Comprehensive Biology and Evolution Concepts for Independent Learners

Material Naturalism

The idea that only natural, physical things exist.

Methodological naturalism

Science explains the world using only natural causes.

Occam's Razor

The simplest explanation is usually the best.

Karl Popper

Scientist who said hypotheses must be falsifiable.

Science

Science is the process of testing explanations with evidence.

Hypothesis

A testable explanation for an observation.

Null Hypothesis

The claim that there is no effect or no difference.

Replicate

Repeating an experiment to confirm results.

Dependent Variable

The thing you measure in an experiment.

Independent Variable

The thing you change in an experiment.

Control

A group that does not receive the treatment.

Treatment

The condition applied to the experimental group.

Simple linear regression

A test that shows how one variable predicts another.

Correlation

A relationship or association between two variables.

p-value

The probability your results happened by chance.

Sham control

A fake treatment to imitate the experiment without the active part.

Inductive reasoning

Using specific observations to create a general idea.

Deductive reasoning

Using a general rule to predict a specific result.

Historical science

Science that studies past events (like fossils or geology).

Observational science

Science based on watching and recording natural events.

Experimental science

Science that tests cause-and-effect with controlled experiments.

Discovery science

Science that focuses on describing patterns through observation.

Double blind design

Neither researchers nor subjects know who got the treatment.

Placebo effect

People improve simply because they believe they got treatment.

N (sample size)

Total number of subjects in all groups.

Theory

A well-supported explanation backed by evidence.

Biotic potential

The maximum number of offspring a species could produce.

Teleological

An explanation that describes a trait or behavior in terms of its purpose or goal

Expectation bias

When someone sees what they expect to see instead of what is actually there.

Aristotle

Early philosopher who believed species were fixed and unchanging.

August Weismann

Scientist who showed that acquired traits cannot be inherited.

Alfred Russel Wallace

Came up with natural selection independently of Darwin

Patrick Matthew

Earlier thinker who described natural selection before Darwin, but didn’t get credited.

Jean-Baptiste de Lamarck

Suggested organisms inherit traits gained in life.

Charles Darwin

Scientist who developed the theory of natural selection.

Georges Cuvier

Scientist who studuie fossils to show species go extinct, supported catastrophism

Charles Lyell

Argued Earth changes slowly (uniformitarianism)

Catastrophism

The idea that Earth changed through sudden disasters.

Gradualism

The idea that Earth and life change slowly over long periods.

Uniformitarianism

The idea that the same natural processes occur today and in the past.

Thomas Malthus

Economist who said populations grow faster than resources.

Aposematic coloration

Bright warning colors showing toxicity.

Ontogenetic

Related to an organism's development from embryo to adult.

Allopatry

Populations living in separate geographic areas.

Sympatry

Populations living in the same geographic area.

Gene

A DNA segment that codes for a trait.

Allele

A version of a gene.

Central dogma

DNA → RNA → Protein.

Cell Theory

All living things are made of cells and come from cells.

Theory of Inheritance

Genes are passed from parents to offspring.

Telegony

The false belief that previous mates influence a female's offspring.

Evolutionary Theory

The explanation that species change over time through natural processes.

Fitness

An organism's ability to survive and reproduce.

Adaptation

A trait that increases survival or reproduction.

Artificial selection

Humans choose which individuals breed.

Natural selection

Nature selects individuals with better traits.

Microevolution

Small genetic changes within a population.

Macroevolution

Large-scale changes that produce new species.

Ontogeny

The development of an organism from birth to adulthood.

Phylogeny

The evolutionary history of a species.

Transitional fossils

Fossils showing traits between ancestral and modern forms.

Biogeography

The study of where species live and why.

Homologous chromosomes

Chromosome pairs with the same genes from each parent.

Autosomes

Non-sex chromosomes.

Sex chromosomes

Chromosomes that determine biological sex (X/Y).

Telomere

The end cap of a chromosome.

Centromere

The chromosome region where sister chromatids attach.

Analogous traits

Traits that look similar but evolved independently.

Convergent evolution

Unrelated species evolve similar traits.

Vestigial structure

A leftover structure with little or no function.

Atavism

A random reappearance of an ancestral trait.

Comparative anatomy

Comparing body structures to study evolution.

Mitosis

Cell division that makes identical body cells.

Meiosis

Cell division that makes gametes with half the chromosomes.

Dioecious

Species with separate male and female individuals.

Monoecious

Species with both sexes in one individual.

Frequency-dependent selection

The value of a trait depends on how common it is.

Mixed ESS

A stable strategy where multiple behaviors coexist.

Sexual reproduction

Offspring have genes from two parents.

Asexual reproduction

Offspring come from one parent and are clones.

Parthenogenesis

Females produce offspring without fertilization.

Polyembryony

One fertilized egg splits into many embryos.

Fission

One organism splits into two.

Fragmentation

A piece breaks off and grows into a new organism.

Simultaneous hermaphrodite

An organism with both male and female functions at once.

Serial hermaphrodite

An organism that switches sex over its lifetime.

Peramorphosis

Development goes beyond the adult form of ancestors.

Hypermorphosis

A developmental process continues longer than normal.

Neoteny

Adults keep juvenile features.

Paedomorphosis

Any situation where adults look more juvenile than ancestors.

Progenesis

An organism becomes sexually mature earlier than normal.

Allometry

Different body parts grow at different rates.

Post-displacement

A developmental process starts later than normal.

Heterochrony

Evolutionary change caused by altered timing of development.

Acceleration

A trait develops faster than in ancestors.

Pre-displacement

A developmental process starts earlier than normal.

Phenotype

Physical traits an organism shows.

Genotype

The genetic makeup that produces traits.

Dominant gene

A gene expressed with only one copy.

Recessive gene

A gene expressed only with two copies.