摘要:

AbstractThe story of the Donner Party combines powerful American themes. The beginning of the tale is immersed in the romance of the western frontier and in the American dream of improving life by taking bold steps. The end of the tale, in contrast, is awash in death and cannibalism. No wonder Americans learn the story as children; no Grimm's fairy tale can match it. However, detailed analyses of the patterning of Donner Party deaths suggest that the story is even better read as a piece of biology than as a piece of history. Virtually all aspects of Donner Party mortality can now be explained by our knowledge of the factors that cause differential mortality in human societies. The differential fates of these emigrants show us natural selection in action.

ISSN:1060-1538    

DOI:10.1002/evan.1360020502

出版商:John Wiley&Sons, Inc.    

年代:1993

数据来源: WILEY

摘要:

AbstractDuring their 120 to 165 million years of isolation, the flora and fauna of Madagascar evolved, to a large extent, independently of the African mainland.1In contrast to other oceanic islands, Madagascar is large enough to house the major components of tropical ecosystems, allowing tests of evolutionary hypotheses on the level of complete communities. Taking lemurs, the primates of Madagascar, as an example, evolutionary hypotheses correctly predict the organization of their community structure with respect to ecological correlates. Lemur social systems and their morphological correlates, on the other hand, deviate in some respects from those of other primates. Apparently, lemur social systems are influenced by several selection pressures that are weak or rare in other primates. These include variable activity patterns and avoidance of infanticide. The interspecific variation in lemur social systems therefore offers a unique opportunity for a comprehensive study of the determinants of primate social systems.

ISSN:1060-1538    

DOI:10.1002/evan.1360020503

出版商:John Wiley&Sons, Inc.    

年代:1993

数据来源: WILEY

摘要:

AbstractMany archeological and paleoanthropological sites cannot be dated by well established and common dating techniques such as uranium series (U‐series) or argon‐argon (40Ar/39Ar) because of the lack of materials that are suitable for these techniques. Most sites, however, contain bones and teeth, and the latter can be used to obtain electron spin resonance (ESR) age estimates. The theoretical age range of ESR dating accuracy lies between a few thousand and more than a million years. In practice, continuing uranium accumulation increases the uncertainty of ESR age assessments in such a way that most age assignments beyond 300,000 years are very uncert

ISSN:1060-1538    

DOI:10.1002/evan.1360020504

出版商:John Wiley&Sons, Inc.    

年代:1993

数据来源: WILEY

ISSN:1060-1538    

DOI:10.1002/evan.1360020508

出版商:John Wiley&Sons, Inc.    

年代:1993

数据来源: WILEY

ISSN:1060-1538    

DOI:10.1002/evan.1360020509

出版商:John Wiley&Sons, Inc.    

年代:1993

数据来源: WILEY

ISSN:1060-1538    

DOI:10.1002/evan.1360020501

出版商:John Wiley&Sons, Inc.    

年代:1993

数据来源: WILEY