There’s a new and unusual organism on display at the Paris Zoo, and it’s not your typical zoo animal. It doesn’t have eyes, ears, a mouth, or limbs, but it can move, communicate, heal itself, and has nearly 720 different sexes. Introducing the slime mold, affectionately known by scientists as “le blob.”
Despite its name, a slime mold isn’t a fungus. It’s actually a type of protist, which belongs to a group called Amoebozoa. There are two main types of slime molds: cellular and acellular. Cellular slime molds are tiny amoebas that you need a microscope to see. They can come together to form a larger blob that acts like a single organism, which is why they’re sometimes called social amoebas.
The slime mold at the Paris Zoo is an acellular type called Physarum polycephalum. It starts as a single amoeba, but as it grows, its nuclei multiply without the cell dividing. This creates a giant cell called a plasmodium, which looks like a big yellow blob. This blob moves its insides around in vein-like patterns, teaching scientists a lot about how cells transport materials.
For a long time, scientists weren’t sure how to classify slime molds. Like fungi, they produce spores, which are tiny particles that can grow into new organisms. However, unlike fungi, slime molds eat by engulfing their food whole, rather than breaking it down outside their bodies. Plus, slime molds can move around, while fungi stay in one place.
Slime molds are also quite smart. Some studies show that cellular slime molds can act like farmers. They eat bacteria but save some to grow more in new places for their offspring. This shows a kind of planning and resource management.
Acellular slime molds like “le blob” can learn in a way. They can get used to ignoring harmless but annoying chemicals to reach their food, a process called habituation. They can remember this even after being inactive for a long time and can share this knowledge with other slime molds. If two slime molds merge, and one has learned to ignore a chemical, the new combined organism will also ignore it.
Scientists are still trying to figure out how slime molds do this. The way they learn and remember isn’t fully understood, and there’s debate about whether it should be called cognition, which is a term usually used for brains.
One of the most interesting facts about slime molds is that they can have almost 720 sexes. There aren’t just male and female categories. Instead, there are hundreds of possible combinations. Each spore, which is a single sex cell, has half the genetic information needed to form a new slime mold. When two spores meet, they combine in many different ways, creating a wide variety of sexes.
What’s the coolest thing about slime molds to you? Would you like to learn more about these amazing organisms? Let us know your thoughts, and don’t forget to subscribe for more surprising facts. For more on the wonders of the microbial world, check out our video on fungal networks. Thanks for reading, and see you next time!
Use clay or playdough to create a model of a slime mold. Focus on showing the plasmodium structure and how it moves. This hands-on activity will help you visualize the unique characteristics of slime molds.
Design a simple maze on paper and use a small amount of slime mold (if available) or watch a video of this experiment. Observe how the slime mold finds the shortest path to food, demonstrating its problem-solving abilities.
Choose one aspect of slime molds, such as their learning abilities or reproductive methods, and research it further. Create a short presentation to share your findings with the class, enhancing your understanding and communication skills.
Draw or paint an artistic representation of a slime mold, focusing on its vibrant colors and vein-like patterns. This activity encourages creativity while reinforcing the visual aspects of slime molds.
Create a quiz for your classmates about slime molds, including questions on their characteristics, behaviors, and unique features. This will help you and your peers review and reinforce the information learned.
Here’s a sanitized version of the YouTube transcript:
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There’s a brand new organism on display at Le Parc Zoologique de Paris, one that might win the title of strangest thing in a zoo ever. Because it’s not an animal. It has no eyes, ears, mouth, or limbs, but it is mobile, can communicate, can heal itself, and has nearly 720 biological sexes. It’s *drumroll please*…a slime mold. Affectionately called by some scientists who study it: “le blob.”
So what exactly is a slime mold? While its name may lead you toward the fungal section of the tree of life, slime molds are actually protists, belonging to the phylum Amoebozoa. There are two very different kinds of slime molds: cellular and acellular. Cellular slime molds are tiny amoebas that require a microscope to see, but they can clump together into a slimy blob that acts as one whole superorganism. That’s why this kind of slime mold is sometimes called the social amoeba—they like to gather together under the right conditions.
