Evolution and Natural Selection Lecture Notes

A collection of vocabulary flashcards covering the key concepts of evolution, Darwin's voyage, natural selection, and the fossil record as presented in the lecture notes.

Charles Darwin

An explorer and thinker who authored the book On the Origin of Species by Means of Natural Selection after a five-year global voyage.

H.M.S. Beagle

The ship Darwin embarked on in $1831$ at the age of $22$ for a five-year voyage that changed his life.

Endemic

A term describing species that are found in only one specific spot on the planet.

Fossils

The preserved remains of ancient organisms.

Thomas Malthus

A scientist who proposed that unchecked human population growth would lead to a lack of food and living space.

Jean Baptiste Lamarck

One of the first scientists to recognize organisms change over time, though his theory of inheritance of acquired characteristics was incorrect.

Inheritance of Acquired Characteristics

Lamarck's theory that traits gained or lost through selective use or disuse of organs during an organism's lifetime could be passed to offspring.

Natural Selection

The process where individuals with favorable traits are selected by the environment to survive and reproduce more than those with less favorable traits.

Overproduction

A condition where every species tends to produce more individuals than can survive to maturity.

Variation

The many differing characteristics among individuals within a population.

Fitness

An organism's ability to survive and reproduce.

Adaptation

Any inherited characteristic that increases an organism's chance of survival.

Descent with Modification

Darwin's theory that each living species has descended, with changes, from another species over long periods.

Phylogenetic Tree

A diagram that depicts the lines of evolutionary descent of different species from a common ancestor.

Artificial Selection

The process where humans, rather than nature, choose the best adaptations or traits in organisms.

Strata

Layers of older sediments compressed over millions of years that often contain fossils.

Law of Superposition

The principle that in rock strata, the oldest layers are on the bottom and the most recent are at the creative top.

Stromatolites

Rocklike structures composed of many layers of bacteria and sediment, representing the oldest known fossils at $3.5 \text{ billion}$ years old.

Permineralization

A fossilization process where minerals in water saturate an organism and replace its bones or teeth, turning organic matter into rock.

Cast Fossils

Fossils formed when an organism decays and leaves a cavity that is later filled with minerals, replicating the shape of the organism.

Mold Fossils

Fossils consisting of an open space or cavity that represents the exact empty shape of the organism that once occupied it.

Carbon Films

Fossil imprints formed by intense heat and pressure that leave behind a thin layer of carbon in the form of a silhouette.

Body Fossils

Fossils where organic tissue, including soft tissue like skin or hair, is preserved via freezing, mummification, or encasement in amber.

Trace Fossils

Evidence of an organism's activity rather than its body, such as tracks, nests, burrows, eggs, or poop.

Relative Dating

A method used to estimate the age of a fossil by comparing its placement within rock strata.

Index Fossil

An abundant, widespread, and easily recognizable fossil that existed for a short period and is used to identify dated rock strata.

Radiometric Dating

A method used to find the exact age of fossils by determining the age of surrounding rock using radioactive isotopes.

Half-life

The length of time required for half of the radioactive atoms in a sample to decay.

Transitional Fossils

Fossils that provide evidence of the gradual changes occurring between two species over time, such as Archaeopteryx.

Vestigial Structures

Organs or structures, such as the whale pelvis, that have lost all or most of their original function through evolution.

Homologous Structures

Structures between species that are similar in anatomy and arrangement due to shared common ancestry.

Analogous Structures

Structures between species that are similar in function but not anatomy, such as the wings of a bird and a bee.

Adaptive Radiation

A process where a small group of species evolves over a short time into several different forms that live in different ways.