Darwin’s Dilemma, the mystery of the Cambrian Explosion, refers to a period of time during which a diverse range of animals suddenly appear in the fossil record around 500 million years ago. Darwin described it as “inexplicable,” but held onto hope that future scientists would figure it out.
Creationists have often leapt onto this particular detail as evidence against evolution. A study published this September by Australian scientists claims to have discovered an explanation for the events, often called “Evolution’s Big Bang.” The scientists used advanced mathematical modeling and a detailed analysis of the fossil record to reason that a slightly faster rate of evolution at the time would be enough to account for the apparently sudden appearance (sudden, in geological terms, meaning over tens of millions of years). People had previously believed the rate of evolution required was much faster. The necessary rate they calculated is “perfectly consistent with Darwin’s theory of evolution,” according to the study.