Topic Notes: Unit 7 - Natural Selection

Evolution

The change in the genetic makeup of a population over time.

Biogeography

The study of the distribution of species and ecosystems in geographic space and through geological time.

Continental Drift

The movement of the Earth's continents over geological time, affecting species distribution.

Island Biogeography

The concept that species on islands are more similar to those on the nearest mainland.

The Fossil Record

A visual record of how organisms have changed over time, although it is incomplete.

Stratigraphy

The study of rock layers (strata) to determine the age of fossils.

Relative Dating

A method of determining the age of artifacts based on their sequence in layers.

Radiometric Dating

A method using the decay rates of radioactive isotopes to determine the exact age of an object.

Carbon-14

A radioactive isotope used for dating recent biological remains, up to about 50,000 years old.

Uranium-238

A radioactive isotope used for dating older geological formations.

Homologous Structures

Similar physical features due to shared ancestry, but may serve different functions.

Analogous Structures

Structures that serve similar functions but have different underlying anatomy and no common ancestor.

Vestigial Structures

Remnants of features that served a function in an organism's ancestors but are currently reduced or useless.

DNA/RNA and Proteins

Biochemical evidence that shows the more similar the sequences, the more recent their common ancestor.

Conserved Proteins

Proteins that evolve slowly and can be used to compare evolutionary relationships across species.

Common Ancestry

The concept that all organisms share a single common ancestor based on shared molecular and cellular features.

Genetic Code

The nearly universal system of DNA and RNA that carries genetic information in all living things.

Ribosomes

Cellular structures found in all forms of life that are the sites of protein synthesis.

Metabolic Pathways

Core biological processes like Glycolysis that suggest early evolution before oxygen was prevalent.

Antibiotic Resistance

The ability of bacteria to survive and reproduce despite the presence of antibiotics.

Pathogen Evolution

The rapid mutation of viruses, like Influenza, to evade host immune systems.

Miller-Urey Experiment

An experiment that demonstrated organic molecules could form from inorganic precursors under early Earth conditions.

RNA World Hypothesis

The theory that RNA was the first genetic material and can store information and catalyze reactions.

Teleology (Purpose)

The incorrect belief that organisms evolve 'in order to' survive, rather than through random mutations.

Common Ancestor Correction

Humans and Chimpanzees share a common ancestor, they are not direct descendants.

Population Evolution Correction

Evolution occurs in populations over generations, not in individual organisms.

Homologous vs. Analogous Correction

Homologous structures share a common ancestry, while analogous structures serve similar functions without a shared lineage.