Evolution Word Search With Natural Selection and Fossil Lists

A printable evolution puzzle and answer key for the week your class meets Darwin, natural selection and the fossil record.

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Evolution Word Search

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0 of 16 words found

MAVARIATIONOYSO

RCXIHOMOLOGOUSA

AMGMFRPDNZDXLGA

NUAOCSELECTIONT

CTLHPOPULATIONF

EAARNREMBRYOETI

STPPARLKGLFAEGT

TIATLEXTINCTJEN

OOGPTFOSSILEHVE

RNOTTSIGYNBRTTS

VESTIGIALHBSCDS

EZOIQIUYDEBRKRF

LEUNNTHFTRAITMM

ROYPXDARWINXREE

OATSPECIATIONNB

This grid is wider and taller than its box. Slide it to see every letter.To drag, hold the first letter for a moment, then slide.Keyboard: Tab to the grid, arrow keys to move, Enter on the first and last letter.

SelectionSELECTION
VariationVARIATION
MutationMUTATION
TraitTRAIT
FitnessFITNESS
InheritINHERIT
PopulationPOPULATION
FossilFOSSIL
HomologousHOMOLOGOUS
VestigialVESTIGIAL
EmbryoEMBRYO
AncestorANCESTOR
ExtinctEXTINCT
SpeciationSPECIATION
DarwinDARWIN
GalapagosGALAPAGOS

16 of 24 words from the Evolution Key Terms list.

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Answer key: Evolution Word Search

MAVARIATIONOYSO

RCXIHOMOLOGOUSA

AMGMFRPDNZDXLGA

NUAOCSELECTIONT

CTLHPOPULATIONF

EAARNREMBRYOETI

STPPARLKGLFAEGT

TIATLEXTINCTJEN

OOGPTFOSSILEHVE

RNOTTSIGYNBRTTS

VESTIGIALHBSCDS

EZOIQIUYDEBRKRF

LEUNNTHFTRAITMM

ROYPXDARWINXREE

OATSPECIATIONNB

SELECTION, VARIATION, MUTATION, TRAIT, FITNESS, INHERIT, POPULATION, FOSSIL, HOMOLOGOUS, VESTIGIAL, EMBRYO, ANCESTOR, EXTINCT, SPECIATION, DARWIN, GALAPAGOS

Next step Play fossil evidence bingo with these words Build a puzzle from your own evolution unit notes

All 126 words

Natural Selection 25

Adaptation A feature shaped over many generations because it helps with a job, such as a thick fur coat.
Breeding Choosing which plants or animals become parents, as farmers do to get the features they want.
Camouflage Coloring or shape that lets an animal match its background and stay unseen.
Competition The contest among living things for food, space and other needs that are in short supply.
Environment Everything around a living thing, from climate and food to enemies.
Evolution Change in the inherited features of a population over many generations.
Fitness How well a living thing does at leaving young in the next generation.
Generation One step in a family line: parents are one, their young are the next.
Heritable Able to be passed from parents to their young through genes.
Inherit To receive a feature from a parent through genes.
Mate A partner for producing young.
Mimicry Looking like another living thing, as a harmless hoverfly looks like a wasp.
Mutation A copying slip or damage that alters DNA. It is where brand-new inherited differences begin.
Peppered moth An English insect whose dark form became common when soot blackened trees in the 1800s.

Show all 126 words (112 more)

Natural Selection, continued

Pigeon A bird kept in many fancy forms. Darwin questioned its keepers while working on his theory.
Population A group of one kind of living thing that lives in one area and breeds together.
Predator A hunter, such as a hawk or a wolf, that catches and eats other animals.
Prey An animal that is hunted and eaten by another animal.
Reproduce To make young of the same kind.
Resistance The ability of some bacteria to survive an antibiotic, a change that has been watched as it spread.
Selection Nature's sorting: individuals with helpful features leave more young than the rest do.
Struggle Darwin's word for the contest to stay alive: 'the ... for existence'.
Survival Staying alive, which a living thing must do long enough to have young.
Trait A feature of a living thing, such as beak shape or fur color.
Variation The differences among members of one population, such as size, color or speed.

