Final answer:
Amphibians adapted to land through the development of lungs for air breathing, protective skin, eyelids, and a transition from fins to limbs for mobility. Specializations like sticky tongues aid in their carnivorous diet. However, these adaptations are not tailored to tundra environments, as they generally prefer moist and temperate regions.
Step-by-step explanation:
Amphibians were the first vertebrates to live on land, and evolving from their water-bound predecessors required a host of adaptations. Notably, the amphibians developed lungs for breathing air, as their ancestral gills were no longer sufficient on land. This change allowed for greater range and access to new nutrient sources, with fewer predators. Additionally, adaptations such as protective skin, eyelids, and a vertebral column supported their terrestrial lifestyle. The shift from fins to limbs allowed them to move effectively on land, navigating the diverse topography beyond the water's edge.
Modern amphibians, as members of the subclass Lissamphibia, have permeable skin with mucus glands that facilitate cutaneous respiration, exchanging oxygen and carbon dioxide directly with their environment. Their ecology is widespread, inhabiting freshwater, moist terrestrial habitats, and they are notably absent only from Antarctica. Being carnivorous, adult amphibians utilize specialized features like sticky tongues to capture prey, further distinguishing them from their ancestors.
Although amphibians have adapted incredibly well to land, the tundra presents extreme challenges that do not favor typical amphibian life. The adaptations mentioned above do not include strategies specifically for surviving the harsh tundra conditions, highlighting the amphibians' preference for more temperate or tropical environments where moisture is abundant, allowing them to thrive.