Darwin

Front

Evolution Noun

---

[ev-uh-loo-shun]

Back

Evolution

---

The process by which different kinds of living organisms are thought to have developed and diversified from earlier forms.

---

Example: This diagram shows a 'tree of life,' illustrating how different groups of animals, like fish, reptiles, and mammals, evolved from a common ancestor over time.

Front

Natural Selection Noun

---

[nach-er-uhl suh-lek-shun]

Back

Natural Selection

---

The process where organisms better adapted to their environment tend to survive and produce more offspring, passing on their traits.

---

Example: This image shows that giraffes with longer necks can reach food and survive (check mark), while those with shorter necks cannot, demonstrating natural selection.

Front

Adaptation Noun

---

[ad-ap-tey-shun]

Back

Adaptation

---

An inherited characteristic or trait that increases an organism's chance of survival and reproduction in its specific environment.

---

Example: This gecko's skin color and pattern are an adaptation that allows it to blend in with the rocky environment, a form of camouflage to avoid predators.

Front

Variation Noun

---

[vair-ee-ey-shun]

Back

Variation

---

The natural differences in traits that exist among individuals within a population or species, providing the raw material for evolution.

---

Example: Darwin's finches show variation, as different finches have different beak shapes and sizes, which are adapted to the specific foods they eat.

Front

Mutation Noun

---

[myoo-tey-shun]

Back

Mutation

---

A permanent alteration in the DNA sequence that makes up a gene, which can lead to new heritable traits.

---

Example: A change (mutation) in a gene's DNA sequence can cause it to produce an abnormal protein, which is different from the normal protein.

Front

Fossil Noun

---

[fos-uhl]

Back

Fossil

---

The preserved remains, impression, or trace of a once-living organism from a past geological age, found in rock.

---

Example: This diagram shows different types of fossils found in distinct layers of rock, demonstrating that different organisms lived at different times in Earth's history.

Front

Extinct Adjective

---

[ik-stingkt]

Back

Extinct

---

The state of a species, family, or other group of organisms having no living members left anywhere in the world.

---

Example: This fossil shows the preserved skeleton of an animal that lived long ago and is now extinct, providing key evidence for Darwin's theory of evolution.

Front

Common Ancestor Noun

---

[kom-uhn an-ses-ter]

Back

Common Ancestor

---

An ancestral species from which two or more different species evolved over time through divergence and natural selection.

---

Example: This diagram shows that different species, like humans and chimpanzees, share a common ancestor from which they both evolved over millions of years.

Front

Artificial Selection Noun

---

[ahr-tuh-fish-uhl suh-lek-shun]

Back

Artificial Selection

---

The process by which humans intentionally breed plants or animals to select for and propagate specific, desirable traits.

---

Example: Humans selected specific traits from the wild Brassica plant, like its leaves or flower buds, to breed different vegetables like kale, broccoli, and cabbage.

Front

Homologous Structures Noun

---

[ho-mol-uh-guhs struk-cherz]

Back

Homologous Structures

---

Structures in different species that are similar due to common ancestry but may have evolved to perform different functions.

---

Example: This image shows that the forelimbs of a human, cheetah, whale, and bat have a similar underlying bone structure, indicating a common ancestor.