“The Sixth Extinction: An Unnatural History”, by Elizabeth Kolbert (Plus a Brief Description of the Five Extinctions)

Cover via Amazon

Today I was looking around for new books that are worth reading. That’s how I found “The Sixth Extinction: An Unnatural History”. As I was looking at the description, I quickly became both excited and fascinated about the topic. 

So, What is This Book About?

As the title suggests, this book is attempting to give an account of an extinction that is taking place right before our eyes. Along its history, the Earth has seen as many as five mass extinctions.  The sad truth is that another one seems to be under works. In the past, circumstances such as drastic climate changes, and possibly even a hit by a meteorite. For this sixth extinction, however, the reason is us. This is the argument put forward in this book: that we are the cause of  another mass destruction of lives.

Through this book, Elizabeth Kolbert is making her readers reconsider the concept of humanity. When what we leave behind is destruction and death, are we as good as we think we are? The answer, of course, is no. But in order to come to that answer, we must first be convinced by the implication of the question. Are we indeed the cause of the sixth extinction? That’s what the book is attempting to convince us of. If it manages to reach its goal, then it forces its readers to reconsider the essence of human nature.

The Five Extinctions

I plan on reading this book at some point in the future. But even for those who won’t, knowing about the past five extinctions can be a useful piece of knowledge. So let’s find out what they were:

1) Ordovician-Silurian Mass Extinction

This extinction took place 443 million years ago, at the end of the Ordovician period, spilling into the beginning of the Silurian period. Since at that time, most life was present in the sea, it can easily be concluded that losses were in the form of sea creatures. It is believed that as much as 85% of the total life in the waters was wiped out. Though it can’t be said with certainty, scientists believe that an ice age was the culprit here. The freezing of the waters would have had a huge effect on the lives in them.

2) Late Devonian mass extinction

Having occurred 359 million years ago, this mass destruction took away 75% of the life on Earth. Creatures in shallow waters were the ones affected the worst, because the sea bed lost oxygen. Because of this, bacteria were the only ones who were able to survive there. Possible causes for these events include impacts by asteroids and climate change.

3) Permian Mass Extinction

Also known as the Great Dying, this extinction wiped out a staggering 96% of all the living things on Earth. This occurred 248 million years ago, and affected, once again, mostly sea creatures. Insects also had to suffer, as the Permian extinction was the only one that effected them in mass. There are a few possible causes proposed for this event, such as drop in the levels of oxygen and, of course, the ever loved asteroid impact.

4) Triassic-Jurassic Mass Extinction

As with the other extinction, the Triassic-Jurassic one had up to three separate stages. Having taken place 200 million years ago, this destruction was responsible for the death of 50% of lives. Sea creatures and reptiles, and amphibians are among the ones affected. Once again, possible causes are a drastic change in climate and an asteroid.

5) Cretaceous-Tertiary Mass Extinction

The most well-known extinction, the Cretaceous-Tertiary event was when the dinosaurs met their end. Having happened 65 million years ago, this destruction also took the lives of other creatures. Many groups of animals started to decline in numbers before this event. Scientists believe it might be because of a change in climate that was followed by a fall in the level of the sea. The famed impact of the asteroid came as the last drop that ended the dinosaurs.

Those are the five extinctions that have happened in the past. Let’s see if the book manages to convince that a sixth one is occurring as we speak.