Human overkill, as a result, became the difference between extinction of animal species and survival. But against humans with spears the defense pattern was nearly useless. Such a defense arrangement worked well against wolves, even large dire wolves and saber tooth cats. Bison, particularly ancient straight-horn bison, when confronted with danger as from wolves, for example, tended to cluster with bulls or large females on the outside facing the threat. Many animals had no significant defense system to use against humans, creatures with whom they had not long been in contact. Noting that end of Ice Age extinctions are not evident in the plant kingdom, they suggest that overhunting by humans represented a devastating impact on animal populations already in decline. Scientists who maintain that humans played a significant role in the Pleistocene extinctions go further. They could move, certainly, but their grazing and foraging zones became smaller and spread apart over greater distances. The largest species, particularly sensitive to climatic change, had no such chance. Smaller mammals could adjust and move into empty ecological niches.
The tundra of northern Europe, Asia and North America shrunk, also adversely affecting large mammals. On the Great Plains, for example, tall, coarse grass savannahs that supported large mammals disappeared in favor of short grasses and spreading forest lands. Some of the most passionate, and most popular, arguments suggest overhunting by early humans, but the majority of explanations cite changing climate and weather patterns at the end of the last great Ice Age - the Wurm-Weichsel-Wisconsin glaciation.Īs glaciers retreated at the end of the Ice Age, the climate and weather patterns warmed, ecosystems changed, vegetation types shifted. A few theories describe such influences as disease epidemics, accidental change of sex ratios, astronomical agents, the beginning of agriculture and others. Reasons for the great die-off at the Pleistocene-Holocene (modern epoch) boundary remain something of a puzzle. In South America, large animal species, such as tapirs and giant rodents, suffered an 80 percent loss, and in North America, including the Southern Great Plains and the Llano Estacado, the percentage of loss for large animal species may have reached beyond 66 percent. Perhaps 86 percent of the large animals of Australia became extinct, many of them even before 15,000 years ago. In Europe, during the late Pleistocene die-off ,the death of species was relatively small, but elsewhere around the globe the extinctions were massive. Large numbers of animal species perished. The Pleistocene (or Ice Age) extinctions began between 15,000 to 10,000 years ago during the last years of the late Pleistocene epoch. The most famous mass extinction occurred about 65 or 66 million years ago at the Cretaceous-Tertiary (K-T) boundary when a giant meteor or comet struck the planet, triggering a catastrophic crisis that ended the age of dinosaurs. The worst such extinction event appeared 250 million years ago at the boundary between the Permian and Triassic periods when 95 percent of all land animals died - and seemingly all at once. Mass extinctions of animal, plant, and aquatic life have occurred on Earth more than a dozen times since life began some four billion years ago. The essay this week looks at the massive extinction of large mammals on the Southern Great Plains more than 10,000 years ago. Infusing trend-forward graphics and prints into stylish silhouettes is boohooMAN’s goal and they do it well.Editor’s note: Caprock Chronicles is written or edited by Paul Carlson, emeritus professor of history at Texas Tech. Like ASOS,boohooMAN offers fashion for the average size and the big & tall guy, all at a budget-friendly price point. Why don’t we dive in to these ASOS alternatives so you have many more options to choose from when shopping for clothes. There are tons of stores like ASOS that have a similar vibe, but with slight variations (and perhaps those variations are more your style anyway). Sure, the target demographic of ASOS skews a bit younger, but even if you’re in your 30s and 40s, you’re bound to find stuff that works for your style, especially if you’re young at heart and open to slightly trendier options mixed in with your classics and basics. Does ASOS have brick-and-mortar stores?.
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