Frogs are amphibians, meaning they can live both on land and in water. There are over 7,000 species of frogs worldwide, and they are especially common in moist environments. Frogs are vertebrates, and their life cycle includes three main stages: egg, larva (tadpole), and adult. They usually lay their eggs in water. Tadpoles breathe through gills, while adult frogs use both their lungs and skin to absorb oxygen.<br /><br />One of the most distinctive features of frogs is their long hind legs, which allow them to jump great distances and swim efficiently. Their tongues are sticky and adapted to catching insects such as flies. Frogs are mostly carnivorous, feeding on insects, worms, and small invertebrates. Some larger species can even eat small vertebrates like mice.<br /><br />Their skin is delicate and permeable to water, which is why they require moist habitats. Some species have toxic skin, which protects them from predators. A well-known example is the poison dart frog from South America.<br /><br />Frogs are highly sensitive to environmental changes and are therefore considered biological indicators of ecosystem health. They are also known for their vocalizations; male frogs call out with distinctive sounds during the mating season to attract females.<br /><br />In recent years, frog populations have been declining due to habitat loss, pollution, and climate change. This is alarming for ecosystems, as frogs play a critical role in the food chain as both predators and prey.
