Archaea

Bacteria

Eukaryotes

Archaea

Bacteria

Eukaryotes

All unobserved swans are white

Plants grow faster under blue light than under red light

Beauty is the most important trait in flowers

Ionic bonds within a single water molecule

Hydrogen bonding among water molecules

Nonpolar covalent bonds between oxygen and hydrogen

Glycolysis in the cytosol (input: CO2; outputs: glucose); pyruvate oxidation in the lysosome (outputs: lactate); oxidative phosphorylation at the plasma membrane (outputs: NADPH)

Glycolysis in the cytosol (input: glucose; outputs: pyruvate, ATP, NADH); pyruvate oxidation and the citric acid cycle in the mitochondrial matrix (outputs: CO2, NADH, FADH2, ATP/GTP); oxidative phosphorylation at the inner mitochondrial membrane (inputs: NADH/FADH2 and O2; outputs: ATP and water)

Glycolysis in the mitochondrial matrix (input: pyruvate; outputs: CO2 and NADH); citric acid cycle in the cytosol (outputs: glucose); oxidative phosphorylation in the nucleus (outputs: ATP only)

Glycolysis in the cytosol (input: fatty acids; outputs: acetyl-CoA); citric acid cycle in the ER (outputs: O2); oxidative phosphorylation in the chloroplast (outputs: ATP)

They remain as a six‑carbon glucose molecule until the citric acid cycle

They are converted directly into ethanol during pyruvate oxidation

They become two molecules of pyruvate (3 carbons each), then each loses one carbon as CO2 to form acetyl-CoA (2 carbons)

They are completely oxidized to CO2 during glycolysis

It directly phosphorylates ADP to ATP at the electron carriers

It creates a proton gradient across the inner mitochondrial membrane that drives ATP synthase (chemiosmosis)

It splits water to release oxygen needed for ATP formation

It transports glucose into the matrix where ATP is assembled

A process that uses the citric acid cycle to make ATP without electron transport

An anaerobic process that regenerates NAD+ by reducing pyruvate (e.g., to lactate or ethanol) so glycolysis can continue

A pathway that increases O2 production to fuel oxidative phosphorylation

A mechanism that stores pyruvate in the peroxisome for later respiration

Light‑independent reactions generate light energy that powers the photosystems

Light‑dependent reactions in thylakoid membranes produce ATP and NADPH; the Calvin cycle in the stroma uses ATP and NADPH to fix CO2 into sugars

Both sets occur only in the stroma and directly release O2 from sugar oxidation

Light‑dependent reactions occur in the stroma and fix CO2; the Calvin cycle in thylakoids generates ATP and NADPH

Photosystems contain only carotenoids and lack primary electron acceptors

PSII and PSI are identical complexes that use the same reaction center pigment and do not require antenna pigments

Antenna pigment complexes funnel energy to reaction centers (P680 in PSII, P700 in PSI), which pass electrons to primary electron acceptors

Single chlorophyll molecules (P450) in each photosystem directly fix CO2 without antenna pigments

Electrons move from PSI to PSII to split water; the released oxygen powers ATP formation

Linear electron flow from PSII through cytochrome b6f to PSI builds a proton gradient for ATP synthesis, and PSI reduces NADP+ to NADPH

ATP and NADPH are formed when NADH donates electrons directly to ATP synthase

Cyclic electron flow through PSII produces NADPH while PSI makes ATP by substrate‑level phosphorylation

CO2 reacts with NADPH to form glucose in the reaction center

CO2 is fixed to RuBP by rubisco; ATP and NADPH reduce 3‑phosphoglycerate to G3P; ATP is used again to regenerate RuBP

CO2 is stored in thylakoids; ATP and NADPH split water; RuBP is regenerated without ATP

CO2 is oxidized by PSI; ATP phosphorylates glucose directly; NADPH is exported to mitochondria

Both use rubisco’s oxygenase activity to remove excess CO2

C4 plants rely on cyclic electron flow only; CAM plants halt the Calvin cycle until rainy conditions

C4 plants use spatial separation (PEP carboxylase in mesophyll; Calvin cycle in bundle‑sheath cells) and CAM plants use temporal separation (stomata open at night, malate stored for daytime CO2 release)

Both open stomata widely during midday to increase O2 uptake for rubisco

Photosynthesis and respiration are identical except for the organelles in which they occur

Photosynthesis creates ATP by substrate‑level phosphorylation only, while respiration uses light energy to power electron transport