Evidence for Evolution 27

Amber Fossilized tree resin, sometimes with an ancient insect sealed inside.
Analogous Alike in use but evolved separately, like the wings of a bird and the wings of an insect.
Anatomy The structure of a body and its parts. Comparing it across species points to shared ancestry.
Ancestor A living thing from long ago from which later ones are descended.
Archaeopteryx A feathered, bird-like dinosaur with teeth and claws that lived about 150 million years ago.
Biogeography The science of which plants and animals live where on Earth, and how they got there.
Embryo A living thing in its earliest stage of growth, compared across species for clues to ancestry.
Extinct No longer living anywhere on Earth, like the trilobites.
Fossil A bone, shell, leaf print or footprint of ancient life, kept in rock for ages.
Homologous Inherited from a shared ancestor, like the arm bones of a human, a bat and a whale.
Layer One sheet of rock in a cliff face. Fossils in a lower one are usually older.
Limb An arm, a leg or a flipper. The front ones of bats, whales and horses share one bone plan.
Molecular Describes evidence read from DNA: species that are close relatives have more of it alike.
Paleontologist An expert who reads ancient life from bones, shells and tracks in rock.
Pelvis The hip bones. Whales keep small ones though their hind legs are gone.
Radiometric A kind of dating that finds a rock's age from the steady decay of radioactive atoms.
Skeleton The frame of bones in a body. Lucy's was found about 40 percent complete.
Skull The bones of the head. Lucy's was small, like an ape's, though she walked upright.
Strata Layers of sedimentary rock, stacked with the oldest at the bottom.
Superposition The rule that in undisturbed rock layers the older ones lie beneath the younger ones.
Tailbone The small bone at the base of the human spine, a leftover from primate ancestors with tails.
Tiktaalik A fossil fish about 375 million years old with sturdy bones in its fins, found in Canada in 2004.
Transitional Describes a fossil that shows the change from an older form to a later one.
Trilobite An extinct sea arthropod with a body in three lobes, common as a fossil.
Vestigial Left over from an ancestor and now smaller and of less use, like a whale's hip bones.
Whale A sea mammal that breathes air. Fossils from Pakistan trace its ancestors from land to sea.
Wing What a bird, a bat or an insect flies with. Each group evolved flight on its own.

Speciation and Family Trees 27

Allopatric Describes new species forming after a population is split by geography.
Barrier Something that keeps two populations apart, such as a river, a canyon or a sea.
Bottleneck An event that shrinks a population sharply, as when northern elephant seals fell to about 30.
Branch One line on an evolutionary tree, standing for a lineage through time.
Clade One ancestor together with every one of its descendants: a whole branch of the tree of life.
Cladogram A branching diagram that shows how groups of living things are related.
Common ancestor An organism from which two or more later lines are both descended.
Convergent Describes evolution that gives unrelated groups alike features, such as flight in bats and birds.
Derived trait A newer form of a feature, changed from the older form that the ancestors had.
Divergence One ancestral line splitting into two or more that grow less and less alike.
Endemic Found in one small region and nowhere else, as the marine iguana is on the Galapagos.
Founder effect The shift in inherited traits that follows when only a few settlers start a new population.
Gene flow The spread of inherited traits between populations, as when pollen blows in from the next valley.
Gene pool Every version of every inherited trait found in one population, counted together.
Genetic drift Chance changes in a population's inherited traits from one generation to the next, by luck alone.
Interbreed To have young with members of another population or group.
Isolation Being cut off from the rest of a population, by a sea or a mountain range for example.
Migration Animals or seeds moving from one population into another, carrying their genes along.
Niche The role a species plays in its home: what it eats, where it lives and when it is active.
Node A fork on a family tree: the spot where one line splits into two or more.
Outgroup A lineage outside the group being studied, placed on a family tree for comparison.
Phylogeny The pattern of family ties among living things, often drawn as a tree.
Root The base of an evolutionary tree, the oldest point, from which every line on it descends.
Speciation The forming of new species, as parts of one population stop breeding with each other.
Species A group of living things that can breed with one another in nature.
Tip The end of a line on an evolutionary tree, where a living or extinct group is named.
Tree of life The one great branching diagram that shows how all living things on Earth are related.

Darwin, Wallace and the Beagle 24

Anning Mary, the English fossil hunter of Lyme Regis who dug out an ichthyosaur skeleton at age 12.
Archipelago A chain or cluster of islands, such as the Galapagos or Hawaii.
Barnacle A small sea animal in a hard case. Darwin's work on it helped win him the Royal Medal in 1853.
Beagle The British survey ship that carried Darwin around the world from 1831 to 1836.
Cactus A prickly desert plant. Some Galapagos finches punch holes in its fruit with their long beaks.
Cuvier The French naturalist who established that species really do die out.
Darwin Charles, the English naturalist who sailed on the Beagle and published his theory in 1859.
Ecuador The South American country that the Galapagos belong to.
Finch A small Galapagos bird. About 18 species differ most in how big and what shape their beaks are.
Galapagos Volcanic Pacific islands that belong to Ecuador. The Beagle reached them in 1835.
Hutton The Scottish geologist, born in 1726, who argued that the Earth must be extremely old.
Iguana A large lizard. The marine kind lives only on the Galapagos and feeds on algae in the sea.
Island A piece of land with water on every side, where a cut-off population can change on its own.
Lamarck The French thinker who argued early for evolution and held that acquired features are inherited.
Lyell The Scottish geologist whose Principles of Geology Darwin read during his years at sea.
Malthus The English writer on population whose 1798 essay both Darwin and Wallace read.
Mockingbird The Galapagos bird that Darwin noticed differed from one island to the next.
Naturalist A person who studies plants and animals in nature, the post Darwin held at sea.
Shell The hard cover of a tortoise, domed on the Galapagos islands with wet highlands.
Ship A large sea vessel. The Beagle was one, with Robert FitzRoy in command.
Theory A broad explanation for many facts that can be tested with evidence.
Tortoise A giant Galapagos reptile. The shape of its shell differs from island to island.
Voyage A long journey by sea. Darwin's lasted almost five years.
Wallace Alfred Russel, the English naturalist who reached the same theory on his own, in print in 1858.

