Marine invertebrates are animals that live in the ocean and do not have a backbone. This diverse group includes species such as jellyfish, octopuses, sea urchins, and coral. They play essential roles in marine ecosystems, contributing to the food web and helping to maintain the health of ocean environments. These creatures can be found in various habitats, from shallow coastal waters to the deep sea. Marine invertebrates exhibit a wide range of shapes, sizes, and behaviors, making them fascinating subjects for study. Their adaptability allows them to thrive in different conditions, showcasing the diversity of life in our oceans.