Photosynthesis reduces CO2 to energy‑rich carbohydrates using light energy, whereas respiration oxidizes carbohydrates to CO2 to produce ATP; both use electron transport chains and proton gradients

Both processes oxidize glucose to CO2 but photosynthesis occurs only at night and does not use electron transport chains

Depolarization, repolarization, and hyperpolarization

Reception, transduction, and response

Secretion, endocytosis, and exocytosis

Translation, replication, and transcription

Endocrine (gap junctions), synaptic (hormonal circulation), paracrine (internal receptor signaling), autocrine (surface receptor signaling)

Endocrine (long‑distance via bloodstream), paracrine (local diffusion), synaptic (cell‑to‑cell via neurotransmitters), autocrine (self‑signaling)

Paracrine (long‑distance via blood), endocrine (contact‑dependent), synaptic (diffusion through ECM), autocrine (neighbor signaling only)

All signaling mechanisms operate over identical distances and differ only in receptor type

GPCRs signal by permanently binding ATP to ion channels without G proteins

Ligand binding activates the GPCR, which promotes GDP‑to‑GTP exchange on a heterotrimeric G protein; the Gα or Gβγ subunits regulate effectors; signaling terminates when GTP is hydrolyzed

Ligand binding causes the receptor to become a transcription factor that directly replicates DNA

G proteins are activated by phosphorylation of the ligand rather than nucleotide exchange

Surface receptors enter the nucleus to bind DNA, whereas intracellular receptors stay at the membrane

Intracellular receptors require endocytosis to activate G proteins, while surface receptors do not

Intracellular receptors bind small hydrophobic ligands and often act as transcription factors; surface receptors bind hydrophilic ligands and initiate cytoplasmic signaling cascades

Both receptor types bind only peptide ligands and function exclusively at the plasma membrane

Large, charged peptide hormones that cannot cross membranes

Small, nonpolar, hydrophobic molecules such as steroid hormones and thyroid hormones

Carbohydrates that bind cell‑surface integrins

Hydrophilic neurotransmitters that act through ion channels only

Ligand polarity has no influence on receptor location or interaction

Nonpolar ligands can diffuse across membranes to reach intracellular receptors, whereas polar ligands cannot cross easily and therefore bind surface receptors

Polar ligands freely cross membranes and bind intracellular receptors; nonpolar ligands are excluded and bind surface receptors

Only charged ligands can activate any receptor type

Chromatin is an RNA complex containing genes; sister chromatids form only during meiosis

Genes exist only outside chromosomes and are not part of chromatin

Genes are arranged along DNA molecules packaged as chromatin; after DNA replication, each chromosome consists of two sister chromatids joined at the centromere

Sister chromatids are different chromosomes with unrelated genes

G1 (chromosome segregation), S (RNA synthesis), G2 (cell death), M (organelle duplication)

G1 (cell growth), S (DNA replication), G2 (preparation for mitosis), M (mitosis and cytokinesis)

G0 (DNA replication), G1 (mitosis), G2 (fertilization), M (growth)

S (cell growth), G1 (DNA replication), G2 (meiosis), M (metabolic rest)

Overexpression of DNA repair genes; treatments inhibit repair enzymes to increase mutations

Activating mutations in proto‑oncogenes and loss of tumor suppressors disrupt checkpoints; targeted therapies (e.g., kinase or CDK inhibitors) aim to restore control or block hyperactive signaling

Excessive meiosis in somatic cells; treatments promote gamete formation

Enhanced checkpoint activity and increased apoptosis; treatments increase mitogenic signaling

Haploid cells have two sets of chromosomes; diploid cells have one set

Haploid and diploid cells contain identical chromosome numbers

Haploid cells are only found in plants; diploid cells are only found in animals

Haploid cells contain one set of chromosomes (n), whereas diploid cells contain two sets (2n)

All haploid cells are diploid until fertilization

A gamete is a specialized haploid reproductive cell, whereas a haploid cell can be any cell type with one chromosome set

A haploid cell is always a zygote, whereas a gamete is not

Gametes are always diploid, whereas haploid cells are somatic

Chromatids exist only in haploid cells, while chromosomes exist only in diploid cells

After DNA replication, a single chromosome consists of two sister chromatids; a chromatid is one of the identical DNA copies

A chromosome is always composed of a single chromatid

A chromatid is an entire genome, whereas a chromosome is a small DNA fragment

Sister chromatids come from different parents; homologous chromosomes are identical copies

Sister chromatids are identical DNA copies of a single chromosome joined at the centromere; homologous chromosomes are a pair from each parent with the same genes but possibly different alleles

