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You're listening to sleep Tight Science.

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Did you know that you can tell

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if a frog is a boy or a girl

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by the size of its ear drum. What

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if the ear drum is about the same

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size as the frog's eye, you're

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looking at a girl frog, but

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if it's noticeably larger than

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the eye, you've spotted a boy

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frog. Hello,

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friends, and welcome back to sleep

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Tight Science, a bedtime show

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that answers your questions about

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science. In

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this episode, we are going to

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jump into the fascinating and

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diverse world of frogs. We'll

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explore what makes amphibians

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so unique, delve into

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the incredible life cycle of frogs,

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and understand the various environments

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in which they thrive across the globe.

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We'll also uncover what these amazing

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creatures eat to fuel their leaps

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and hops. After

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that, we'll answer some listener

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questions and share some fun facts

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to satisfy your curiosity

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about frogs. So

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let's begin by discussing what amphibians

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are. Amphibians

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are a diverse group of vertebrates

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characterized by their unique life

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cycle and ability to live

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in water and on land. There

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are about seven thousand known

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species of amphibians, making

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them the smallest group of vertebrates, yet

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they play a crucial role in their ecosystems.

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Like fish and reptiles, amphibians

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are ecothermic or cold blooded,

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which means they do not generate their

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own body heat, but rely

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on external sources like the sun

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to regulate their temperature. Most

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amphibians begin their lives

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in water, where they hatch from eggs

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and breathe through gills similar

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to fish. As they grow,

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they undergo a remarkable transformation

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known as metamorphosis, during

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which they develop lungs and legs

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that enable them to survive and

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move on dry land. This

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dual life allows them to exploit

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a variety of habitats from

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underwater to terrestrial

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environments. Amphibians

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are found in almost every corner

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of the world, except for the

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polar regions, where extreme

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cold is unsuitable for their survival.

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Their habitats range from humid

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rainforests and lush woodlands

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to arid deserts and high altitude

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grasslands in

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the tropics. Many amphibians,

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such as certain frog species, can

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complete their life cycle without

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a permanent water body by

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utilizing moisture trapped in

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plant leaves and other microhabitats.

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Despite their adaptability, Amphibians

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require moist environments

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to thrive due to their permeable

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skin, which can easily lose

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moisture. This

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skin feature also enables them

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to absorb oxygen directly

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from their surroundings, but

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it does make them sensitive to environmental

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chaines and pollutants. During

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colder seasons, amphibians

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often enter a state of dormancy

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or hibernation to conserve

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energy, hiding in mud, under

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logs, or leaf litter. Frogs

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and toads make up about eighty

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percent of all amphibian species.

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Frogs are known for their long, powerful

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back legs that allow for impressive

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leaps, while toads

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typically have shorter legs and

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may prefer to walk rather than jump.

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Salamanders and newts represent

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the second major group of amphibians,

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characterized by their elongated bodies,

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short legs, and long tails

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adapted for a more aquatic or

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moist terrestrial lifestyle. The

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least known among amphibians

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are the sicilians, legless

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creatures that resemble worms or snakes

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and lead a hidden, burrowing

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life underground. Next

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we will learn a little about the life cycle

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of the frog. Did

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you know that frogs are the world

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champions of jumping. Some

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frogs can jump over twenty

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times their body length in a

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single leap. If

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a human had the same ability, they

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could jump across a basketball court

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in one bound. The

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life cycle of frogs is an incredibly

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intriguing process. In

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just a short period, they transform

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from eggs to tadpoles, then

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to froglets, and finally

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into adult frogs. This

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unique process, known as metamorphosis,

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is specific to amphibians and is

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one of the many reasons they are so

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fascinating. The

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process begins with the female

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frog laying her eggs in water,

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often laid in clumps or strings.

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These eggs are covered in a gelatinous

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substance that provides protection

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in favorable conditions. The

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eggs typically hatch within a week or

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two, depending on the species

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and the environmental temperature. What

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emerges from these eggs are not

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miniature frogs, but tadpoles,

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which look more like fish than frogs

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at this stage.

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Tadpoles are the aquatic larval

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stage of the frog. These

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little creatures have long, binned

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tails and gills for breathing

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under water. Like fish, tadpoles

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spend their days feeding on algae

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and the nutrients in the remaining gelatinous

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material of their egg cases.

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As they grow, tadpoles

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undergo a series of gradual changes

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called metamorphosis. It's

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during this stage that the remarkable

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transformation begins to take shape.

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The first noticeable change

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is the growth of hind legs, followed

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by the front legs as the tadpole

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starts to lose its fish like tail.

