Contrast between invertebrates and vertebrates
Invertebrates, such as insects and mollusks, do not have a backbone and typically have simpler nervous systems with ganglia or nerve nets. Vertebrates, including fish, amphibians, reptiles, birds, and mammals, have a spinal column, centralized nervous system, and exhibit more complex behaviors. Invertebrates show diverse reproductive strategies, while vertebrates primarily reproduce sexually with internal fertilization. The evolutionary history of invertebrates spans millions of years, adapting to various environments, while vertebrates have evolved from early chordates with significant adaptations to different habitats.