Homologous chromosomes are joined at centromeres, whereas sister chromatids are never connected

Sister chromatids have different genes, whereas homologous chromosomes contain identical genes

Mitosis produces four daughter cells; meiosis produces two identical diploid cells

Mitosis and meiosis both produce haploid gametes in one division

Mitosis involves one division producing genetically identical diploid daughter cells; meiosis involves two divisions producing genetically diverse haploid gametes

Mitosis increases genetic diversity via crossing over; meiosis does not

Meiosis I separates sister chromatids; meiosis II separates homologous chromosomes

Meiosis I separates homologous chromosomes into different daughter cells; meiosis II separates sister chromatids

Neither division changes chromosome associations

Both divisions separate homologous chromosomes only

Ploidy is reduced during meiosis II when sister chromatids pair

Ploidy is unchanged throughout meiosis

Ploidy is reduced from diploid to haploid during meiosis I when homologous chromosomes segregate to different daughter cells

Ploidy increases during meiosis I due to chromosome replication

Meiosis has a single division; mitosis has two divisions

Meiosis includes homologous recombination and independent assortment that increase genetic variation; mitosis does not

Mitosis always produces haploid spores; meiosis always produces diploid clones

Both processes require fertilization to complete division

Elimination of centromeres and irreversible chromatid fusion

Crossing over during prophase I, independent assortment of homologs at metaphase I, and random fertilization

Cytokinesis patterns and spindle elongation

DNA replication without proofreading and fixed chromosome alignment

Premature cytokinesis causing triploidy in all gametes

Nondisjunction of homologous chromosomes leading to aneuploidy such as trisomy

Kinetochores binding microtubules correctly, causing chromosomal loss

Excessive crossing over leading to tetraploidy

Characters are determined by proteins only; traits are determined by RNA only

A character is a heritable feature (e.g., flower color), whereas a trait is a specific variant of that character (e.g., purple)

Traits are non‑heritable, while characters are environmental

A character is a specific variant, whereas a trait is the general feature

Genotype is the physical appearance; phenotype is the DNA sequence

Genotype is the genetic makeup (allele combination); phenotype is the observable expression of the genes

Genotype describes environmental effects; phenotype describes chromosome number

Genotype changes every mitosis; phenotype never changes

Alleles are proteins; dominance refers to higher protein concentration only

An allele is a variant of a gene; a dominant allele determines the phenotype in heterozygotes; a recessive allele is masked in heterozygotes

Dominant alleles always produce lethal phenotypes; recessive alleles never do

An allele is a whole chromosome; dominant alleles exist only in homozygotes; recessive alleles exist only in haploids

Homozygous means two different alleles; heterozygous means identical alleles

Homozygous applies only to dihybrids; heterozygous applies only to monohybrids

Homozygous means two identical alleles for a gene; heterozygous means two different alleles

Homozygous refers to phenotype only; heterozygous refers to genotype only

Monohybrid crosses require testcrosses; dihybrid crosses do not

A monohybrid cross follows one gene with two alleles; a dihybrid cross follows two genes simultaneously

Monohybrid crosses occur in diploids; dihybrid crosses occur only in haploids

A monohybrid cross involves two genes; a dihybrid involves one

Proteins that mark the location of ribosomes on mRNA

Identifiable DNA sequence features (e.g., SNPs, microsatellites) used to track inheritance of linked genes or loci

Metabolic intermediates that tag chromosomes for degradation

Any visible trait regardless of genetic basis

Cross with a heterozygote; a 3:1 recessive:dominant ratio indicates homozygous dominant

Cross the individual with another dominant; all recessive offspring indicate homozygous dominant

Cross the individual with a homozygous recessive; a 1:1 dominant:recessive offspring ratio indicates heterozygosity, whereas all dominant offspring indicate homozygous dominant

Self‑fertilize the individual; any recessive phenotype proves homozygosity

Allele segregation is caused by crossing over in meiosis II

Allele pairs separate during gamete formation so each gamete carries one allele; this reflects separation of homologous chromosomes in meiosis I

Alleles always remain paired in gametes; separation occurs only after fertilization

Allele pairs segregate during mitosis rather than meiosis

Independent assortment occurs only in mitosis; Mendel inferred it from monohybrid crosses

Alleles of different genes always travel together; dihybrid crosses showed complete linkage in all cases

Alleles of different genes assort independently during gamete formation when genes are on different chromosomes; dihybrid cross results supported independent assortment

Independent assortment states that one gene controls all traits; Mendel observed single‑gene inheritance only

They never recombine and therefore always show 0% recombination.

