Animal_Vertebrate_Essay

Animal Vertebrate Essay Almost all vertebrates reproduce sexually and all take care for their offspring in different ways. Some, including lizards, fish, and amphibians sometimes develop from unfertilized eggs. Birds use internal fertilization to reproduce. They lay eggs. This suits their environment because they need to fly, and to fly efficiently they need to have as little weight as possible. The bird’s eggs are similar to reptiles. They have a hard outside shell. Most birds incubate their eggs until they hatch. This period could be from thirteen to fifty days. When a bird is ready to hatch it uses its beak to poke a hole and prod itself out of its shell. Then it collapses until its feathers dry out. Some birds can take care of themselves after a couple of hours, but most depend on their parents for care and food for days or even weeks. Most amphibians reproduce externally, but some have internal fertilization. The females can release as many as 200 eggs at a time, which the male fertilizes. This suits their environment because it is aquatic and the eggs that the females release into the eggs, reptiles, birds, because, amphibians, mammals, fish, water, different, environment, developed, young, type, time, need, internal, care, muscles, mammal, aquatic, while, warm, vertebrates, protect, plants, move, lot, longer, live, heat, heart, fertilization, excrete, cool, blood