The Quaternary Extinction & The Evolution of Modern Mammals

Ice Age MegaFauna

Ice Age MegaFauna

As concern continues to grow over climate change and the rapidly altering ecosystems around the globe, examining the past provides unique insight into the cyclical patterns of nature. Massive extinctions and catastrophic changes in climate have been the catalyst for a number of massive ecological changes. Massive epoch ending extinctions pave the way for new organisms to evolve and create a new environment for adaptation to thrive.

The most recent and mysterious is the Quaternary extinction event, which occurred 13,000 years ago. Also referred to as the Pleistocene extinction, this event saw the extinction of numerous megafauna species. Common megafauna (which consist of species over 100 pounds) included several species of wooly mammoth, giant hippos, saber-toothed tigers, and a variety of other large mammals that were common throughout the North American continent.

The driving cause of the Pleistocene extinction remains largely unknown. Such a massive extinction of large animals points many to believe the cause was a cataclysmic event. Due to the multiple glacial advances and withdrawals many scientists believe this rapid change in the ice age may explain such massive extinctions. Massive melting and tumultuous climate conditions could have quickly altered vegetation, forcing these larger animals to starve or migrate.

The documented evidence of early human beings make this period unique compared to other ancient extinctions. Theories of human overhunting have emerged as a potential cause for the massive extinction of these megafauna but similar to the discussion of climate change in contemporary discussion, the impact of human interaction may be severely overstated.

As more research on the changing climate of Earth emerges through geology and paleoclimatology, the ancient events of Earth’s biological past begin to emerge. This notable epochs mark the distinct developmental branches and ushers in new environmental conditions that force evolutionary adaptations. Whether from hunting or catastrophic climate changes, the large megafauna of the Quaternary age were unable to adapt to the changing environmental conditions.

Sources:

“Was a hyperdisease responsible for the late Pleistocene megafaunal extinction?”  Kathleen Lyons, Felisa A. Smith, Peter Wagner, Ethan P. White, and James H. Brown. Ecology Letters, (2004)

Images:
“Ice age fauna of northern Spain” by  Mauricio Antón