Final answer:
Amphibians faced challenges in respiration and reproduction as they evolved from water to land.
Step-by-step explanation:
Amphibians faced several challenges as they evolved, particularly in their transition from water to land. Two major challenges include:
- Respiration: Amphibians had to adapt their respiratory systems to function in a terrestrial environment. While aquatic amphibians primarily respire through their skin and gills, terrestrial amphibians developed lungs to extract oxygen from the air.
- Reproduction: Amphibians initially relied on water for reproduction, laying eggs in water or possessing aquatic larvae. However, as they moved onto land, they had to find ways to reproduce without returning to the water. This led to the evolution of various reproductive strategies, such as direct development or the deposition of eggs in moist areas.