Bird and Insects Cope With Climate Change (5)
Our planet goes through cycles of extreme heat to extreme cold, and back and forth again. As the cycle progresses, there have been times when 75% or more of species have disappeared in a relatively short period of time. These are called mass extinction events.
During the Cambrian period, which began about 540 million years ago, life exploded into a vast array of forms. Since that time, there have been five events that qualified as mass extinctions, the so-called “Big Five.” They’ve happened on average every 100 million years or so, and are a scientific benchmark to determine whether human beings have created the conditions for a sixth mass extinction. The largest of these events occurred 250 million years ago and wiped out 95% of the species on the planet.
What’s your opinion? Is today’s biodiversity crisis really a sixth mass extinction?
I tend to think so. The Earth is currently experiencing an extinction crisis both on land and in areas covered by water. Previous mass extinction events closely followed climate change triggered by asteroids or volcanic activity, but things are different today. Species are being lost due to a combination of direct and indirect human activities. The destruction and fragmentation of habits, for example, and direct exploitation such as overfishing and hunting. Other factors include invasive species, chemical pollution, and global warming caused by human beings.
I see. It sounds like we need to get our planetary house in order-before it’s too late.
Words-so innocent and powerless as they are, as standing in a dictionary, how potent for food and evil they become in the hands of one knows how to combine them.