History of Life on Earth 23

Ape A primate with no tail, such as a gorilla or a chimpanzee.
Asteroid A space rock. The impact of a huge one is thought to have ended the age of dinosaurs.
Cambrian The period when most major animal groups first appear in the fossil record.
Coelacanth A lobe-finned fish known only from fossils until one was caught off South Africa in 1938.
Dinosaur One of a group of reptiles. All but the birds died out about 66 million years ago.
Dodo A flightless bird of Mauritius, last reliably seen in 1662.
Eon The largest unit of geologic time. Only four are defined.
Epoch A unit of geologic time smaller than a period. We live in the Holocene one.
Era The second largest unit of geologic time, such as the Mesozoic.
Feathers The body covering of birds, also found on fossils of many other dinosaurs.
Geologic Describes the very long time scale of Earth's history, read from its rocks.
Hominin A word for humans and our closest extinct relatives, such as Lucy's kind.
Horse A mammal whose fossil record runs 50 million years, from a dog-sized forest animal to one toe.
Human Our own species, Homo sapiens, the only living member of its genus.
Index fossil The remains of a species typical of one span of geologic time, used to date rock layers.
Living fossil A species alive today that looks much like relatives known only from ancient rocks.
Lucy The nickname of a fossil skeleton about 3.2 million years old, found in Ethiopia in 1974.
Mammoth An extinct woolly elephant. A last herd held on at Wrangel Island until roughly 4,000 years ago.
Mass extinction A time when a large share of all species die out close together, as 66 million years ago.
Neanderthal An extinct kind of human that lived in Europe and Asia until about 40,000 years ago.
Period A unit of geologic time smaller than an era. The Jurassic is one of 22.
Primate A member of the mammal group that holds lemurs, monkeys and humans.
Tetrapod A vertebrate with four limbs, or one whose ancestors had them, such as a snake.

How this list was compiled: Own work: the word list and every clue were written for this page. The facts in the clues were checked on 2026-09-19 against the Understanding Evolution glossary of the University of California Museum of Paleontology (https://evolution.berkeley.edu/glossary/) and Wikipedia, among them https://en.wikipedia.org/wiki/Natural_selection and https://en.wikipedia.org/wiki/Charles_Darwin. Spellings follow the American Heritage Dictionary (https://www.ahdictionary.com/). All people named are historical. Some clues were reworded on 2026-09-20, and any fact that changed was checked against Wikipedia the same day. Licence: own work

How it works

This evolution word search fills a 15 by 15 grid with 16 of 24 key terms, Adaptation, Fossil and Speciation among them. Natural Selection, Evidence for Evolution and 6 more lists hold 126 words, each with a clue.

Read the full guide

One list for each part of the unit

The Start from a list row, under the puzzle, has 8 lists. Five are themed: Natural Selection (25 words), Evidence for Evolution (27), Speciation and Family Trees (27), Darwin, Wallace and the Beagle (24) and History of Life on Earth (23). For a natural selection word search, choose the first, and the title on the sheet changes to match. Easy Evolution holds 26 words of 3 to 5 letters, such as Prey, Finch and Clade.

Mass extinction sits in History of Life on Earth, away from Extinct, because one can be ringed inside the other.
Eleven entries have spaces and hide with them dropped: GENEPOOL, TREEOFLIFE. Evolution Key Terms and Easy Evolution are single words.
Tick Show clues, not words: Paleontologist becomes "An expert who reads ancient life from bones, shells and tracks in rock."

Questions and answers

Does the evolution puzzle come with an answer key?

Yes. The key prints as page 2 and fits only the grid it came with, because New puzzle draws 16 other words each time. Print the pair together, on Letter or A4, or pick Save as PDF in the print window.

Which lists are easier and which are harder?

Easy Evolution and Natural Selection use the shorter, earlier words, such as Trait, Prey and Survival. Speciation and Family Trees adds Allopatric, Cladogram and Genetic drift, and Hard Evolution has 49 words of 9 to 14 letters.

Are genetics words such as allele and genotype in the puzzle?

No. Alleles, Punnett squares and the ranks of classification are on the biology word search and are left out here on purpose. To add a few, type them at the end of the word list under the grid.

Did Darwin come up with natural selection alone?

No. Alfred Russel Wallace reached the same theory on his own, and it was in print in 1858. Both names are key terms here, and Darwin, Wallace and the Beagle adds the survey ship that carried Darwin around the world from 1831 to 1836.

All 126 words

Natural Selection 25

Natural Selection, continued

Evidence for Evolution 27

Speciation and Family Trees 27

Darwin, Wallace and the Beagle 24

History of Life on Earth 23

How it works

One list for each part of the unit

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