The Blog

A library of stories and sources

From early cities and scripts to beliefs, science, and contested history. Pick a subject, read a guide, and open the material behind it.

Every guide links its sources. We mark what comes from a surviving object, what belongs to a tradition, and what remains a hypothesis.

9 of 96 source guides

Bolivia and Tanzania; comparative global context Present-day samples informing a prehistoric migration model

Did gut microbes travel with us? A genomic model of deep migration

Gut microbes may carry traces of ancient human movement. Researchers reconstructed a possible route with a model; nobody observed that journey directly.

Global Hypotheses about deep prehistory

How far back can language comparison reach?

Proposed ancestors of very old language families reach beyond surviving texts. Where can comparison still test a claim, and where does it become a hypothesis?

Damascus and Frombork 14th–16th centuries CE

Copernicus and Ibn al-Shatir: how close are their Mercury models?

Two models of Mercury’s movement look strikingly alike. Which matches suggest knowledge was passed on, and which leave its route unproven?

Damascus, the Veneto, Cracow, Uppsala 14th–16th centuries CE

From Maragha to Copernicus: tracing a transmission claim

Copernicus’s planetary models resemble earlier work by astronomers in the Islamic world. Which steps in the possible transmission are documented, and which are missing?

Cracow, Padua, and Uppsala 14th–16th centuries CE

Bianchini’s tables in Copernicus’s hand: what is proven?

Copernicus copied planetary latitude tables in his own hand. It is a strong find, but does not by itself settle every question about how he used them.

Maragha, Constantinople, and the Italian Renaissance 13th–16th centuries CE

The Tusi couple in Greek: why a shared error matters

A Greek text preserves a Persian Moon model and repeats a numerical error. That shared mistake is stronger evidence of a textual link than a similar drawing.

Damascus and Oxford c. 1366 CE and after

Ibn al-Shatir: which manuscript preserves the relevant theory?

His fourteenth-century planetary theory survives in several manuscripts. His separate work on the astrolabe does not alone prove that his Mercury model reached Copernicus.

Africa Deep human population history; study 2023

Human origins: why does the model include several groups?

A genetic model describes connected ancestral groups with gene flow between them. It is a testable proposal, not a story about one isolated population.

Human populations worldwide Present-day genomic variation

Human genomes: what do we share and where do we differ?

Most human DNA is shared. A research institute’s introduction helps explain differences without turning genetic comparison into a label for a person.