Science & Nature
Test your knowledge of Nature's Extremes & Scientific Breakthroughs with a free trivia word search from thewordfind.com. Read each clue, work out the answer, then find it hidden in the letter grid — every puzzle is freshly generated, so no two plays are ever quite the same. Don't know an answer? Tap the hint button in-game to reveal the first letter, or just scan the grid — every answer is hiding in there somewhere. Between the clues and the full answer key below, this topic doubles as a quick study guide — good for a trivia night, a classroom quiz, or just picking up something new about Nature's Extremes & Scientific Breakthroughs along the way.
Play This Puzzle →A few sample clues
Earth's only natural satellite, visible at night, is simply called this.
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These extinct reptiles dominated Earth for over 150 million years before disappearing.
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This invisible force, described by Newton's laws, pulls objects toward one another.
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This Italian astronomer improved the telescope and provided key evidence for a sun-centered solar system.
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This towering California tree species includes the tallest living trees on Earth.
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All 100 questions in this topic, with answers — use it to study, or just browse. Every actual play of the puzzle only pulls a random handful of these into one game, so knowing them all here won't spoil which ones show up or where they're hidden in the grid. Play it here.
This colorful crustacean can throw one of the fastest, most powerful punches in the animal kingdom: the Mantis '_ _ _ _ _ _.'
SHRIMPThis diving bird of prey is the fastest animal on Earth, reaching over 240 mph in a hunting dive.
PEREGRINEThis deep-sea fish family uses a glowing lure dangling from its head to attract prey in total darkness.
ANGLERThe reticulated species of this legless reptile is the world's longest snake.
PYTHONKitti's hog-nosed species of this flying mammal is the smallest in the world by body length.
BATThis largest planet in the solar system is a gas giant with a Great Red Spot storm.
JUPITERThis gemstone, formed from extreme heat and pressure on carbon, is the hardest known natural material.
DIAMONDA tiny species of this insect-eating mammal, the Etruscan, is considered the smallest land mammal by weight.
SHREWThis bird species undertakes the longest known migration of any animal, flying pole to pole each year.
TERNThis insect can lift objects many times its own body weight, proportionally among the strongest animals alive.
ANTThis South American rainforest, the world's largest, produces roughly a fifth of the planet's oxygen.
AMAZONThis big cat is the fastest land animal, capable of speeds over 60 mph in short bursts.
CHEETAHThis African beetle is one of the heaviest insects on Earth, weighing over three ounces as a larva.
GOLIATHThis fungus, found underground and prized by chefs, can sell for thousands of dollars per pound.
TRUFFLEThis distant object, once considered the ninth planet, was reclassified as a dwarf planet in 2006.
PLUTOThis trunk-bearing mammal is the largest living land animal.
ELEPHANTAn opening in Earth's crust that releases molten rock, ash, and gases is called this.
VOLCANOThis liquid metal is the only metal that's liquid at room temperature, once used in thermometers.
MERCURYThis second planet from the sun is the hottest in the solar system due to its thick atmosphere.
VENUSThis scientist won Nobel Prizes in two different sciences — physics and chemistry: Marie '_ _ _ _ _.'
CURIEThis desert-dwelling mammal stores fat, not water, in the hump on its back.
CAMELA community of interacting organisms and their physical environment together form this.
ECOSYSTEMThis hormone, discovered in 1921, regulates blood sugar and is used to treat diabetes.
INSULINThis natural phenomenon, caused by sunlight refracting through raindrops, produces a multicolored arc in the sky.
RAINBOWThe scale most commonly used to measure the magnitude of an earthquake is named after this seismologist.
RICHTERLarge biomolecules made of amino acid chains, essential for nearly every bodily function, are called this.
PROTEINThis lightweight noble gas, lighter than air, is used to make balloons float.
HELIUMThis Australian mammal is one of only a few that lay eggs instead of giving live birth.
PLATYPUSThis ancient, horseshoe-shaped arthropod has existed largely unchanged for 400 million years and has blue blood used in medical testing: Horseshoe '_ _ _ _.'
CRABThis large flightless African bird is both the largest bird and the fastest running bird alive.
OSTRICHThis tallest grass in the world can grow up to 3 feet in a single day.
BAMBOOA massive, gravitationally bound system of stars, gas, and dust — like our own Milky Way — is called this.
GALAXYThis colorful, dancing light display near the polar regions is caused by solar particles hitting the atmosphere.
AURORAThis innermost layer of Earth is a solid ball of iron and nickel despite extreme heat.
COREThis lightweight, corrosion-resistant metal is the most abundant metal in Earth's crust.
ALUMINUMThis physicist developed the theory of relativity, including E=mc².
EINSTEINThe preserved remains or traces of an ancient organism, often found in rock, are called this.
FOSSILThis eight-armed sea creature has three hearts and blue-colored blood.
OCTOPUSThis layer of Earth beneath the crust is made of slowly flowing, semi-molten rock.
MANTLEThis nocturnal bird of prey can rotate its head up to 270 degrees to see behind itself.
OWLThis long-necked African mammal is the tallest living land animal.
GIRAFFEThis lightest and most abundant element in the universe powers stars through fusion.
