Gerincteleneknél

Gerincteleneknél refers to the group of animals that lack a vertebral column, commonly known as invertebrates. This incredibly diverse phylum encompasses a vast majority of animal species on Earth, estimated to be around 95%. Invertebrates exhibit an extraordinary range of forms, sizes, and life cycles, inhabiting virtually every environment from the deepest oceans to the highest mountains.

Key characteristics of invertebrates include the absence of a backbone or any internal skeletal structure made of bone. Instead, many invertebrates have exoskeletons, which are external hard coverings that provide support and protection, such as the chitinous shells of insects and crustaceans. Others rely on hydrostatic skeletons, where internal fluid pressure provides support, as seen in earthworms and jellyfish. Some, like sponges, lack true tissues and organs altogether.

The invertebrate kingdom is broadly categorized into numerous phyla, including Arthropoda (insects, spiders, crustaceans), Mollusca (snails, clams, squids), Annelida (segmented worms), Cnidaria (jellyfish, corals), Echinodermata (starfish, sea urchins), and Porifera (sponges). Each phylum possesses unique anatomical and physiological features. Their ecological roles are equally varied, functioning as primary producers, consumers, decomposers, and essential components of food webs across all ecosystems. Their study is fundamental to understanding biodiversity, evolution, and the functioning of the natural world.