The impact of climate change on biodiversity in the tropics has emerged as a key issue in global change research. The consequences for tropical biota of even small rises in temperature, shifts in moisture regimes and changing magnitude of major disturbance events such as floods, drought and fire are likely to be profound. This is particularly critical for many threatened species as massive habitat shifts under increasing pressure from human activity may lead to biodiversity loss. Human populations in the tropics are also vulnerable due to the extreme poverty of many tropical nations and their reliance upon agricultural systems that are heavily dependent on rainfall. Despite the threats to human populations and biodiversity there remains a high level of uncertainty around estimates for the magnitude, direction and pace of future tropical climate change. Examining past records of climate and biodiversity change in the tropics may provide a key to understanding future responses of biota to climate change.