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The perspective shift of evolution

Image: Pixabay

I just wanted to share something that I’ve recently been delving into a bit more thanks to my studies- namely, the age of the Earth people commonly accepted before the theory of evolution as proposed by Darwin and Wallace in 1859 came along. I thought it might give some idea of how big a shift in perspective would have been needed for the average person back in 1859.

So, how old was the Earth commonly accepted to be? Well, it was mostly calculated using the generations and ages listed in the Bible. There’s a YouTube video published in 2020 which uses the chronology to calculate that, if people used the text literally, the world would have been thought to have been created in 4163 BCE.

The chronology that I think is most often cited is that of James Ussher, an Irish bishop. His date is 4004 BCE, which indicates that a sort of consensus appears to be forming between these old thinkers that the Earth was perceived to be roughly six thousand years old.

Consider, then, the contrast between this number and the age of the Earth which we’ve calculated today- about 4.54 billion years. Let’s suppose we make the number calculated by Ussher (5863 years old in 1859) equivalent to one step (which I’m going to approximate as a metre for the sake of my calculations). To walk this new age of the Earth, you would have to travel over 774 kilometres- very roughly 484 miles. For context, Google maps tells me that’s a longer journey than driving from Portsmouth to Edinburgh.

None of this is to say that the theory proposed isn’t correct- there’s a wealth of biological evidence to back it up. However, I find myself agreeing with the sentiment I saw expressed by Stephen Jay Gould– just because their ages of the Earth turned out to be wrong, doesn’t mean that we should deride the people behind it for that.

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Darwin’s Family Tree

To commemorate the anniversary of Darwin’s birth (12th February), I’ve created a Darwin’s Day episode which discusses the illness of Darwin and his immediate family and what could have caused this. There’s a 2017 paper, used as source material for the episode, which discusses this question. However, some of the relationships discussed (and indeed those not discussed) are hard to visualise. So, I’ve created a family tree of Charles Darwin to accompany the episode!

A family tree of Charles Darwin! The information here is collated from various Wikipedia articles for the people on the tree, as well as a website called Famous Kin.

Due to the nature of this kind of information, most of my information for this tree is sourced from the Wikipedia pages of these individuals. However, there’s also a website called ‘Famous Kin‘ I found, which I used to discover the descent from Edward III shown on the tree.

I’ve also shown some (but not all) the descendants of Charles Darwin on this tree, such as the actor Skandar Keynes– who played Edmund Pevensie in ‘the Lion, the Witch and the Wardrobe’, the novelist Emma Darwin, and Erasmus Darwin IV, a soldier who was killed during the larger Battle of Ypres in 1915.