The one we’re talking about, now in the Paris Zoo, is an acellular slime mold whose official name is Physarum polycephalum. This organism starts as an amoeba, but as it continues to grow, the nuclei divide, while the cell does not. It essentially forms into one giant cell, called a plasmodium. This large yellow moving structure is just one cell, like a giant bag full of many nuclei. It moves its cytoplasm around in vein-like structures, which is teaching us quite a lot about cellular transport.
Scientists were confused about how to classify slime molds for a long time. Like fungi, they have spores. They start out as microscopic spores before developing into the slime mold we can see, and when they reach a certain stage in their life cycle and their environment becomes unfavorable, they disintegrate back into spores. Unlike fungi, when slime molds eat, they swallow food whole instead of releasing enzymes to break it down outside their bodies. Another key difference is that slime molds are highly mobile, while fungi are more stationary.
Their adventurous nature is not all that makes them special. Slime molds exhibit intelligent behavior. Studies have shown that social amoeba—those cellular slime molds—demonstrate agricultural behavior. They eat bacteria but sometimes save some for later, carrying it with them to grow more in new locations for their offspring. Slime molds are farmers!
Research has shown that acellular slime molds like “le blob” can demonstrate something akin to learning. P. polycephalum slime molds can learn to ignore uncomfortable but harmless chemicals to access their food source, a process known as habituation. These organisms can retain that information during long periods of dormancy and can pass on this knowledge to other slime molds that have never encountered that chemical before. If separate slime molds are cut and then introduced to each other, they can form into one whole mass. If just one piece is from a slime mold that was habituated to the unpleasant chemical, the entire re-formed organism also recognizes that the chemical isn’t harmful.
We still don’t fully understand how this works. The mechanisms behind this cognition are not well defined, and many researchers, particularly in neuroscience, debate whether it should even be called cognition. There’s still much to explore.
As an interesting fact, “le blob” can have almost 720 sexes. There are no male or female categories, just hundreds of different possible sex categories. The spores are haploid, meaning each contains only half of the necessary genetic information to form a whole slime mold. Each haploid sex cell carries one copy of three different possible sex genes, each with various forms. When a haploid sex cell finds its counterpart, the combinations result in many hundreds of possible options for the sex of the resulting organism.
What’s the coolest part about slime molds to you? Would you like us to cover more aspects of these organisms in detail? Let us know in the comments, and make sure to subscribe for more surprising facts. For more microbial magic, check out this video on fungal networks, and as always, thanks for watching. See you next time!
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This version maintains the informative content while ensuring clarity and appropriateness.
Slime – A slippery substance produced by certain organisms, often used for movement or protection. – The snail left a trail of slime as it moved across the leaf.
Mold – A type of fungus that grows in the form of multicellular filaments called hyphae. – The bread was left out too long and started to grow mold.
Protist – A diverse group of mostly single-celled organisms that are not plants, animals, or fungi. – The pond water was teeming with protists, visible under the microscope.
Amoebozoa – A group of protists characterized by their amoeba-like movement using pseudopodia. – Amoebozoa move by extending their cell membrane to form pseudopods.
Plasmodium – A genus of parasitic protists, some of which cause malaria in humans. – The Plasmodium parasite is transmitted to humans through mosquito bites.
Spores – Reproductive cells capable of developing into a new individual without fusion with another cell. – Fungi release spores into the air to reproduce and spread.
Bacteria – Microscopic single-celled organisms that can be found in various environments. – Bacteria play a crucial role in decomposing organic matter in the soil.
Cognition – The mental process of acquiring knowledge and understanding through thought and experience. – Scientists study animal cognition to understand how different species learn and solve problems.
Memory – The ability of an organism to store, retain, and recall information. – Bees use memory to remember the location of flowers with nectar.
Habitat – The natural environment where an organism lives and thrives. – The rainforest provides a rich habitat for a diverse range of species.