They tend to be inherited together because they reside on the same chromosome and show recombination frequencies less than 50%.

They assort independently because crossing over always separates them in every meiosis.

They exhibit recombination frequencies exactly equal to 50%, indicating complete independence.

X-linked alleles are never expressed in females due to X-inactivation.

Males are hemizygous for X-linked genes and express recessive alleles from a single X, whereas females typically require two copies to express a recessive trait.

Females are hemizygous for X-linked genes and therefore always express recessive alleles.

X-linked traits are transmitted only from fathers to sons.

All offspring of an affected parent are affected regardless of the other parent’s genotype.

Affected individuals are present in every generation and both sexes are equally affected.

Affected offspring often appear from two unaffected parents and the trait can skip generations.

Only males are affected and the trait is passed from mothers to sons.

Meselson–Stahl experiment demonstrating semiconservative replication.

Chargaff’s rules showing base-pair ratios differ among species.

Hershey–Chase blender experiment showing DNA from phage enters bacteria and directs phage production.

Griffith’s experiment showing transformation without identifying the transforming principle.

RNA primers are synthesized in the $$3' \to 5'$$ direction and extended in the same direction.

New strands are synthesized in the $$5' \to 3'$$ direction while reading the template in the $$3' \to 5'$$ direction.

DNA polymerases synthesize both DNA and RNA in either direction depending on the template.

New strands are synthesized in the $$3' \to 5'$$ direction while reading the template in the $$5' \to 3'$$ direction.

Ligase unwinds the helix; primase seals nicks; DNA polymerase I synthesizes the leading strand; helicase adds RNA primers.

Helicase unwinds the double helix; primase synthesizes RNA primers; DNA polymerase III extends strands; ligase seals nicks between Okazaki fragments.

Topoisomerase adds RNA primers; helicase seals nicks; DNA polymerase III removes primers.

Primase extends Okazaki fragments; ligase synthesizes primers; helicase proofreads new DNA.

Meselson–Stahl showed semiconservative replication of DNA.

Beadle and Tatum showed that specific gene mutations in Neurospora blocked single steps in metabolic pathways that could be rescued by adding the missing intermediate.

Chargaff showed species-specific base composition in DNA.

Hershey–Chase showed DNA enters bacteria and directs phage production.

Transcription synthesizes RNA from a DNA template; translation synthesizes a polypeptide using mRNA as the template.

Transcription synthesizes DNA from an RNA template; translation synthesizes RNA from a polypeptide.

Transcription and translation both synthesize DNA from RNA templates.

Transcription synthesizes proteins directly; translation synthesizes DNA using tRNA.

Eukaryotes use multiple RNA polymerases and require general transcription factors at promoters; bacteria use a single RNA polymerase with sigma factor.

Bacteria use multiple RNA polymerases with transcription factors; eukaryotes use a single polymerase with sigma factor.

Both eukaryotes and bacteria require no protein factors to initiate transcription.

Eukaryotic transcription occurs in the cytoplasm; bacterial transcription occurs in the nucleus.

Introns are removed and exons are spliced together, with addition of a 5' cap and a poly(A) tail.

Exons are removed and introns are spliced together without any end modifications.

A 3' cap is added and introns are translated into peptide tags.

RNA processing is absent; mRNAs are used exactly as transcribed.

Eukaryotic ribosomes typically recognize the 5' cap and scan to the start codon; bacterial ribosomes bind the Shine–Dalgarno sequence on mRNA.

Both eukaryotic and bacterial ribosomes recognize the Shine–Dalgarno sequence.

Bacterial initiation requires a 5' cap; eukaryotes use a Shine–Dalgarno sequence.

Initiation is identical in both systems and does not involve mRNA features.

A base substitution that converts a sense codon into a stop codon.

A base substitution that changes one amino acid to another without altering protein length.

A base substitution that preserves the same amino acid due to redundancy.

An insertion or deletion of three nucleotides that adds or removes one amino acid.

The operator is a DNA site where a regulatory protein (repressor) binds to block RNA polymerase from transcribing genes downstream of the promoter.

The operator is the site where RNA polymerase binds to initiate transcription.

The operator encodes the repressor protein.

The operator is an mRNA sequence that recruits ribosomes.

Negative control: the lac repressor binds the operator when lactose is absent; positive control: CAP–cAMP activates transcription when glucose is low.

