GLOBAL WARMING IS CAUSING EXTINCTION OF SOME LIFE

Noting the prevalent view of species adaptation, environmental scientist, Dana Nuccitelli,  says: [1]

Species evolve through the process of natural selection.[2] The members of the species that are best adapted to threats survive to pass on their genes to the next generation. … [T]his process is a slow one. Humans are causing the climate to change rapidly, in a matter of decades, while big evolutionary changes generally take thousands of years.

In Earth’s history, there have been five catastrophic events where most species weren’t able to adapt fast enough to avoid extinction. These are called Mass Extinction Events. In most cases, these events were triggered by huge volcanic eruptions. Those eruptions pumped loads of particles and carbon dioxide into the atmosphere. The particles blocked sunlight, causing a period of sharp cooling. The carbon dioxide increased the greenhouse effect and caused long-term warming. Most species were unable to adapt to these big climate changes.

5 mass extinctions
(CC) 0, (CC) By-SA, (CC) By-SA 3.0
  • The first mass extinction event happened 445 million years ago, when 86% of species went extinct at the end of the Ordovician Period. Scientists think that this mass extinction was the result of an intense ice age caused by unusual volcanic events, followed by a warm period 1 million years later. Most species weren’t able to adapt to these big climate changes.
  • 360 million years ago, 75% of species went extinct at the end of the Devonian Period. Scientists think that this mass extinction event was also due to a series of relatively rapid environmental and climatic changes.
  • 250 million years ago, about 85% of species went extinct at the end of the Permian Period. This mass extinction event is also known as ‘the Great Dying’ because nearly all marine species went extinct. Scientists think this event was caused by a massive volcanic eruption covering much of modern-day Siberia. The sulfur ash pumped into the atmosphere by the eruption caused global cooling by blocking sunlight, and created acid rain. The carbon dioxide released into the atmosphere from the eruption later caused global warming.
  • Trapped methane, another greenhouse gas, may have been released from the warming oceans, causing even further global warming. The result, 200 million years ago, [was that] 80% of species went extinct at the end of the Triassic Period. Scientists think that this mass extinction event may have also been caused by a series of large volcanic eruptions.
  • 65 million years ago, 76% of species went extinct at the end of the Cretaceous Period. This is when dinosaurs went extinct. This mass extinction event was caused by a combination of volcanic eruptions and a large meteor impact.

Scientists are concerned that we may now be entering the Earth’s sixth mass extinction. Based on the fossil record, [they have determined] it’s normal for about 40 species to go extinct per year. Over the past 1,000 years, the average extinction rate has been 24 times as large as that natural rate. Over the past 500 years, extinctions are happening at least as fast as the rate that triggered the previous 5 mass extinction events. … [M]ass extinction events usually happen slowly, over hundreds of thousands to millions of years. However, if we lose all currently threatened species, we’ll be on a course for a new mass extinction event in just over 500 years.

One myth contends that humans and other species will simply be able to adapt to the Earth’s changing climate, so we have nothing to worry about. This myth employs the fallacy of jumping to unwarranted conclusions. Unfortunately, just because adaptation exists, it doesn’t mean that species can adjust to any new situation–the 5 mass extinctions over the past 450 million years, during which more than three-quarters of the species on Earth went extinct, tell us that species often do not adapt. There is a limit to how fast species can evolve.

Graphic of some of the 40% of species that are at risk of extinction because of global warming
(CC) By-SA 3.0, Biodiversity on Earth: animals, en.wikipedia.org, McZusatz, multiple authors

Humans are changing the Earth’s climate as fast, as or faster than during previous mass extinction events, so fast that species are already struggling to keep up.

Adaption in this case means changing course by transitioning away from fossil fuel. If we do not change course, it will take millions of years for the planet to recover from a human-caused mass extinction event. Fortunately, there is still time to help prevent a huge loss in the Earth’s biodiversity if we do it now by clicking HERE to help adopt the 80% renewable electricity by 2050 initiative.

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