Climate-forced evolution and man-forced environmental change

Climate-forced evolution of early man and large African mammals during the Pliocene-Quaternary transition is discussed. Marine records of climatic change in Africa north of the equator during the last 5 million years show that environmental conditions became much drier causing a substantial increase of the Sahara and loss of wet forest. Examples of climate-forced and tectonism-forced environmental changes in northern South America are shown. Man-forced environmental change since at least the last 12,000 years is illustrated with examples from Australia, Guatemala, Colombia and Brazil. On the long time scale human impact on the environment appears mure difficult to identify than climate impact on the environment and even climate impact on evolution.