nests. These adaptations ensure that even in crowded, subterranean environments, ants receive the oxygen they need.

The ant’s respiratory system might be efficient for their size, but this system wouldn’t work for larger organisms. As body size increases, the distance between the external environment and internal cells becomes too great for diffusion alone to be effective. That’s why larger animals, including humans, have evolved complex respiratory systems like lungs, and intricate circulatory systems to transport oxygen to individual cells.

In essence, while the ant’s method of breathing is impressively efficient for its tiny form, nature has found diverse solutions for different species based on their size, habitat, and activity levels. It’s a testament to the adaptability and innovation of evolution.

—WTF fun facts

Source: “How do ants breathe?” — BBC Science Focus

WTF Fun Fact 13585 – Butterflies Taste With Their Feet

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Did you know that butterflies taste with their feet?

A Different Sensory World

Humans rely heavily on their eyes, ears, and mouth to interact with the world. We use our tongues to savor different flavors, but butterflies operate on a completely different sensory level. Their feet, not their mouths, are the primary tools for tasting. Before they even consider taking a sip of nectar from a flower or laying an egg on a plant, they first “taste” the surface to ensure it’s the right spot.

Why is this so? For a butterfly, survival depends on precise choices. Laying eggs on the wrong plant can spell disaster for the caterpillars that hatch, as they might not have the right food to eat. By using their feet to taste, butterflies can instantly determine if a plant is suitable for their offspring.

The Science Behind Foot-Tasting and How Butterflies Taste With Their Feet

Butterflies have specialized sensory organs called chemoreceptors on their feet. These chemoreceptors can detect and analyze minute chemical compositions on surfaces. When a butterfly lands on a plant, these sensors quickly determine the plant’s chemical makeup. If it matches the dietary needs of their caterpillar offspring, the butterfly knows it’s found the right place to lay its eggs.

Additionally, these chemoreceptors help butterflies locate nectar. Just by landing on a flower, they can sense if it’s worth their time or if they should move on to another bloom. Their feet essentially function as both a survival tool and a guide to the best dining spots.

How Do Chemoreceptors Work?

Just like our taste buds can identify sweet, salty, sour, and bitter, butterfly chemoreceptors detect various chemical compounds. When these compounds come into contact with a butterfly’s feet, a reaction occurs that sends signals to the insect’s brain. This rapid transmission of information allows the butterfly to make almost instantaneous decisions. It’s a quick and efficient system that ensures the butterfly spends its short life making the best choices for feeding and reproduction.

This unique tasting method has influenced various aspects of butterfly behavior and anatomy. For one, butterflies are exceptionally picky about where they land. They are often seen flitting from one plant to another, not just for the joy of flight, but in a quest to find the perfect spot that matches their tasting criteria.

Furthermore, their legs are perfectly designed for this purpose. Lightweight yet strong, they allow for quick landings and take-offs, and their structure ensures that the chemoreceptors come into maximum contact with surfaces, providing the most accurate readings.

Butterflies have short lifespans. Many species only live for a few weeks as adults. Given this limited timeframe, it’s essential for them to make the most of every moment. This is where their foot-tasting ability becomes crucial. It allows them to quickly discern the best places to lay eggs or feed, ensuring their genetic legacy and personal survival.

Moreover, the tasting mechanism influences their mating rituals. Male butterflies release specific chemicals to attract females. When a female lands near a potential mate, she can instantly “taste” these chemicals and decide whether the male is a suitable partner.

The Wider Impacts of Butterflies Tasting With Their Feet

This incredible adaptation doesn’t just affect butterflies; it impacts entire ecosystems. Plants have co-evolved with butterflies over millions of years. Some plants have developed chemicals specifically to attract butterflies, ensuring their pollen is spread. Others have developed deterrent chemicals to ward them off.

Such co-evolutionary dynamics shape our environment, leading to the diverse range of plants and butterfly species we see today. It’s a dance of chemistry and taste, all playing out under our very noses (or, in the case of butterflies, under their feet).

—WTF fun facts

Source: “How Do Butterflies Taste And Eat Their Food?” — Science ABC

WTF Fun Fact 13443 – Dead Fruit Flies

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When fruit flies see or smell their dead comrades, their own lives are cut short. Talk about putting a damper on your day!

Fruit flies stress after seeing other dead fruit flies

If you’re a fruit fly, seeing one of your fallen is not just unsettling. It’s downright harmful to your health. Despite their diminutive size, experience stress and negative health effects when they witness the remains of their kin.

Neuroscientists have found that when fruit flies (Drosophila melanogaster) see their deceased fellow flies, specific brain cells are triggered.

And these aren’t just any brain cells. They are neurons that respond to visual stimuli, known as visual projection neurons (VPNs). These cells relay information from the flies’ eyes to their brains, helping them interpret and react to what they see.

What’s going on in a fruit fly’s brain?

