15.00 – 15.10h: Ansgar Büschges
(Dean of Faculty of Mathematics and Natural Sciences, University of Cologne)
Words of Welcome in Honour of Martin Schwarzbach
15.10 – 15.30h: Bettina Adenauer-Bieberstein
(Honorary Consul of Iceland in Cologne)
“Martin Schwarzbach and his special relation to Iceland”
15.30 – 16.30h: Rick Potts
East Africa is the source of much information about the evolution of early human ancestors. A synthesis of East African environmental data suggests that significant events in human origins typically developed during lengthy eras of strong climate fluctuation. Analysis of Earth’s orbital dynamics offers a model of alternating high and low climate variability over the past 5 million years.
This high/low variability model shows that fluctuations between arid and moist climate were important in the evolution of key human adaptations. The origin of the major early human lineages, critical transitions in stone technology, and the main geographic milestones in human origins all appear to coincide with prolonged intervals of intense climate variability. Climate dynamics and resource uncertainty likely shaped the adaptive versatility of our species, expressed by the expansion of mobile technologies, symbolic behavior, social networks, and behavioral diversity. Long climate sequences obtained by drilling in the East African Rift Valley, including near the site of Olorgesailie, Kenya, will test these ideas about the significance of adaptability in the origin of our species.
16.30 – 16.45h: Coffee Break
16.45 – 17.45h: Mark Maslin
Current evidence suggests that all of the major events in hominin evolution have occurred in East Africa. Over the last two decades, there has been intensive work undertaken to understand African palaeoclimate and tectonics in order to put together a coherent picture of how the environment of East Africa has varied in the past. The landscape of East Africa has altered dramatically over the last 10 million years. It has changed from a relatively flat, homogenous region covered with mixed tropical forest, to a varied and heterogeneous environment, with mountains over 4 km high and vegetation ranging from desert to cloud forest.
The progressive rifting of East Africa has also generated numerous lake basins, which are highly sensitive to changes in the local precipitation-evaporation regime. There is now evidence that the rapid oscillation between the presence and absence of deep-water lakes in East Africa were concurrent with major events in hominin evolution. It seems the unusual geology and climate of East Africa created periods of highly variable local climate, which, it has been suggested could have driven hominin speciation, brain expansion and dispersal out of Africa. One example is the significant hominin speciation and brain expansion event at ~1.8 million years ago that seems to have been coeval with the occurrence of highly variable, extensive, deep-water lakes. This complex, climatically very variable setting inspired the pulsed climate variability hypothesis that suggests the long-term drying trend in East Africa was punctuated by episodes of short, alternating periods of extreme humidity and aridity. The fundamental question, however, remains how much did variations in the landscape versus social factors influence the 80% expansion of brain capacity and the dispersal out of Africa at 1.8 million years ago.
17.45h: Get Together (incl. Snacks & Drinks)
Date, Time: 29/04/2016, 15:00 h – 19:00 h