Roos in the news
A couple of weeks ago a University of Wollongong media release made this announcement concerning fossil discoveries made in 2002:
In 2002, a team of cavers exploring the vast, treeless Nullarbor Plain of southern Australia made what some paleontologists described as the “find of the century” — a dozen skeletons of the extinct marsupial ‘lion', Thylacoleo, as well as the bones of giant wombats, short-faced kangaroos and thylacines.
The finds illustrate a truth but dimly perceived by most of us, including myself until relatively recently — our fair planet has played host to a staggering array of creatures over the course of millions of years. Sure, we all know about dinosaurs, and possibly about bizarre fish and ichthyosaurs that once plied long-gone shallow seas. But few are aware that dinosaurs died out over sixty million years ago and that since that time all kinds of fascinating mammals, birds and reptiles have lived, thrived, then vanished. (Indeed, many mammals lived side by side with dinosaurs over many millions of years.) The caves on the Nullarbor — dubbed the Thylacoleo Caves after the scientific name of a species of marsupial “lion” found there — harbor the remains of 69 different species of marsupial lions, kangaroos and wombats, birds and reptiles that lived in this barren wilderness between 400,000 and 800,000 years ago.
Many of the fossils discovered were of
species known to scientists for some time, but quite a few were new, including eight of the 23 species of kangaroos. (Ironically, two of the kangaroo species were evidently tree dwellers — the Nullarbor Plains today are virtually treeless! Why trees once abounded where now they are almost unknown remains somewhat of a mystery, since all the evidence shows that the climate was much the same then as it is now.) This fact yet again raises a most intriguing thought: if one cave system from a moment in time brings many new species to light, how many other species have existed over time about which we are utterly ignorant? The fossil evidence suggests that different assemblages of creatures thrived at different times over the past 65 million years (the Cenozoic Era). Not just in Australia but all over the world. North American deposits have yielded enormous numbers of camel, rhino, horse, mastodons, giant sloth, borhyaena, marsupial, and so on. But what have they not revealed? What new discoveries lie ahead?
Even if not another single species is ever discovered, what we already know about blows the mind. The evidence is in and is clear: Our planet has been constantly changing over millions of years. The stage scenery has been constantly refreshed and the parade of actors has turned over as regularly as on a soap, though the basic theme can remain fairly static for millions of years (most of Australia's extinct creatures — but certainly not all — belonged to families extant today.) And where have these creatures come from? From the infinitely creative mind of God, of course.