Intercontinental Academia - Talk mediated by Vera Imperatriz Fonseca with Tiago Quental and Luiz Gylvan Meira Filho

Earth's time and the Anthropocene. Tiago Quental - "The dynamics and drivers of biodiversity in geological time" The history of biodiversity is characterized by a recurrent extinction of species and by a continual replacement of different branches in the tree of life. This replacement dynamics is ultimately determined by changes in speciation and extinction rates. The fossil record offers an unprecedented opportunity to understand the deep time history of biodiversity because it directly preserves this unfolding dynamics. Quental presented how we can use the fossil record of mammals to discuss the history of biodiversity and the potential factors that might drive changes in speciation and extinction rates at a geological time scale. Luiz Gylvan Meira Filho - "Time scales of and climate change" Climate is defined as the statistics of the variables that describe the instantaneous state of the climate system (atmosphere, oceans and biosphere). The use of proxy variables allows us to retrace the history of the main climate variables as far back as 70 million years before present. A summary of our present knowledge were presented, showing variability of climate in all time scales.