In English, the plural of "fish" is fish when referring to individuals and fishes when referring to species. Most fish are cold-blooded, their body temperature varying with the surrounding …

Oct 28, 2025 · A fish is any of approximately 34,000 species of vertebrate animals found in the world’s fresh and salt waters. The term fish is applied to a variety of vertebrates of several …

All fish share two traits: they live in water and they have a backbone—they are vertebrates. Apart from these similarities, however, many of the species in this group differ markedly from one...

Jul 28, 2022 · The ultimate guide to fishes & fish life, including definition of a fish, fish bodies, types of fish and the life-cycle of a fish. Read on for a complete guide to ichthyology…

Jan 3, 2023 · Instead, there are 3 main classes, groups, or types of fish: bony fish (Osteichthyes), jawless fish (Agnatha), and cartilaginous fish (Chondrichthyes). Fish are the most diverse …

Fish are aquatic vertebrate animals that have gills but lack limbs with digits, like fingers or toes. Recall that vertebrates are animals with internal backbones.

May 21, 2024 · Fish are aquatic vertebrates that typically have gills, fins, and a streamlined body. They inhabit diverse environments, from freshwater rivers and lakes to salty oceans and deep …

FishBase is a global biodiversity information system on finfishes. Its initial goal to provide key facts on population dynamics for 200 major commercial species has now grown to having a …

Feb 13, 2018 · Fish biologists have described more than 30,000 species of fish in the world. Visit NPSpecies to see what species of fish are found in national parks. Scientists classify fish into …

There's plenty of fish in the sea, and scientists at NOAA Fisheries study a lot of them! Here we've gathered answers to some of the questions we get most frequently about the fish we study.