When you leave food remnants in a sealed container outside the refrigerator for a week or more, and then return to open it
regardless of the unpleasant odor you will notice the presence of insects inside the closed container.
The same phenomenon occurs with a piece of fruit, such as an apple. If left outside for a few days, cutting it open may reveal worms inside.
So, how do insects and worms suddenly appear inside the fruit or food containers? And what is their source?
Aristotle's Spontaneous Generation Hypothesis
The appearance of worms and insects inside food has intrigued people for hundreds of years, leading to the emergence of a hypothesis known as "Spontaneous Generation."
This hypothesis was first introduced by the Greek philosopher Aristotle and remained widely accepted until the 18th century.
It proposed that living organisms could arise spontaneously from non-living matter under specific conditions.
For instance, it was believed that dust or dirt could generate fleas, and that meat or proteins could produce worms.
These ideas were based on simple observation and empirical evidence.
One such observation involved placing a piece of meat in a sealed container and leaving it for some time.
Upon reopening the container, worms were found inside the meat, leading to the conclusion that the meat itself had generated the worms.
Surprisingly, Aristotle's claims were not limited to microscopic organisms; he even attempted to apply the Spontaneous Generation hypothesis to larger living creatures.
He believed that seashells at the bottom of the ocean spontaneously formed from seabed sand.
Others expanded on this idea, suggesting that crocodiles and snakes emerged from Nile River silt and that mice were generated from a mixture of dirty cloth and wheat a belief rooted in the observation that mice were often found inside grain sacks in ancient times.
However, the Spontaneous Generation hypothesis is entirely incorrect, filled with myths, and has no scientific basis.
The principle of biological reproduction
As we know, living organisms must reproduce from other living beings, a concept known as "Biogenesis." Worms, like all other organisms, follow this principle.
The worms that appear on decaying food do not emerge from nothing; instead, they originate from another living creature flies.
How do worms appear inside fruit?
If you find larvae or worms on food, you can be certain that insects or flies have previously landed on it, laid their eggs, and then flown away.
This behavior is very common in the insect world, especially when it comes to protein-rich foods, as they serve as a valuable food source for them.
The same applies to fruits and vegetables if you cut open a fruit or vegetable and discover worms inside, it means that an insect had previously laid its eggs on it.
Fruits and vegetables attract insects and flies because they are drawn to the sucrose found in most of these foods.
Flies land on the surface of the fruit, attempting to create a small hole to lay their eggs inside.
Over time, these eggs hatch and develop into the worms we see. The first person to discover this process was the Italian physician and scientist Francesco Redi.
In 1668, he conducted a series of scientific experiments to determine whether worms truly appeared out of nowhere, as was commonly believed at the time.
The experiment consisted of three jars, each containing a piece of raw meat:
- The first jar was exposed to the air.
- The second jar was covered with a soft cloth to allow air to enter the jar and keep out insects.
- The third jar was covered with a lid to keep the air out completely.
He then observed the jars for several days, and his first key observations were as follows:
- First jar: A large number of insects and flies entered the jar.
- Second jar: Flies gathered around it and landed on the fine cloth for some time, attempting to get inside.
- Third jar: No flies approached it.
Upon observing the jars, Francesco Redi noted the following results:
- First jar: Worms appeared inside, feeding on the piece of meat.
- Second jar: Dead worms were found on the outer surface of the fine cloth.
- Third jar: No worms appeared inside or outside the jar.
From these observations, Francesco Redi concluded that the worms were actually the larvae of flies that had laid their eggs near the food.
This explained why no worms appeared in the sealed jar flies couldn't access it to lay eggs.
However, his experiments didn’t stop there. To confirm his findings, Redi took the open jar where worms had appeared and sealed it tightly, then observed it for several days.
At first, he noticed that the worms began forming brown cocoons around themselves (a transitional stage after the larval phase).
After a few days, the cocoons opened, and small flies emerged, moving around inside the jar.
This experiment proved that whenever worms are found on food, it means that a fly or insect previously landed on it and laid eggs.
Therefore, in the case of tightly sealed containers, such as canned tuna or mushrooms that remain unopened since production, it is impossible for worms to appear inside.
The difference between fungi and worms in food
However, some might disagree with the previous conclusions, as people sometimes purchase canned products and, upon opening them, find mold inside.
But let me clarify there is a significant difference between a container with fungi and one containing worms; these are two entirely different cases.
Everything organic around us that is exposed to air contains various bacteria and fungi, whether beneficial or harmful.
Since these microorganisms are microscopic, we do not notice their presence.
In reality, all of our food whether vegetables, fruits, meat, or even wood and dust in the air contains a vast number of microorganisms when observed under a microscope. Many videos and studies illustrate this phenomenon.
However, the presence of these microscopic creatures is a blessing from our Creator, as they play a crucial role in maintaining ecological balance by breaking down and decomposing organic matter.
The fungi and bacteria naturally found in food are usually present in low quantities and do not affect human health or food quality.
However, over time, these fungi begin to multiply and spread across the surface of the food.
When the right conditions such as humidity or constant exposure to air are present, these microorganisms multiply even more.
This is why factories add preservatives to canned products to extend their shelf life.
However, preservatives do not prevent fungal growth indefinitely. They are added in small amounts and can only resist fungi for a limited period.
Over time, their effect diminishes, allowing fungi to grow inside sealed cans, even if the container remains tightly closed and was never exposed to air.
This highlights the key difference between a product that develops mold (fungi) and one that contains worms (larvae from flies and insects).
Worms cannot appear inside a sealed can unless a fly or insect had access to it at some point.