Mammals
The fossil record shows that there have been mammals from about 225 million years ago. At the time of the last extinction, around 65 million years ago, which wiped out 90% of the species living at that time, including the dinosaurs, some of those mammals survived. The survivors were small, some no longer than a few centimetres. They survived by means of burrowing underground, to escape the effects of an Ice Age, and because their food needs were small. When the planet reverted to something like normal temperatures, they were able to thrive and eventually evolve into bigger animals, including humans.
Had the dinosaurs continued their existence, one wonders whether they could have survived in the long term. Riley Black (2010) believes that had the non-avian dinosaurs not been wiped out 65 million years ago, our species of mammal would probably never have existed.
Humans
Homo sapiens (humans as we know them) evolved something over 200,000 years ago. Since then they have become the most intelligent creatures that have ever lived. That fact has certainly benefited their own race. They are able to use tools, to keep themselves warm and to foster a lifestyle that most of them desire. What though, of the point of view of the Planet, defined in our introduction as all life, from single celled organisms to complex vegetation and animal life? Sadly they have not fared so well, especially in the last hundred years or so. We have seen that numbers of insects and birds have declined drastically, largely through the use of insecticide and loss of habitat. Numbers of trees show a constant decline. Our fellow mammals, too, have suffered a similar reduction of numbers, unless they are mammals that are useful to humans.
They have polluted the earth and oceans with plastic, and degraded air quality with emissions of sulphur dioxide, carbon dioxide and ammonia. They have contributed to rapid global warming with emissions of carbon dioxide and ozone. To their credit, they are aware of the problem, and trying to reduce it.
It is not that our species is particularly immoral. All species care about their own survival exclusively. The difference is due to two major factors.
A: Their sheer numbers of humans. Human population is growing at what some would regard as an alarming rate
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B the intelligence of humans, which gives them the ability to adapt the Planet for their own benefit
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Both of these factors have led to declining habit of other species, especially the first. Around 1804, the world population reached 1 billion people. In 1927, it reached 2 billion. And then, the world population really took off. In the following 84 years, according to the periodical, The World Counts, the world population grew by 5 billion people reaching 7 billion in 2011. By 2023, world population reached 8 billion people.
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Of course, It is not simply the number of people that determines the impact of the planet. It is how much we consume and how much waste we produce.
For all of recorded history, a growing population has been accompanied by economic growth - and usually per capita growth as well. When the world population doubled in the 46 years between 1971 and 2017, the world economy more than quadrupled from $19.9 to $80.1 trillion (in constant prices). In about the same period from 1970 and 2010, human consumption of Earth's natural resources tripled.
The United Nations (UN News, 11th July, 2024) predicts that it will start to decline in the mid 2080s. It is unlikely, however, that economic growth will. Perhaps then, that is little comfort to other species whose habitat is being destroyed by humans.
There is no doubt then, that humans have had a huge impact on the planet, not least because of the waste products that we leave behind us.
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Home - click here
The Planet's Point of View - click here
The Beginnings of Life on Earth - click here
The First Big Advance - Cyanobacteria, click here
Fabulous Fungi - click here
Vegetation - click here
Insects - click here
Earthworms and Birds - click here
Water based life - click here
The Calculus - click here