Negative control: CAP–cAMP binds the operator when glucose is high; positive control: the repressor activates transcription when lactose is present.

Negative control: the lac repressor activates transcription in the presence of lactose; positive control: CAP–cAMP represses transcription when glucose is low.

Negative control: sigma factor binds the operator; positive control: lactose removes RNA polymerase from the promoter.

Post-transcriptional regulation of pre-mRNA processing.

Transcriptional regulation of promoter choice.

Translational regulation of ribosome activity.

Post-translational regulation of protein folding.

Histone acetylation generally opens chromatin to promote transcription, whereas certain histone methylation patterns can repress transcription.

Histone acetylation compacts chromatin to repress transcription, while methylation always activates transcription.

Chromatin structure has no impact on gene expression in eukaryotes.

DNA supercoiling only occurs in prokaryotes and cannot affect eukaryotic transcription.

MicroRNA-mediated repression of specific mRNAs affecting their stability or translation.

Enhancer-bound transcription factors increasing RNA polymerase recruitment.

CAP–cAMP activation of the lac operon in bacteria.

DNA replication initiation at origins during S phase.

A donor cell transfers DNA, often an F plasmid or chromosomal segment, to a recipient through a conjugation pilus, resulting in new genetic combinations.

Naked DNA is taken up from the environment without cell-to-cell contact.

Bacteriophages package bacterial DNA and deliver it to new cells during infection.

Cells fuse and form diploid zygotes to recombine homologous chromosomes.

Bacteria can incorporate naked DNA from the environment into their genome, producing genetic recombinants.

DNA is transferred via a conjugation pilus.

Phage infection delivers viral genomes only, never bacterial DNA.

Transformation requires viral capsids to package donor DNA.

Bacteriophages mediate transfer of bacterial DNA between cells, generating recombinants.

Naked DNA is taken up from the environment.

DNA is transferred through direct cell-to-cell contact via a pilus.

Transduction occurs only with eukaryotic viruses and not with bacteriophages.

A virus consists of a nucleic acid genome enclosed by a protein capsid, with structures that may be helical, icosahedral, or enveloped.

A virus is a cell with a nucleus and mitochondria that lacks a cell wall.

All viruses are non-enveloped and have identical icosahedral capsids.

Viruses contain only proteins and lipids without any nucleic acid genome.

Virulent phages perform only a lytic cycle; temperate phages can enter a lysogenic cycle in which their genome integrates into the host and can later induce the lytic cycle.

Both virulent and temperate phages are strictly lysogenic and never lyse cells.

Temperate phages are always lytic and cannot integrate into host genomes.

Virulent phages integrate into host genomes permanently and never lyse cells.

Viruses rely on host cellular machinery, offer few unique drug targets, and often mutate rapidly, reducing the effectiveness of antivirals.

Antibiotics are universally effective against viral enzymes.

Viruses do not replicate inside host cells and are easy to target.

All animal viruses have identical replication strategies, making one drug sufficient for all.

Cut plasmid and target DNA with matching restriction enzymes; ligate the gene into the plasmid; transform competent bacteria; select transformants with antibiotic; grow colonies to amplify the cloned gene

Use RNA polymerase to insert the gene into a plasmid; heat-shock cells without selection; pick any colony and assume cloning succeeded

Mix intact genomic DNA with plasmids and incubate; any gene will spontaneously enter the plasmid; plate without antibiotics to avoid selection bias

Electroporate naked genomic DNA into bacteria; the genome integrates into the plasmid during replication without enzymes

Short DNA primers complementary to sequences flanking the target

Thermostable DNA polymerase that resists denaturation

Magnesium ions that enable polymerase catalysis

dNTPs that provide building blocks for synthesis

PCR amplification followed by allele-specific probe hybridization or sequencing

Light microscopy of blood smears to visualize the mutation directly

Growing the patient’s cells in culture to observe colony morphology

Measuring total DNA concentration with a spectrophotometer

Multiple independent STR loci vary greatly among individuals, producing a highly distinctive multilocus profile

STRs are located only in coding regions, so they directly reveal a suspect’s phenotype

STR profiles change rapidly within an individual over time, allowing time-of-crime estimation

STR analysis requires whole-genome sequencing, making false matches impossible

Chain-terminating dideoxynucleotides create length-varied fragments that are separated to read base order

Nanopore current changes are measured as DNA passes through a pore to call bases

Random cloning of fragments followed by restriction mapping reveals sequence

Antibody binding to bases reveals the base identity directly under a microscope

Transcriptome

Proteome

Metabolome

Genome

Microbiome

Lamarck emphasized inheritance of acquired characteristics, whereas Darwin emphasized natural selection acting on heritable variation