But let’s add a pinch of intrigue to the mix. These neuroscientists didn’t stop at merely identifying the type of neurons involved. They zeroed in on the specific group of neurons that reacts to the sight of dead flies. The neurons in question are part of a cluster known as the “globus pallidus.” This is an area associated with movement and learning.

These scientists have discovered the precise neighborhood in the fruit fly’s brain where the “dead fly sighting stress response” takes place.

So, what happens when these neurons fire? In short, they trigger a series of stress responses that have a tangible impact on the fruit flies’ health and lifespan. As the sight of a dead fellow fly becomes ingrained in the fly’s brain, it alters the expression of stress-related genes, tipping the physiological balance and leading to a shorter lifespan.

This discovery has raised intriguing questions about the evolution of empathy and social responses in insects. While fruit flies may not experience empathy in the way humans do, their stress response to seeing dead comrades suggests a level of social awareness. This raises the question: why would such a response evolve? One possibility is that the sight of death serves as a warning signal, indicating the presence of potential threats or diseases, thus prompting the fly to modify its behavior.

However, this remarkable finding does more than just throw light on fruit flies’ stress responses. It could also contribute to our understanding of how human brains process stress and trauma. Humans, like fruit flies, have neurons that respond to visual stimuli. Therefore, these findings could lead to a better understanding of how our brains respond to stressful visual experiences, and potentially inform treatments for stress-related disorders.

— WTF fun facts

Source: “Seeing dead fruit flies is bad for the health of fruit flies – and neuroscientists have identified the exact brain cells responsible” — The Conversation

WTF Fun Fact 13143 – Grass Screams When Cut

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You’ll never cut your grass again without thinking of this weird fact – grass cries for help when it’s mowed. No, you can’t hear it, but scientists have discovered grass screams when cut.

How does grass scream when cut?

We’re only just beginning to understand how plants communicate with one another and the rest of the world around them (including insects).

Dr. Michael Kolomiets, a Texas A&M AgriLife Research plant pathologist, published an article in 2014 in The Plant Journal noting that the aroma of cut grass is the plant’s way of both signaling distress and attracting beneficial insects that will help it heal.

According to ScienceDaily (cited below): “When there is need for protection, the plant signals the environment via the emission of volatile organic compounds, which are recognized as a feeding queue for parasitic wasps to come to the plant that is being eaten and lay eggs in the pest insect,” Kolomiets said.

Plant communication

Grass produces a “defensive” protein when damaged. Of course, that doesn’t stop the lawnmower or insects from destroying the blades. But it appears to produce a compound that repels insects that are feeding on the damaged grass.

This compound, or one related to it, also appears to attract organisms like parasitic wasps that feed on insects like caterpillars that are destroying the grass.

Or to put it in science-speak:

“We have proven that when you delete these volatiles, parasitic wasps are no longer attracted to that plant,even when an insect chews on the leaf. So this volatile is required to attract parasitoids. We have provided genetic evidence that green leafy volatiles have this dual function — in the plant they activate production of insecticidal compounds, but also they have indirect defense capability because they send an SOS-type signal that results in attraction of parasitic wasps.”

So, maybe it’s not so much that grass screams when cut so much as it cries for help. Either way, freshly cut grass emits a compound that repels damaging insects and attracts insects with a protective function.

It’s just one of the many ways that plants are far more complex than we had ever previously imagined. — WTF fun facts

Source: “Mown grass smell sends SOS for help in resisting insect attacks” — ScienceDaily

WTF Fun Fact 12725 – Ancient Stone Pillows

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It’s hard to find a good pillow. And while some of us like our pillow firm, it would take a major adjustment to sleep like ancient Mesopotamians and Egyptians (well, in more ways than one, I suppose).

Here’s one of the most famous pillows in history, brought to you from Egypt King Tut’s tomb:

One of 8 headrests found in Tutankhamun’s tomb. The god of air, Shu, is carved in ivory. The piece resides in the Egyptian Museum in Cairo.

It’s beautiful, but it lacks the kind of functionality we typically look for today.

Until the Industrial Revolution, pillows weren’t even a household object. Yes, some ancient Greeks and Romans did stuff straw in cloth to lay their heads on, but a pillow is also a symbol of having excess lying around to use for more practical purposes. However, we can credit the Greeks with bringing us closer to the era of the soft pillow.

However, in ancient Mesopotamia, China, and Egypt, wealthy people would elevate their heads on “pillow” made of stone (or ivory – or another luxury material). They were designed to keep insects out of their ears, noses, and mouths – and probably to maintain a good hairstyle every now and then.

We’ve also found some pillows that are beautifully engraved with messages about keeping away bad spirits as well, but it’s unclear how those would be fooled by an elevated head. Still, it gives us a good idea of what ancient people were concerned about when they laid down their heads at night. — WTF fun facts

Source: “HEADRESTS IN GLENCAIRN’S EGYPTIAN COLLECTION: PRACTICALITY AND PROTECTION” — Glencairn Museum