First light
The universe expands, cools, and begins making the elements.
A field atlas of life on Earth · Est. 1859 / Reconsidered today
All lifeis kin.
Follow 13.8 billion years from first light to the branching abundance of life—and the voyage that taught us how to see the connections.
Enter deep time↓A living encyclopedia of descent with modification
51.331° N0.053° E
Before biologyⅠ
A universe becomes capable of remembering itself.
The history of life occupies only the final fraction of cosmic time. Yet within that fraction, matter learned to copy, vary, compete, cooperate—and evolve.
The scale of becomingDrag or scroll through time →
Earth forms
A restless rocky planet gathers around a young Sun.
Life leaves traces
Microbial ecosystems alter seas, rocks, and atmosphere.
Animal worlds multiply
Complex bodies diversify through Cambrian seas.
Vertebrates meet land
Fins, limbs, lungs, and landscapes enter a new relationship.
Feathers take flight
One dinosaur lineage carries its ancestry into the sky.
After impact
Surviving birds and mammals radiate into emptied ecologies.
Homo sapiens
One young twig learns to read the history of the whole tree.
PL. I
Cambrian Period
Chapter I538.8–485.4 million years ago
Cambrian Period
The sea invents new bodies.
Eyes, armor, grasping limbs, guts, burrows: evolution explores the architecture of animals. The “explosion” was not an instant, but a geologically rapid expansion of forms and ecological relationships.
Field plate
Open folio↗- 01Trilobita
- 02Anomalocaris
- 03Opabinia
- 04Hallucigenia
PL. II
Late Devonian
Chapter II419.2–358.9 million years ago
Late Devonian
The shore becomes a frontier.
Lobe-finned fishes already carried bones homologous to our upper arms, forearms, wrists, and digits. In shallow, oxygen-poor waters, old structures found new uses. Limbs did not appear for a purpose; selection worked with inherited variation.
Field plate
Open folio↗- 01Tiktaalik
- 02Eusthenopteron
- 03Acanthostega
- 04Archaeopteris
PL. III
Late Jurassic
Chapter IIIAround 150 million years ago
Late Jurassic
A dinosaur lineage takes the air.
Birds are not merely descended from dinosaurs: they are living dinosaurs. Feathers preceded powered flight, serving insulation, display, brooding, and balance before natural selection reshaped them for air.
Field plate
Open folio↗- 01Archaeopteryx
- 02Maniraptora
- 03Pennaraptora
- 04Aves
The engineⅡ
Evolution has no destination.
Populations change because individuals differ, some differences are inherited, and survival and reproduction are unequal. Add time, and small biases can redraw the living world.
Variation
Different by natureMutation, recombination, development, and environment make individuals unlike one another.
✣Inheritance
Information continuesSome differences pass between generations through genes and other biological systems.
✣Selection
Consequences differTraits that affect reproductive success can become more or less common in a population.
✣Deep time
The patient multiplierSelection, drift, migration, and isolation accumulate across immense spans of generations.
✣Common descentⅢ
Touch a branch. Find a relative.
This simplified tree shows relationships, not a march toward humans. Every fork represents a shared ancestral population; every tip is a surviving experiment.
1831–1836 · HMS Beagle
The voyage did not give Darwin an answer. It taught him how to ask.
Geology stretched time. Fossils made extinction tangible. Islands turned variation into geography. Back in England, specimens, breeders, books, and two decades of thought connected the evidence.LOG OF H.M.S. BEAGLE1831—1836
Santiago, Cape Verde
Raised shells high above the sea make Earth’s slow movement visible.
Bahia, Brazil
Tropical abundance overwhelms the categories of a young collector.
Punta Alta, Argentina
Giant extinct mammals resemble smaller living South American forms.
The Andes, Chile
Marine fossils in mountains bind deep time to planetary change.
Galápagos Islands
Related forms differ from island to island: place and descent begin to converge.
England
The voyage ends. The long work of explanation begins.
The cabinetⅣ
Field notes & long reads
Evidence, mechanisms, and journeys—maintained as an Astro content collection for a growing bilingual encyclopedia.
01
Mechanism · 11 min read
Open folio ↗02The mechanism of natural selection
How variation becomes adaptation without foresight, need, or design.
Geological time · 13 min read
Open folio ↗03How to read deep time
The rock record is incomplete, but its fragments agree with one another.
History of science · 15 min read
Open folio ↗How Darwin connected the evidence
The Beagle supplied observations; comparison and twenty years of work made the theory.