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Science // Animals of the World
The Red Queen HypothesisIntroduce the Red Queen hypothesis — species must keep evolving just to maintain fitness relative to co-evolving partners; describe predator-prey arms races…
Ages 11 to 12ConceptScience // Animals of the World
The Biodiversity CrisisQuantify the current biodiversity crisis: extinction rates 100-1000x the background rate; explain methods for measuring biodiversity loss (species-area…
Ages 12 to 14ConceptScience // Animals of the World
Sexual SelectionExplain sexual selection as a form of natural selection: runaway selection for peacock tails, bird of paradise displays, and frog calls; explain kin selection…
Ages 12 to 13ConceptScience // Animals of the World
Deep-Sea SurvivalExplain how deep-sea animals cope with crushing pressure (no gas-filled spaces, flexible proteins, pressure-adapted enzymes); describe thermoregulation extremes…
Ages 12 to 13ConceptScience // Animals of the World
Grouping Species Using DNAExplain cladistics: organisms are grouped by shared derived characters, not just similarity; how phylogenetic trees are built using molecular data (DNA sequence…
Ages 13 to 14ConceptScience // Dinosaurs & Paleontology
Dinosaur-to-Bird TransitionTrace the evidence for the dinosaur-to-bird transition in depth: feathered theropods from the Liaoning Formation (China), the mix of dinosaur and bird features…
Ages 11 to 13ConceptScience // Dinosaurs & Paleontology
Radiometric DatingExplain how radiometric dating works — radioactive isotopes decay at a known rate (half-life), so measuring the ratio of parent to daughter isotope in a rock or…
Ages 11 to 13ConceptScience // Dinosaurs & Paleontology
Reconstructing Ancient EcosystemsReconstruct an ancient ecosystem using multiple independent lines of evidence: isotope analysis of teeth to infer diet and migration, bone histology (growth…
Ages 12 to 14MethodScience // Dinosaurs & Paleontology
Mass Extinctions in Earth HistoryCompare the five major mass extinction events in Earth history (End-Ordovician, Late Devonian, End-Permian, End-Triassic, K-Pg), describe proposed kill…
Ages 12 to 14ConceptScience // Dinosaurs & Paleontology
Megafauna Extinction & De-ExtinctionEvaluate the debate over what drove Pleistocene megafauna to extinction — human overkill, climate change, or a combination — using evidence from fossil records…
Ages 13 to 14Thinking skillScience // Ecosystems & Habitats
Food Webs & InterdependenceConstruct and interpret food webs showing the interdependence of organisms in an ecosystem, explaining how a change in one population affects others
Ages 11 to 12ConceptScience // Ecosystems & Habitats
Pollination & Pollinator DeclineExplain the importance of insect pollination for plant reproduction and human food security, and discuss the consequences of pollinator decline
Ages 11 to 12ConceptScience // Ecosystems & Habitats
Energy Loss Between LevelsExplain how energy is transferred between trophic levels in a food chain, why energy is lost at each stage, and use pyramids of biomass/numbers to represent…
Ages 11 to 12ConceptScience // Ecosystems & Habitats
The Water CycleDescribe the water cycle, tracing water through evaporation, condensation, precipitation, surface runoff, and transpiration in plants, explaining how the sun…
Ages 11 to 12ConceptScience // Ecosystems & Habitats
Extinction & Rapid ChangeExplain how environmental change can outpace a species' ability to adapt through natural selection, leading to extinction, using historical and contemporary…
Ages 12 to 14ConceptScience // Ecosystems & Habitats
The Carbon CycleDescribe the carbon cycle, tracing carbon through photosynthesis, respiration, feeding, decomposition, and combustion, and explain the role of each process
Ages 12 to 13ConceptScience // Ecosystems & Habitats
How Natural Selection WorksExplain natural selection as the mechanism of evolution: heritable variation + competition for resources + differential survival and reproduction = change in…
Ages 12 to 14ConceptScience // Ecosystems & Habitats
Evidence for EvolutionDescribe the main types of evidence for evolution: the fossil record (change over time), comparative anatomy (homologous structures), and the geographic…
Ages 12 to 14ConceptScience // Ecosystems & Habitats
Species Distribution & ChangeExplain how environmental change (climate change, habitat loss, pollution) affects the distribution of species, including range shifts, local extinction, and…
Ages 12 to 13ConceptScience // Ecosystems & Habitats
Variation in SpeciesExplain variation within and between species, distinguishing between continuous variation (e.g. height) and discontinuous variation (e.g. blood group), and…
Ages 12 to 13ConceptScience // Ecosystems & Habitats
Biodiversity & ResilienceExplain what biodiversity means, why high biodiversity makes ecosystems more resilient, and describe the ways human activity threatens biodiversity (habitat…
Ages 12 to 14ConceptScience // Ecosystems & Habitats
Toxins Building Up in Food ChainsExplain how organisms affect and are affected by their environment, including the bioaccumulation of toxic materials (e.g. pesticides, heavy metals) through…
Ages 12 to 13ConceptScience // Ecosystems & Habitats
Chromosomes, Genes & DNADescribe the relationship between chromosomes, genes, and DNA in heredity, including the double helix structure of DNA and the historical roles of Watson…
Ages 12 to 13ConceptScience // Ecosystems & Habitats
Genetic MutationExplain genetic mutation as a random change in DNA sequence, describe causes of mutation (e.g. radiation, chemicals, copying errors), and explain that most…
Ages 12 to 14Concept