HYDROGENSound cannot travel through this: the near-total absence of matter found in outer space.
VACUUMThis scale, based on water's freezing point at 0 degrees and boiling point at 100, is used by most of the world.
CELSIUSThis marine mammal has the largest brain of any animal on Earth, even larger than an elephant's — it's also known by an older whaling-era nickname.
CACHALOTThis tropical plant produces the world's largest seed, weighing up to 40 pounds.
COCODEMERThis Mexican salamander can regenerate entire limbs, and even parts of its brain and heart.
AXOLOTLThis natural satellite phenomenon occurs when Earth passes directly between the sun and the moon.
ECLIPSEThe leading scientific theory for how the universe began is called the Big '_ _ _ _.'
BANGThe basic physical unit of heredity, made of DNA, is called this.
GENEThis big cat is the only one that can roar but cannot purr, unlike smaller cats.
LIONThis precious yellow metal does not tarnish or corrode, making it valuable for millennia.
GOLDA region of spacetime with gravity so intense that nothing, not even light, can escape is called a black '_ _ _ _.'
HOLEThe first vaccine ever developed, by Edward Jenner in 1796, protected against this deadly disease.
SMALLPOXThis ancient tree species, found in California's White Mountains, includes individuals over 4,800 years old: Bristle'_ _ _ _' pine.
CONEThis three-letter molecule carries the genetic instructions for all known living organisms.
DNAEarth's crust is broken into large, slowly shifting pieces called tectonic '_ _ _ _ _ _.'
PLATESThe green species of this South American snake is the world's heaviest, especially after a big meal.
ANACONDAThe muscular organ that pumps blood throughout the body is this.
HEARTThis naturalist developed the theory of evolution by natural selection after his voyage on the HMS Beagle.
DARWINThis fourth planet from the sun is nicknamed the "Red Planet" for its rusty, iron-oxide surface.
MARSThis burrowing African mammal's name means "earth pig" in Afrikaans.
AARDVARKThis tree species, also in California, includes the largest trees on Earth by trunk volume: Giant '_ _ _ _ _ _ _.'
SEQUOIAA microscopic infectious agent, smaller than bacteria and unable to reproduce without a host cell, is called this.
VIRUSThis Antarctic seabird cannot fly but is an exceptional swimmer, some species diving over 500 meters deep.
PENGUINThe basic signaling cell of the nervous system, which transmits electrical impulses, is called this.
NEURONThis carnivorous plant snaps shut on insects that trigger tiny hairs on its leaves: Venus '_ _ _ _ _ _ _.'
FLYTRAPThis element forms the chemical basis of all known life on Earth.
CARBONThis unit measures the loudness of sound, named after the inventor of the telephone.
DECIBELA long period of significant temperature drop across the Earth is called an Ice '_ _ _.'
AGEThis English physicist and mathematician formulated the laws of motion and universal gravitation.
NEWTONThis Arctic whale is nicknamed the "unicorn of the sea" for its long, spiraled tusk.
NARWHALAlexander Fleming's accidental 1928 discovery of an antibiotic mold gave us this drug: Peni'_ _ _ _ _ _.'
CILLINThis South American rodent, often kept as a pet, is the largest living rodent in the world.
CAPYBARAThe chemical symbol for this life-essential liquid is H2O.
WATERThis element, essential for human respiration, makes up about 21% of Earth's atmosphere.
OXYGENSingle-celled microorganisms, some helpful and some harmful, found almost everywhere on Earth are called this.
BACTERIAA slow-moving mass of dense ice, formed over long periods of snow accumulation, is called this.
GLACIERThis tropical cyclone, called a typhoon in the Pacific, is fueled by warm ocean water.
HURRICANEThis flowering plant, native to Indonesia, produces the largest single flower in the world and smells of rotting flesh.
RAFFLESIAThis amphibian can breathe through its skin as well as its lungs.
FROGThis ringed planet is the second-largest in the solar system.
SATURNThis absolute-zero-based temperature scale is named after a British physicist.
KELVINThis Australian marsupial sleeps up to 22 hours a day, largely due to its low-nutrient eucalyptus diet.
KOALAThis lizard can rotate its eyes independently and change color to match its mood or surroundings.
CHAMELEONThe largest animal ever to exist on Earth is the Blue '_ _ _ _ _.'
WHALEA biological molecule that speeds up chemical reactions in living things is called this.
ENZYMEThis slow-moving reptile holds the record for longest-lived land animal, with some individuals over 190 years old.
TORTOISEThe largest living structure on Earth, visible from space off Australia's coast, is the Great Barrier '_ _ _ _.'
REEFThe organ that controls thought, memory, and the rest of the nervous system is this.
BRAINThis nearly indestructible microscopic creature, able to survive the vacuum of space, is nicknamed the water '_ _ _ _.'
BEARA massive object from space, believed to have triggered the extinction of the dinosaurs, is this.
ASTEROIDThis violent, rapidly rotating column of air, common in the central US, can level buildings in seconds.
TORNADOThis tropical bird is instantly recognizable by its oversized, colorful beak.
TOUCANA layer of gas high in Earth's atmosphere that blocks most harmful ultraviolet radiation is called the '_ _ _ _ _' layer.
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