Have you ever wondered why some animals completely change their bodies during their lives? While humans might grow taller or change our hairstyles, we generally keep the same body. But for about 80% of animal species, this isn’t the case. They go through a process called metamorphosis, which helps them tackle different challenges at various stages of their lives.
Hi, I’m Kate from MinuteEarth. Let’s take a look at the mayfly. When a mayfly is born, its main job is to eat and grow. As a larva, it spends months munching away to get bigger. But when it’s time to reproduce, its body isn’t suited for finding a mate. So, it transforms into an adult mayfly, which is built for reproduction. Interestingly, adult mayflies don’t even have working digestive systems and live only for a day or two, just long enough to find a mate and pass on their genes.
Metamorphosis allows animals to focus on what’s most important at different life stages. For example, some young sea creatures float around in the ocean until they eventually settle on the seafloor and transform into adult starfish. This change from a mobile larva to a settled adult helps them adapt to their environment and reproduce.
Switching body types also means that young animals and adults don’t compete for the same food. This way, they can each find their own food sources. Instead of wondering why so many animals change their bodies, we might ask why more animals don’t do it.
Metamorphosis isn’t easy. It takes a lot of energy, and there are risks involved when an animal sheds its old body to grow a new one. This is why most animals that undergo metamorphosis only do it once in their lives. Some animals, like those that care for their young, don’t need to change bodies because they can help their offspring thrive in a single form. Others, like humans, have larger brains that help us solve problems as we grow, so we don’t need to change bodies.
Creating different body types from the same genetic material is a complex process. It involves turning certain genes on and off at the right times. This ability has evolved only a few times in the history of life on Earth, and one of these instances accounts for most of the animals that can change their shape.
Humans are among the few species that don’t undergo metamorphosis. Our larger brains and nurturing parenting style mean we don’t need to. While it might be cool to suddenly grow wings, it’s nice to know we don’t have to go through such drastic changes.
This article is brought to you by Mondly, a language learning app offering a big discount on lifetime access during their back-to-school sale. Mondly helps you learn any of 41 languages with daily lessons and quizzes. It focuses on practical skills you can use in everyday life, like writing emails in Spanish. Over 100 million people use Mondly because of its practical approach. To start learning today, visit mondly.app/minuteearth or click the link in the description. Thanks, Mondly!
Imagine you are a caterpillar preparing to transform into a butterfly. Write a short diary entry describing your thoughts and feelings about the upcoming change. Consider what challenges you might face and what you are looking forward to as a butterfly.
Create a comic strip that illustrates the life cycle of an animal that undergoes metamorphosis, such as a butterfly or a frog. Use drawings and captions to show each stage of the cycle and highlight the main changes that occur.
Participate in a class debate about the advantages and disadvantages of metamorphosis. Divide into two groups, with one group arguing for the benefits of metamorphosis and the other discussing its challenges. Use examples from the article to support your arguments.
Research how genes are turned on and off during metamorphosis. Create a simple simulation using colored paper or digital tools to represent different genes. Show how activating or deactivating these genes leads to changes in the animal’s body.
Design an art project that represents the concept of metamorphosis. Use materials like clay, paper, or digital media to create a before-and-after depiction of an animal that undergoes metamorphosis. Display your artwork in the classroom and explain the transformation process to your classmates.
Here’s a sanitized version of the transcript:
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Throughout our lives, humans may change in appearance or develop new features, but we essentially maintain the same body. This seems normal. However, most animal species—around 80 percent—actually replace their body parts or even their entire bodies at some point in their lives. This process, known as metamorphosis, may seem complex, but it addresses a common challenge faced by many animals.
Hello, I’m Kate, and this is MinuteEarth. When a mayfly is born, its main focus is to eat and grow as much as possible. The mayfly larva is essentially an eating machine, spending months consuming enough food to increase its size significantly. Eventually, its focus shifts to reproduction, and its current body is not suited for finding a mate. So, it undergoes a transformation into a new form that is better equipped for this purpose. Adult mayflies, which lack functional digestive systems, have one goal: to find a mate and pass on their genes before they die within a day or two.
