Animal Quiz

The Animal Kingdom: Life in All Its Diversity

The animal kingdom (Animalia) contains over 8 million estimated species, of which only about 1.2 million have been formally described and named by scientists. Animals range from microscopic water bears (tardigrades) that can survive in space to the blue whale - The largest animal ever to have lived on Earth, reaching up to 30 meters in length and 180 tons in weight. Animals are defined as multicellular, eukaryotic organisms that are heterotrophic (they consume other organisms for energy).

Some remarkable animal facts: cheetahs are the world's fastest land animals (up to 120 km/h), but can only sustain this speed for about 30 seconds; octopuses have three hearts and blue blood (due to copper-based hemocyanin instead of iron-based hemoglobin); a group of crows is called a "murder"; butterflies taste with their feet; and the mantis shrimp can see 16 types of color receptors compared to humans' three. Try the Biology Quiz for broader life science knowledge, or explore the Interesting Facts Quiz for more surprising truths.

Many animals exhibit remarkable behaviors and adaptations: migratory birds navigate thousands of miles using Earth's magnetic field; electric eels can generate up to 600 volts of electricity to stun prey; archerfish shoot precise jets of water to knock insects off overhanging branches; and cleaner shrimp set up "cleaning stations" where they remove parasites from larger fish that come seeking their services. The diversity of life on Earth remains one of science's most awe-inspiring subjects, with new species being discovered every year.