The Pale Blue Dot

I’m not sure if you have been following any of the Charles Darwin programs on the tv recently but I watch the series of 3 called “Darwin’s dangerous idea”. The final one was on last Thursday and I managed to watch it over the weekend. I was amazed at how much stuff was in there that I didn’t know, especially as I watch and read everything I see regarding these things. This is a short blog highlighting some bits mentioned in this last program.

I knew that there had been 5 mass extinctions in the past where between 65 and 95% of all species had been killed off in quite a short space of time. Like when the dinosaurs were killed off 65 million years ago by the comet or meteor that struck the earth giving us mammals a chance. I had also heard it said that we are currently at the beginning of the 6th mass extinction but just hadn’t grasped the scale of it. You occasionally hear of another species disappearing or only a few left and we all know that lots are endangered but I didn’t realize that 27000 species were going extinct every year. That’s species, not animals; 27000 entire species are dying every year, never to be seen again directly due to us. I hadn’t grasped the scale or significance of this, especially with the inter-relationships of different species in their ecosystems. This is serious trouble and I can’t see how we can do much to stop it or even slow it down. It seems to me if it goes on unchecked it is only a matter of time before the whole system breaks down.

It sort of reminds me of James Lovelock’s book about Gaia which is also mentioned in the program. His neighbour was William Golding, the guy that wrote “Lord of the Flies” and whilst they were out for a walk one day he came up with the idea of Gaia who was the Greek Goddess of the Earth. In this book, the Earth acts like a giant organism that, to a large extent, self regulates and keeps things at a status quo. Well worth reading. The program also mentioned that Darwin wrote the very first paper on Coral reefs. These are interesting as they are like the canary of the mining world. At the first sign of trouble they die out first going white in what is called Coral bleaching. Coral is also under threat.

Also mentioned was the rise and fall of the Peppered Moth during the industrial revolution. Another great classic, written by James W Tutt where the light version of this moth thrived before the onset of smog and the few dark versions thrived after to become the most common where 98% were black during this period. This story is regularly repeated when talking about mankind’s effect on evolution. David will be proud of me for remembering.

The biggest surprise for me was that Darwin’s last book with the catchy title of, “The formation of vegetable mould by the action of worms (with observations on their habits)” became a best seller during his lifetime, far outselling “On the Origin of Species”.

I leave you with a quote from Carl Sagan’s classic, “The pale Blue Dot” inspired by an early space photograph taken of the planet Earth by Voyager 1 from a distance of nearly seven billion kilometres (4 billion miles) as part of the Solar System family portrait.


Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader", every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.

Sagan, C. (1994). Pale Blue Dot: A Vision of the Human Future in Space. Random House, New York.