Get concise answers to common questions about animals, their behavior, biology and everyday wildlife misconceptions, with helpful context.
What is a bioactive terrarium, and does it really clean itself? Learn how springtails, isopods, live plants and substrate work together—and what maintenance is still required.
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Learn what fruits hamsters can eat, how much to serve, which fruits to avoid, and why dwarf hamsters need extra care with sugary treats.
Why did Sacabambaspis go extinct? Fossils show a local mass-death event in Bolivia, but the true cause of the genus’s extinction remains uncertain.
How long can frogs hold their breath underwater? Learn why there is no single time, how frogs breathe through their skin, and why species and temperature matter.
The Annoyance of Constant BeepingA solar mole repeller should operate quietly and consistently according to its design. Some models intentionally emit short audible beeps during activation or testing, while others work a···
Why Does a "Wire Missing" Error Occur?Most robotic lawn mowers navigate by detecting a continuous electrical signal traveling through a boundary wire installed around the mowing area.If that loop is interrupted···
Why Are Ants Invading Your Beehive?Ants are attracted to beehives because they provide abundant food and shelter. Honey, pollen, sugar syrup, wax scraps, and even dead insects can all attract foraging ants.Healthy coloni···
How Does a Koi Pond Autofill Valve Work?An autofill valve automatically maintains the pond's water level by opening when the water drops below a preset level and closing once the desired level is reached. Most system···
Sea Urchin Facts at a GlanceFeatureFactAnimal GroupEchinodermsScientific ClassEchinoideaNumber of Living SpeciesAbout 950–1,000 speciesHabitatAll major oceansMain DietAlgae, kelp, seaweedMain PredatorsSea otters, fish, ···
What Do Sea Urchins Eat?Sea urchins play an important role in marine food webs because they help control algae growth. Most species spend much of their lives slowly grazing across the seafloor, feeding on plants and othe···
What Animals Are Closely Related to Sea Urchins?Sea urchins belong to the phylum Echinodermata, an ancient group of marine invertebrates that has existed for more than 500 million years. Every living echinoderm shares a ···
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···