Both proposed natural selection as the sole driver, but Lamarck considered it stronger

Darwin argued traits acquired during an organism’s lifetime are inherited, Lamarck rejected this

Lamarck and Darwin both denied any role for heritable variation

Field observations reveal ecological interactions, behavior, and selection pressures, whereas genomics identifies specific genetic variants and pathways underlying phenotypic differences

Genomics replaces the need for field data because DNA sequences alone reveal all ecological relationships

Field observations mainly document DNA sequence, while genomics measures behavior in the wild

Neither approach provides causal insights; both are purely descriptive

Observed genotype frequencies differ significantly from Hardy–Weinberg expectations given the allele frequencies

Population is large with random mating and no selection

Allele frequencies remain constant across generations

No mutation, migration, or drift is detected

Mutation

Gene flow (migration)

Genetic drift

Natural selection

Nonrandom mating

Drift in small populations accelerates loss of genetic diversity and can fix deleterious alleles, reducing adaptive potential

Small populations always experience stronger natural selection that eliminates harmful alleles

Genetic drift increases heterozygosity and thus guarantees resilience

Conservation success depends only on habitat size, not population genetics

Selection favors extreme phenotypes at both ends and reduces intermediate phenotypes

Selection favors one extreme, shifting the mean

Selection favors intermediate phenotypes, reducing variance

Mate choice leads to differential reproductive success based on traits that attract partners

Heterozygote advantage maintains both alleles because heterozygotes have the highest fitness

Directional selection consistently favors a single allele across environments

Genetic drift in very large populations increases allele fixation

High mutation rate alone guarantees equal allele frequencies

Biological species concept: difficult to apply to asexual organisms and fossils

Morphological species concept: never subjective because all traits are equally informative

Phylogenetic species concept: requires no data on relationships among taxa

Biological species concept: primarily based on shared ecological niche rather than reproductive isolation

Temporal isolation due to different mating seasons

Hybrid sterility in offspring

Hybrid inviability after fertilization

Hybrid breakdown in later generations

Geographic isolation followed by genetic divergence via drift and/or selection, often in small, isolated populations

Sympatric divergence due to polyploidy, mainly in large, panmictic populations

Hybridization merges populations, then reproductive isolation evolves

Geographic isolation is unnecessary; gene flow promotes speciation

Smaller populations experience stronger genetic drift, and different environments impose distinct selection, promoting divergence when gene flow is absent

Large populations always diverge faster because drift is stronger

Gene flow between isolated populations accelerates divergence

Population size has no effect on drift or selection

Mass extinctions reduce diversity short term but can create ecological opportunity that triggers adaptive radiations, increasing diversity over time

Adaptive radiations always decrease diversity by eliminating competitors

Mass extinctions permanently reduce diversity with no subsequent recovery

Adaptive radiations occur only when environments remain unchanged

The Pax6/eyeless gene drives eye development across distant taxa; misexpression can induce ectopic eyes

Eye formation requires unique, unrelated genes in each animal lineage

Conserved Hox genes are absent from animals with eyes

Appendage development genes evolve too rapidly to be conserved

Rank-based hierarchy can obscure evolutionary relationships and may not reflect true phylogeny

It uses DNA sequences for every taxon, making it infallible

It rejects the concept of genera and species entirely

It requires monophyly for all ranks, preventing any misclassification

Nodes represent common ancestors; sister taxa share a more recent common ancestor with each other than with more distant taxa

Trees depict a ladder of progress from primitive to advanced forms

Longer branches always mean higher fitness

Tips that are adjacent on the page are always closest relatives regardless of branching

A taxon that includes a common ancestor and some, but not all, of its descendants

A taxon that includes all descendants of a common ancestor

A grouping that combines taxa from multiple unrelated lineages without their most recent common ancestor

A clade defined by unique synapomorphies with complete descendant inclusion

The tree requiring the fewest evolutionary changes across all characters

The tree with the most characters mapped regardless of change count

The tree with the longest branches visually

The tree that maximizes the number of taxa per clade

Map the trait onto the phylogeny and place its origin on the branch leading to the most recent common ancestor of all taxa that possess the trait, minimizing extra origins and losses

Assign the trait to the earliest diverging tip regardless of distribution

Place the trait’s origin at every node to avoid assumptions

Infer the trait evolved independently in every taxon that has it