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Internally or inside the tadpole,

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other significant changes are happening

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too. The gills begin

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to disappear as the tadpole develops

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lungs, transforming it for

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life on land. The

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mouth of the tadpole changes, losing

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its adapted beak for scraping algae

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and gaining the typical wide mouth

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of a frog. Its

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digestive system also changes,

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from one that could handle a herbivorous

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or plant diet of algae to

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one that can digest a carnivorous

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or meat diet. As

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the metamorphosis nears completion,

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the tadpole's tail becomes smaller

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and smaller until it disappears

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completely, leaving behind

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a young frog, often

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referred to as a froglet.

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This young frog is almost a fully

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formed adult, but still

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may have some remnants of a tail that

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eventually vanishes. The

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young frog, now adapted

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to life in water and on land,

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begins the final stages of its development

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into an adult. This

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phase involves growth inside

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and the development of adult characteristics

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such as the ability to reproduce.

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Adult frogs will then continue the cycle

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by mating and laying eggs

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of their own. The

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life cycle of a frog progressing

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from egg to tadpole, toglet

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to adult shows how life

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adapts to survive in various

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environments. This

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cycle is essential to the ecosystem,

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where frogs serve as predators

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and prey, helping maintain

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ecological balance. Did

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you know that male frogs are famous

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for croaking and singing, especially

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during the mating season. They

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croak to attract female frogs

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and even have their own unique songs

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depending on the species. As

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we mentioned earlier, frogs

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diets changed dramatically as they

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progress through their life cycle. Let's

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take a closer look at what frogs eat

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at each stage of development and

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how their dietary habits help them

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thrive in diverse environments.

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As tadpoles, the diet of a

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frog is primarily herbivorous

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or plant based. Tadpoles

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feed on algae and plant matter

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found in the water where they hatch. They

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use their small, specialized

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mouths to scrape algae off

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rocks and other surfaces, and

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they also eat decaying plant

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matter. This

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plant based diet is rich in nutrients

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necessary for their rapid growth and

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development during this early

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stage of life.

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As tadpoles begin metamorphosis

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and develop legs and lungs, their

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dietary needs change. During

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this transitional phase, they start

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eating a more varied diet that includes

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small aquatic organisms such

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as tiny insects and larvae. This

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shift from the herbivorous to

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a more omnivorous or plant

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and meat diet helps them adapt

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to their changing bodies and prepares

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them for adulthood.

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Once frogs reach adulthood,

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their diet becomes primarily carnivorous

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or meat based. Adult

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frogs are known for their diverse and

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opportunistic feeding habits. They

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eat a wide range of prey, including

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insects, spiders, worms,

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and small invertebrates. Frogs

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use their long, sticky tongue to catch

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prey with remarkable speed and

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precision. When

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an unsuspecting insect comes

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within reach, the frog's

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tongue shoots out grabs

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the prey and pulls it back

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into the frog's mouth in the blink

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of an eye.

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Some larger frog species have even

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more varied diets. In

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addition to insects and small invertebrates,

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they may eat small mammals, birds,

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other amphibians, and even

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small reptiles. Frogs

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like the African bullfrog, can

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consume large prey compared

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to their size, showing

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off their adaptability and resourcefulness

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as hunters. Frogs

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are not only active hunters, but

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also use a variety of strategies

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to catch their prey. Some

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frogs wait patiently for their prey to

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come close, while others

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actively hunt and chase down

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their food. Frogs

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rely heavily on their keen sense of

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sight to detect movement, so

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they often hunt at night when many

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of their prey are active. The

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diet of frogs plays a crucial role

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in maintaining ecological balance

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By controlling insect populations,

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they help manage pests and

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contribute to the health of their environments.

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As prey for larger animals, frogs

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are an integral part of the food web,

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supporting a diverse range

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of species. Now

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let's jump right into some listener

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questions. Our

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first question comes from Charlie,

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who is five years old and from

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Malaysia. Charlie

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asks is there really a monster

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in Lockness. Lockness

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is a big, deep lake in Scotland.

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For many years people have told stories

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about seeing a huge, mysterious

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creature in the lake, which they

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call the loch Ness Monster or

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NeSSI. Some

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people think NeSSI might be a type of dinosaur

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that somehow survived, while

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others think it's just a big fish

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or something else. Scientists

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have tried to find NeSSI by looking

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in the water with special equipment like

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sonar and underwater cameras,

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but they haven't found anything that proves

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Nessie is real. They

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think that what people see might

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be big waves, floating

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logs, or even large fish

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that look like a monster from far away.

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So while it's fun to imagine

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NeSSI swimming around in Loch Ness,

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we don't have any real proof that a monster

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lives there. Thank

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you for the question, Charlie.

