Explore clear, practical articles about animals and the way they live.
No, jellyfish do not have brains, but they do have nervous systems. Instead of a centralized brain like those found in humans, fish, and many other animals, jellyfish possess networks of nerve cells distributed throughout their bodies. These nerve networks help them sense their surroundings, coordin
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What's Inside a Sea Urchin?Although sea urchins have a simple appearance from the outside, their internal anatomy is remarkably specialized. Their organs are arranged inside a rigid shell called the test, which is co···
Sea Urchin Habitat at a GlanceSea urchins belong to the class Echinoidea and are found in every major ocean on Earth. Although they all require saltwater to survive, different species have adapted to a wide variety of ma···
What Animals Eat Sea Urchins?Sea urchins may look well protected because of their round bodies, hard shells, and sharp spines, but many ocean predators have evolved special adaptations to hunt and eat them. Some animals ···
Quick answerThe hot dog-shaped structure in an animal cell is most likely the mitochondrion. In many school diagrams, mitochondria are drawn as small red, orange, or pink oval shapes with wavy lines inside. Their shape c···
Yes, insects are animals. Insects belong to the animal kingdom, Animalia, because they are multicellular living organisms that eat organic matter, move during at least part of their life cycle, develop from embryos, and ···
A fry is a baby fish. Learn what “fry” means, why young fish are called fry, and the differences between fry, larvae, alevins and fingerlings.
The “hot dog thing” in an animal cell is usually the mitochondrion. If there is more than one, they are called mitochondria. Mitochondria are bean-shaped or sausage-shaped organelles that help turn food molecules and o···
Squirrel poop and rat poop can look similar, but there are useful clues. Squirrel droppings are usually oval, rounded, slightly thicker, and often found in attics, near nests, or under entry points. Rat droppings are usu···
A black panther is not a separate species, while a jaguar is a real big cat species. In the Americas, a “black panther” usually means a melanistic jaguar: a jaguar with extra dark pigment. In Africa or Asia, a black pa···
Learn what rats eat, including grains, fruit, meat, garbage, pet food, and more, plus how wild and urban rats survive as highly adaptable omnivores.
Learn what captive axolotls eat, including worms, pellets, feeding schedules, portion sizes, foods to avoid, and how diet changes with age.
Some animals really do have blue blood. The best-known examples include horseshoe crabs, octopuses, squids, cuttlefish, and some other marine invertebrates. Their blood looks blue because it uses a copper-based oxygen-ca···
Learn how sharks see, smell, and hear underwater, which sense is strongest, and how their sensory system helps them hunt and survive.
The phrase “blind as a bat” is one of the most common animal myths in English, but it is wrong. Bats are not blind. In fact, all bats can see, and many species use vision together with hearing, smell, and—when they ha···
Discover animals that live in Germany’s Black Forest, including red deer, wild boar, wildcats, lynx, wolves, capercaillie, owls and other native wildlife.
The blue whale is the largest whale and largest living animal on Earth. See its maximum length, weight, size comparisons, diet and conservation status.
There is no scientifically proven “shortest-memory animal.” Goldfish remember far longer than 3 seconds. See what research says about bees, dogs and other animals.