The Victorian naturalist . Cenzoic fossil marsupial sites in Victoria: a progress report BY Thomas H. V. Rich* Introduction The history of Australias uniquemammals and birds begins with a fewfeathers and fleas found at Koonwarrain deposits of early Cretaceous age,about ( = millionyears Before Present) (Waldman,1971). It is thought that the fleas couldonly have hved as ectoparasites ofmammals; hence mammals are thoughtto have been present by this time. From then until about the beginningof the Miocene, approximately , the only record of thesegroups are penguins and
The Victorian naturalist . Cenzoic fossil marsupial sites in Victoria: a progress report BY Thomas H. V. Rich* Introduction The history of Australias uniquemammals and birds begins with a fewfeathers and fleas found at Koonwarrain deposits of early Cretaceous age,about ( = millionyears Before Present) (Waldman,1971). It is thought that the fleas couldonly have hved as ectoparasites ofmammals; hence mammals are thoughtto have been present by this time. From then until about the beginningof the Miocene, approximately , the only record of thesegroups are penguins and cetacean re-mains from a few areas, plus somerare enigmatic traces of what couldbe land birds. Until the beginning ofthe Miocene, therefore, the fossil re-cord is virtually mute about even themost general aspects of the evolutionof terrestrial mammals and birds inAustralia. However, in at least a pre-liminary fashion based on the fossilrecord, it is now possible to chroniclethe evolutionary events after 20 ? Lancefield. Fig. 1. Five fossil marsupial sites in Vic-toria that are currently being studied. that affected the higher ter-restrial vertebrates of AustraHa. That this comparatively detailedhistory of land mammals and birdscan be constructed only for the lastone-sixth or less of the time thesegroups have been in Australia, meansthat much remains to be done byvertebrate palaeontologists to shedlight on the evolutionary events thatoccurred there. By 20 all the major groupsof marsupials and birds had differen-tiated. Therefore, what the fossil evi-dence can now shed Hght on are thephyletic relationships within some ofthe groups best represented in thefossil record. Questions of a broadernature concerning relationships receivelittle useful information from fossilevidence simply because the events ofinterest took place long before therecord begins. Other major questions that a de-tailed understanding of this earlierhistory could throw light upon (were itavaila
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Keywords: ., bookcentury1800, bookdec, booksubjectnaturalhistory, bookyear1884