In essence, metamorphosis allows animals to specialize in what is most important at different life stages. For example, this young creature floats in the ocean, riding currents before eventually sinking to the seafloor and transforming into a more recognizable adult starfish. This pattern of metamorphosis—from a mobile larva designed for dispersal to a less-mobile adult focused on settling down and reproducing—occurs in most ocean-dwelling invertebrates.
Switching body types not only helps animals achieve different goals throughout their lives but also allows them to find and consume different types of food. This means that in species that undergo metamorphosis, juveniles do not have to compete with adults for resources. Instead of questioning why so many animals undergo these significant changes, we might consider why even more animals do not.
Some of this may relate to the disadvantages of metamorphosis. Changing body types requires a significant amount of energy, and as an animal sheds its old body and acquires a new one, various challenges can arise. These risks and costs may explain why most animals that undergo metamorphosis do so only once. Other species manage without changing bodies at all; for instance, animals that care for their young can help their offspring thrive in a single body type, and those with larger brains can adapt and solve problems effectively throughout different life stages.
Additionally, the biological complexity of this process is noteworthy; creating different body types from a single genome involves a complex sequence of gene activation and deactivation. This system appears to have evolved only a few times, with one instance likely accounting for the majority of shape-shifting animals.
Humans are part of the minority of species that have not evolved the ability to completely change our bodies and likely never will, due to our larger brains and nurturing parenting style. While it might be fascinating to suddenly develop wings, I appreciate that we do not need to.
This video is sponsored by Mondly, which is offering a significant discount on lifetime access during their back-to-school sale at mondly.app/minuteearth. Mondly is a language learning app that allows you to learn any of 41 different languages through daily lessons and quizzes. It focuses on practical lessons that can be applied in everyday life. For example, if you are improving a second language, you can choose modules that target specific tasks, such as writing better emails in Spanish. This practical approach is likely why over 100 million people use it. To get started today and take advantage of the back-to-school sale, visit mondly.app/minuteearth or click the link in the description. Thank you, Mondly.
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This version maintains the core content while removing any informal language or unnecessary details.
Metamorphosis – A biological process in which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal’s body structure. – Example sentence: The butterfly undergoes metamorphosis, transforming from a caterpillar into a beautiful adult butterfly.
Mayfly – A type of aquatic insect that is known for its short adult life span and is often used as an indicator of water quality. – Example sentence: The presence of mayflies in the river indicates that the water is clean and healthy.
Larva – An early stage in the life cycle of an organism, typically differing greatly in form and function from the adult stage. – Example sentence: The larva of a frog, known as a tadpole, lives in water and breathes through gills.
Reproduce – The biological process by which new individual organisms are produced from their parents. – Example sentence: Plants reproduce by spreading seeds that grow into new plants.
Environment – The surrounding conditions, including living and non-living factors, that affect the life and development of organisms. – Example sentence: The rainforest environment is home to a diverse range of plant and animal species.
Adapt – The process by which a species becomes better suited to its environment through changes in its characteristics. – Example sentence: Polar bears have adapted to their cold environment by developing thick fur and a layer of fat.
Energy – The ability to do work or cause change, which organisms obtain from food or sunlight to carry out life processes. – Example sentence: Plants use sunlight to produce energy through the process of photosynthesis.
Genes – Units of heredity that are made up of DNA and determine the characteristics of an organism. – Example sentence: Genes inherited from parents determine the traits of an offspring, such as eye color and height.
Species – A group of organisms that can interbreed and produce fertile offspring, sharing common characteristics. – Example sentence: The giant panda is a species that is native to the mountain ranges of central China.
Challenges – Obstacles or difficulties that organisms face in their environment, which can affect their survival and reproduction. – Example sentence: Climate change presents significant challenges to many species, forcing them to adapt or face extinction.
