PALYNOLOGY AND PLEISTOCENE ECOLOGY 



G. Erdtman 



Palynological Laboratory, Stockholm-Solna. Sweden 



The broad outline of Post-glacial plant development was emphasized by 

 Andersson (1909) more than 50 years ago. His conclusions were based mainly 

 on the occurrence of megascopic fossils in Scandinavian and Finnish peat 

 deposits. It was, however, von Post (1918) who, in the second decade of the 

 present century, introduced pollen statistics as a new botanical and geological 

 research method, thereby inaugurating the present epoch of pan-global 

 research into vegetational and climatical history. The main stages of the 

 development, which can be condensed and vividly portrayed by following the 

 story of "cryocrats", "protocrats", etc., have been elucidated by von Post 

 {loc. cit.) and those who have followed in his footsteps (e.g. Firbas, 1949, 

 1952; Iversen, 1958). 



Statocrats. Statocrats, as here defined (Greek statos = stationary, kratos = 

 power), live in stable environments. In Quaternary climatic cycles — from an 

 Ice Age to an Interglacial period to a new Ice Age and so forth — the first 

 statocratic biota are cryocrats (Greek kryos = ice), i.e. elements that can 

 live under the severe conditions of an Ice Age. They are gradually replaced 

 by protocratic biota (Greek protos = first) which characterize the climatic 

 amelioration (after the Ice Age). These, in turn, are succeeded by the meso- 

 crats (Greek mesos = middle) of the Interglacial or Post-glacial Chmatic 

 Optimum. Eventually telocrats (Greek telos = end) close the circle, forming 

 a connecting link between the mesocrats and the cryocrats of a new Ice Age 

 (cf. Iversen, 1958). 



Apocrats. Apocrats, as here defined (Greek apo = back, away), do not 

 live in stable environments. Apocrats are opportunists, kinetophilous elements 

 to which lack of competition generally means more than climatic and edaphic 

 conditions. Thus granted freedom from competition, they can appear at 

 practically any time, be it during an Ice Age or a Climatic Optimum. They 

 invade virgin soil uncovered by a retreating glacier, the sudden drainage of 

 an ice-dammed lake, etc. They hkewise spread into areas emerging from the 

 sea as the result of eustatic sinking of the Ocean level or isostatic upheaval of 

 land. They also enter areas where a temporary freedom from competition 

 accompanies the upsetting of the natural balance by axes, plows, bulldozers, 

 etc., in fields and forests, along liighways and railroads, in the outskirts of 

 villages and towns, etc. Intermittent changes induced by volcanic activity or 



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