Aquatic and Marine Biology

When threatened, some species of sea cucumbers can eject their sticky, toxic internal organs (a process called evisceration) to distract or entangle predators. The lost organs are later regenerated without causing permanent harm to the sea cucumber.

While a general group of fish is called a school, a specific group of trout is referred to as a hover. Other terms like smack (jellyfish) and mob (kangaroos) refer to different animal groups.

In seahorses, the female deposits her eggs into the male's brood pouch, where he fertilizes them, carries them to term, and eventually undergoes contractions to give birth to the young.

Jellyfish are simple aquatic organisms that lack a centralized brain, a heart, and a circulatory system. Instead, they rely on a decentralized nerve net to sense and react to their environment.

The vast majority of described marine species belong to the animal kingdom, particularly marine invertebrates such as mollusks, crustaceans, and corals. While marine microbes and protists are extremely abundant in individual numbers, animals represent the majority of classified species.

Fescue is a genus of terrestrial evergreen perennial tufted grasses found on land. Kelp, sea grass, and sargassum are all marine organisms (algae or true plants) that grow in the ocean.

Plankton (specifically phytoplankton) are primary producers that use photosynthesis to make food, forming the base or lowest trophic level of the marine food chain in the Arctic.

Bycatch refers to any unwanted fish and other marine creatures trapped by commercial fishing nets during fishing for a different species. This includes non-target fish, undersized fish, and protected marine animals.

Overfishing is the removal of a species of fish from a body of water at a rate greater than that at which the species can naturally replenish its population.

While many fish stocks are overfished or fully fished, not all species are overfished; some fisheries are managed sustainably and maintain healthy population levels.

Ticks are parasites because they live on the bodies of host animals and feed on their blood, harming the host in the process. Amphibians, beetles, and fish are general categories of animals that are typically free-living.

Jellyfish have existed for at least 500 million years, making them older than sharks, which appeared about 400 to 450 million years ago. Dinosaurs and humans appeared much later in Earth's history. This makes jellyfish one of the oldest multi-organism animal groups on the planet.

The Latin word for crab is 'cancer'. This is also the name of the constellation and the astrological sign represented by a crab.

Sharks are cartilaginous fish, meaning their skeletons are made of cartilage rather than bone. Unlike marine mammals like whales and dolphins, sharks breathe through gills and do not nurse their young with milk.