Climate change catalyst
Evolution is driven by natural selection of the individuals best adapted to the environment that it is a part of, and this happens both within and between different species, slowly over time giving rise to new species. In times of rapid environmental or climatic changes however, the pressures for natural election become extreme and those organisms able to adapt to the new conditions will survive, while those that cannot die out. When a whole species fails to adapt it becomes extinct.
Evolution is a slow process, but at five notable times in the past the conditions on Earth changed rapidly enough that evolution struggled to keep up, resulting in mass extinctions, at times up to 95% of the life previously present on the planet. This has profound implications for today's world - the Anthropocene - where humanity is causing rapid changes in Earth systems and climate which has immediate effects and also longer term effects, that combined with other human factors has arguably plunged Earth into it's sixth mass extinction which is occurring today.
Evolution is a slow process, but at five notable times in the past the conditions on Earth changed rapidly enough that evolution struggled to keep up, resulting in mass extinctions, at times up to 95% of the life previously present on the planet. This has profound implications for today's world - the Anthropocene - where humanity is causing rapid changes in Earth systems and climate which has immediate effects and also longer term effects, that combined with other human factors has arguably plunged Earth into it's sixth mass extinction which is occurring today.
“Evolutionary adaptation can be rapid and potentially help species counter stressful conditions or realize ecological opportunities arising from climate change. The challenges are to understand when evolution will occur and to identify potential evolutionary winners as well as losers, such as species lacking adaptive capacity living near physiological limits.”
Climate change and evolutionary adaptation. Ary A. Hoffmann1 & Carla M. Sgro`2 [1]
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Mass extinctions and evolution
With the current challenges facing life globally from climate change and habitat destruction and fragmentation, it is a relevant question to ask: what effect will the current and ongoing mass extinction have on life on Earth?
Climate change in the past has culminated with a mass extinction, with "the great dying" of the Permian - Triassic extinction event losing 75% of the life that had existed before.
However this creates a kind of gap where species that have an advantage in the new conditions over the previously dominant species highly adapted for the old ones, so where previously they were at a disadvantage now they can fill new ecological niches and cause evolutionary radiation, defined as "...an increase in taxonomic diversity or morphological disparity..."
Climate change in the past has culminated with a mass extinction, with "the great dying" of the Permian - Triassic extinction event losing 75% of the life that had existed before.
However this creates a kind of gap where species that have an advantage in the new conditions over the previously dominant species highly adapted for the old ones, so where previously they were at a disadvantage now they can fill new ecological niches and cause evolutionary radiation, defined as "...an increase in taxonomic diversity or morphological disparity..."
References:
[1] Climate change and evolutionary adaptation. Ary A. Hoffmann1 & Carla M. Sgro, National Geographic
[1] Climate change and evolutionary adaptation. Ary A. Hoffmann1 & Carla M. Sgro, National Geographic