Evolution Notes (9th Grade H)

Basically AP bio on less crack

Evolution

Concept that species change over time.

Main Points of Evolution

Species characteristics change over time, linked to mutational changes within the gene pool.

Natural Selection

‘Mother Nature’ selects traits that are best relative to the environment at the time.

Old Earth Theory

The belief that the Earth is very old due to the vast changes in species over time.

DeVignoles

Estimated the Earth to be approximately 5800 years old based on biblical and ancient references.

Bishop James Ussher

Declared the Earth to be 6000 years old based on biblical calculations.

John Lightfoot

Claimed God created the Earth on October 23, 4004 B.C. at 9:00 a.m.

Relative Dating

Determining the relative age of materials by comparing their positions.

Law of Superposition

In layers of rocks, the oldest layers are at the bottom and the youngest at the top.

Absolute Dating

Method that attempts to determine the true age of a material, usually involving radioactive dating.

Radioactive Decay

Process by which radioactive isotopes release energy at a steady rate until they transform into a different element.

Half-Life

The time required for half of the original quantity of a radioactive isotope to decay.

Oldest Rocks

Zircons in western Australia, dating to approximately 4.4 billion years old.

Meteorites

Rocks from space that consistently date to approximately 4.6 billion years old.

Carbon-14 Dating

Method of dating fossils by studying the decay of Carbon-14.

Uranium-Lead (U-Pb)

A radioisotope used to date rocks older than Carbon-14's effective range.

Potassium-Argon (K-Ar)

A dating method used for rocks older than 100,000 years.

The Coacervate Theory

Theory proposed by Oparin about Earth's early atmosphere contributing to the origin of life.

Organic Soup

The mixture of molecules within early oceans where life is believed to have originated.

Evidence to Support Evolution

Fossil record demonstrates a progression in diversity and complexity over 3.5 billion years.

Vestigial Organs

Structures within species that have no apparent function today.

Homologous Organs

Organs with similar anatomical forms that differ in function.

Analogous Organs

Organs serving similar functions but differing in structure.

Genetic and Biochemical Similarity

DNA analysis allows comparisons among species showing biochemical similarities.

Early Development Similarity

Related species show similarities in early embryonic development.

Lamarck’s Theory of Evolution

Three sub-theories: Need, Use/Disuse, and Acquiring Traits.

Theory of Need

Organisms change based on needs created by environmental pressures.

Theory of Use/Disuse

Traits can be altered through behavioral influences.

Theory of Acquiring Traits

Altered traits can be inherited by offspring.

Alfred Russel Wallace

Naturalist whose observations led to thoughts on evolutionary theory parallel to Darwin.

Charles Darwin

Published 'On the Origin of Species', detailing evolution by natural selection.

Darwin’s Major Points

Overproduction, Variation, Struggle for Survival, and Natural Selection.

Scopes Trial

John Scopes was tried for teaching evolution, raising questions about First Amendment rights.

Punctuated Equilibrium

Theory explaining long periods of stability interrupted by rapid changes.

Mutation

Introduces inheritable genetic variations into a population.

Migration

Movement of individuals that alters gene pools.

Isolation

Separation affecting evolutionary trajectories.

Divergent Evolution

One species evolves into multiple forms showing homologous characteristics.

Convergent Evolution

Unrelated species adapt similar traits through environmental needs.

Microevolution

Small-scale evolutionary changes occurring within a species.

Macroevolution

Large-scale evolutionary changes that occur over long time periods.

Speciation

The process by which new species arise from existing species.

Adaptive Radiation

The rapid evolution of diversely adapted species from a common ancestor.

Coevolution

The process where two or more species influence each other's evolutionary pathway.

Genetic Drift

Random changes in allele frequencies within a population.