[Editor: An article from the “Science and Nature “column (by “Achernar Major”) published in The Brisbane Courier, 30 October 1926.]
A survey of Australia’s past.
Australia is the smallest, but most peculiar of the continents. Everything in it strikes the naturalist as strange and archaic in character. Its vegetation, comprising tree ferns, cycads, and araucarias, &c., recalls that of the Secondary era, during which reptiles were the dominant creatures of the earth. In the seas surrounding it are found shell fish such as Trigonia, long extinct in other parts of the globe, and the Nautili, of Jurassic and Cretaceous seas. In its rivers still lives the lung fish, Ceratodus, that curious amphibious fish which was first discovered in the Triassic rocks of Europe. The dry land is peopled by a peculiar mammalian fauna, which includes the Monotremes (platypus and echidna), belonging to a primitive and still reptilian type of mammal; and it is almost wholly composed of forms remaining at the marsupial stage. This fauna forms a legacy from the Secondary era, which, nevertheless, has been considerably enlarged and diversified. The indigenous human populations, likewise, belong to one of the most primitive of modern races.
The majority of these general features of Australia may be explained by its geological and ancient geographical history. Peering into the past the earliest knowable association of Australia with other parts of the globe seems to be that when it was united to a vast Antarctic continent, including South Africa, Madagascar, India, and part of South America — a continent known to geologists as Gondwanaland. The latter in some way began to break up, and Australia became completely isolated from the mass. It seems that during Cretaceous times (the end of the Secondary era) there may have been a temporary communication with Asia through the lands of the Malay Archipelago, but after the end of Cretaceous times, or at the commencement of the Tertiary era, Australia became an independent and isolated entity, possessing much its present form.
Thus these have remained, imprisoned on an immense island, the flora and fauna which were then dominant throughout the world. As this isolation seems to have lasted, more or less completely, up to our own time, the organised life of Australia has been compelled to continue its own evolution in its own area, borrowing very little from the rest of the world, and gradually assuming its present aspect. This independent evolution, carried on in a very special direction, has produced the extraordinary diversity of marsupial mammals, some of which, not so long ago, attained to gigantic size. It is very difficult to explain the settlement of Australia by man, who could only have been one of the latest comers, unless we believe that Australia is the place of origin of our species — a supposition which seems hardly admissible. We leave this history for treatment in next week’s notes.
Source:
The Brisbane Courier (Brisbane, Qld.), 30 October 1926, p. 16
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