The Pacific Northwest is a veritable garden with a rich tepestry of geologic changes, dramatic and varied landscapes, and an intersection of ancient biomes. Many cultures and animals have been a part of this history since it was part of Pangea, a uni-continent that bubbled apart across the globe over the last 2 to 300 million years. Much of what we know, or thought we knew, has largely remained unchanged outside some rare and fortunate chance discoveries, although the last few decades have been illuminating, so we are going to put a succint picture together for this small portion of the planet.
A quick search of continental drift shows us how the tectonic plates have drifted apart and together many times, slowing down about the Triassic period to about where we now sit. Even more recently, particular to our Pacific Northwest area, is the Cascade Episode, where the Juan de Fuca plate met the western edge of the North American plate, diving underneath and buckling the land, eventually forming the Cascades over the last 6 million years or so. It was during the times of connection and isolation, creating what is known as "the Wallace line" around the world, showing out this tectonic activity by the fauna difference along particular invisible barriers, while also both migrating and evolving on the cusp of the Holocene. It was this line that pointed science to earlier mechanisms at play than simple co-location (see also biogeology for this intriguing phenomenon, which shall not be discussed here).
There are ample fossils to indicate the megafauna that inhabited the North American Continent, and that show we sit now on what used to be multiple plates, which is why the continental divide is so different on each side (they used to be halfway around the world from each other) and why the whole biomes are so dispirate. In particular, the PNW contains five different belts! The area boasted large beasts such as sabre-tooth and scimitar-tooth cats, dire wolves (that appear to be genetically related to jackals not wolves), mammoths and mastodons, American Lions, American Hyenas, giant sloths, and a terrifying creature called a short-nosed bear whose fossils were found near tule locations. :arge amounts of prey and huge predators were crossing the Bering, the Cascades were rising, and a new species of ungulate arrived on the fossil scene -- white tail deer. The same we have today, just 5 million years ago.
In his book, Deer of the World: Their Evolution, Behavior and Ecology, by Valerius Geist, the author explains that while other modern ungulates here in North America are measured in the tens of thousands of years where the fossil record goes, while there is a sample in Florida of what appears to be our White Tail deer that is 5 million years old, and they have flourished even in places of "ecological havoc" wrought by man. Geist claims these marvels of nature have used their This is a story about an opportunistic way of life, a set of skills well
mastered by white-tailed deer,” wrote Geist. “It has virtually evaded
evolution, and that is supreme success. After all, evolution is de facto
proof of incompetence, of difficulties mastered by only a fraction of
the population after all normal means of epigenetic adjustment have
failed, and of extinction barely missed. The whitetail was very good at
avoiding extinction.”
We know someone has been watching now for over 50,000 years
It somehow outran and outlived the 15 predators we know of that were larger than wolves, and left few intermediary fossils since the Paleolithic. The author suggests its numbers were somehow perfectly maintained to have survived to present day. Is it really a singular master of environmental adaptation, remaining alive and unchanged? While our ancestors were busily adjusting to bipedalism, and changing drastically into dozens of species, which we have tracked and traced over the planet? While 38 of its coexisting fauna succombed to the rigors of the Ice Age and other smaller mini- ice ages since then? Was it, as is claimed, lucky to be "born perfect?" Pulled a blackjack on its first hand at the table?
Or did it have help?
Part 2 coming soon
No comments:
Post a Comment