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Our next question is from Kira

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van Heimert, who is six years

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old and from Belgium. Kira

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asks what happens when a

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venomous spider bites? Does

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it hurt a lot? When

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a venomous spider bites, it uses

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its fangs to inject venom into

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your skin. This venom

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is a special liquid that spiders

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use to protect themselves and

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catch their food. Here's

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what happens, step by step. First,

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the spider bites and you might feel

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a sharp pinch. This is

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when the fangs pierce your skin and inject

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the venom. The

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venom starts to work right away. It

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can cause the area around the bite

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to become red, swollen, and

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sore. This is because

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the venom irritates your skin and tissues.

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The bite might hurt like a beasting

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or a bad bug bite for most people.

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Some venomous spider bites can hurt

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a lot more depending on the

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spider. For example,

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a bite from a black widow spider

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can cause severe pain that

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spreads from the bite to other parts

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of your body.

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Besides pain, venom can

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cause other reactions in your body. You

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might feel itchy, get a rash,

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or even feel sick to your stomach. Some

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people might get headaches or muscle cramps.

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In rare cases, if the venom

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is very strong, or if a person

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is allergic, it can cause more

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serious symptoms. This

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is why it's important to tell an adult and

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get medical help if you think you've

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been bitten by a venomous spider. Most

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of the time, the bite will heal in a few days.

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Keeping the bite clean and using ice

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can help reduce pain and swelling. A

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doctor can give special medicine to help

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if the bite is serious. Now,

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most spiders are harmless.

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Out of thousands of spider species,

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very few are harmful to humans. Most

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spider bites are not serious and only

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cause mild irritation. Spiders

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are important for the environment because

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they help control the population of other

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insects like flies and

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mosquitoes. Most

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spiders are not dangerous to humans

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and would rather avoid us. Thank

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you for the question, Kira. Our

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last question comes from Abigail,

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who is nine and from Ottawa.

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Abigail asks why do eyelashes

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exist. Eyelashes

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are like little protectors for your

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eyes. They have a few

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important jobs to help keep your eyes

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safe and healthy. First,

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eyelashes catch and block tiny

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particles like dirt, dust,

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and even small insects from

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getting into your eyes. This

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helps prevent irritation and keeps

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your eyes clean. Second,

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eyelashes also help to filter sunlight

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and bright light, protecting your

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eyes from getting too much light and

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helping you see better. Third,

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eyelashes are very sensitive.

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When something like a bug or a bit

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of dirt touches them, it triggers

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a reflex to blink. Blinking

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helps to quickly protect your eyes and

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remove whatever touched them. So

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eyelashes are important because

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they keep your eyes safe from harm and

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help you see comfortably. Thank

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you for the question, Abigail. Now

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for some fun facts. Did

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you know that some frogs can freeze

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and then come back to life.

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Wood frogs can survive being

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frozen solid in winter, and

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when they thaw out in spring, they

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hop away as if nothing happened. Did

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you know that frogs don't have ears

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like we do. Frogs

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have ear drums on the outside of their

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heads, and they can hear sounds

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above and below water. Did

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you know that amphibians were the first

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animals to leave the water and live

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on land. Amphibians

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were among the first creatures to transition

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from water to land, showcasing

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their amazing adaptability. Did

20:24

you know that long words can actually

20:27

make things simpler. Instead

20:30

of saying a process by which

20:32

plants used sunlight to produce food,

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scientists can just say photosynthesis

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and everyone knows what they mean. Learning

20:43

and using these words can help you understand

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and talk about science more deeply like

20:48

the experts. Did

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you know that some frogs can change

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color? Tree frogs, for example,

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can change their skin color to blend

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in with their surroundings, helping

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them hide from predators.

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In this episode, we started learning

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what makes amphibians so unique.

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We looked at the incredible life cycle of

21:14

frogs and the various environments

21:17

in which they thrive across the globe.

21:21

We also looked at what these amazing creatures

21:23

eat to fuel their leaps and hawks.

21:27

After that, we answered some questions from

21:29

Charlie Caira van Heimert,

21:31

and Abigail. Then

21:34

we shared some fun facts to satisfy

21:37

your curiosity about

21:39

frogs. Thank

21:42

you to Isabella age six

21:44

in Central New Jersey, Beverly

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five years old from Portland, Oregon,

21:51

Mattie Rose aged six and a

21:53

half in Wistern, Massachusetts,

21:55

Hudson Tias, age eight in Bakersfield,

21:59

a Rov age six, Olivia

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Campellini age seven in Montrose,

22:05

New York, i Ara holder

22:08

Orn in New Hampshire, and

22:10

Skyler Maclain from Kentucky. We

22:14

would love to get your feedback on our

22:16

show. If you have any feedback,

22:19

please send it our way. If

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you want to make sure you get all the episodes,

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or wherever your parents listen to podcasts.

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If you'd like to send us your questions, please

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22:50

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