Darwin's original sketchbook scribble depicted a branching tree with each 'leaf' representing one particular species. It changed forever our perception of who we are.
In 2009, whilst on holiday in northern Spain, I took with me a book about the Tree of Life called 'The Ancestor's Tale' by Richard Dawkins and Yan Wong. One day, whilst reading beside a path in the mountains, a group of pilgrims following the Camino de Santiago came into view. In order to greet them I closed the book and, as I did, was struck by its strap line on the front cover - a pilgrimage to the dawn of life.
A thought emerged. Instead of imagining a pilgrimage along the branches of this great tree, why not quite literally step into reality? In a location blessed with many footpaths, it might, with a little artistic licence, be possible to align selected branches with existing footpaths and create an actual 'pilgrimage to the dawn of life'. Dawkins' book imagines this journey backwards in time to avoid what he calls the 'conceit of hindsight' where people are tempted to view evolution as pointing towards its finest creation ~ the human race. By starting their journey from the tips of the branches (representing the present day) and heading back in time the authors offer a far humbler interpretation ~ one of our origins shared.
So in 2010, inspired by this vision, we laid the Tree of Life template over the Quantock Hills in Somerset and, on a day in May, populated the tips of our trails with groups of walkers representing the life-forms of their branch including ‘monkeys', ‘birds’, ‘plants’, ‘fungi’ or ‘bacteria’ and of course not forgetting 'ourselves’.
Strictly speaking all these trails should be the same length seeing as all extant species share the same origins. However, not everyone is keen or able to walk up to 15 miles and so we made the trails many different lengths so that people may choose their walking distance through the Trail adopted. Whichever trail chosen, all our walkers meet and join along a series of evolutionary rendezvous so that our ever increasing band of pilgrims arrive together at a place representing the origins of life some four billion years ago. Of course their meaning, in terms of reunification with common ancestors, is key and in order to come at the science from several angles, we also explore ancestral family trees. Perching peoples' family trees on top of the Tree of Life helps cement their connection with this immensely bigger picture.
If we are all to reach our goal in a sensible time frame, each step must represent thousands or even millions of years. In terms of the life forms with which we are most familiar, very little happens in the first few billion years of evolution, and yet, especially from a primate point of view, everything happens in just the last few million years. Given this, we decided to create three different scales over the Trail. At the beginning, in order to expand our mammal dominated period, each step represents 10,000 years back in time. Beyond this point, our time travel increases by an order of magnitude to 100,000 years per stride and then, for the last 2.7 billion years, by another order of magnitude to around a million years every stride. In this way we ensure a relatively constant procession of rendezvous throughout the Trail.
Like other pilgrimages the Ancestor's Trail offers a shared metaphorical journey towards a special place of significance although it differs in one important way ~ our walkers start from disparate locations and amalgamate along the way. Witnessing families and friends joining at these rendezvous is one of my favourite aspects of the event.
The event, whilst firmly rooted in science, was beginning feel symbolic. There followed many discussions about the purpose of this thing we had created and soon enough I began to search for a good cause it might benefit.
To affect almost any change humans link arms. Walking together adds a special dimension because we face in the same direction with our shared perambulations oiling good conversation and original thought. Once you join a pilgrimage there is an inescapable feeling that you have become part of a movement. Many people relish that sense of loss of self and deeply belonging within a greater purpose.
And in the Ancestor's Trail everyone really does belong. Every person on the planet, in fact every person who has ever lived and ever will live, and indeed every living thing on earth definitely belongs in this grand old Tree of Life. I was strongly attracted to this depth of inclusivity.
Of course evolution is one big biodiversity machine and science tells us that we really must urgently come together to protect life on earth. And what better concept around which to link arms? Visualise if you can the Tree of Life. Its profusion of leaves representing millions of species. Our human leaf holds on beside all the rest, and yet, we all know a terrible autumn is sweeping over its branches with many leaves perished, and others destined to lose their precarious hold all too soon.
We billed the event as a celebration because, along with every other life form alive today, we've made it! You and I are incredibly successful beings- not ONE SINGLE of your ancestors died before s/he first successfully reproduced, thus bringing your next nearest ancestor into the world. Viewed this way, inescapably, you personally represent 4 billion years of uninterrupted survival success. It'd be a crime not to celebrate such an achievement and celebrate we do on the Ancestor's Trail. And what celebration would be worth celebrating without the arts, and so we embraced music, drama, poetry and the visual arts to help us negotiate the bewildering evolutionary landscape revealed along the Trail. To add to this we have included live animal displays of bird's of prey, turtles and insects.
My aspiration is that wildlife charities will increasingly head up their own trails - for instance the RSPB for the 'bird trail' or Butterfly Conservation for the 'butterfly trail' to remind us of our shared mission in this respect. In return the event could raise funds or walking sponsorship for participating organisations. Given our belonging as part of nature, I would like to extend a welcome to human charities also.
But before we get carried away, of course this celebratory angle could be challenged for it is also true that the event could be viewed as one enormous funeral march. We extant species represent a tiny minority when compared to the vast roll call of extinctions lost along the way. Add this to the enormous challenges facing humanity as our population approaches double figure billions and our leading role in the present extinction event, and perhaps our efforts should be better interpreted as a protest march. Starting from disparate locations people walk towards a single place and although thus far this has been near water to signify the origin of life, equally this place could include seats of power or wealth. However, whilst I see potential here I leave this to others better placed than I to explore.
The Ancestor’s Trail was conceived in response to the International Year of Biodiversity and Darwin’s 150th anniversary and first took place in Somerset with forty or so friends and family. In 2014 the Trail moved to Epping Forest and the River Lee Country Park in Essex, and it has taken place there since thanks to the support of volunteers from Central London Humanists. One of their team struck upon the idea of starting all trails from public transport hubs to avoid car travel and parking issues. The UK and Canadian trails have been organised by Humanists but elsewhere by academic institutions and has now run at least twenty times in 5 locations - including New York State and Russia.
In 2011 Richard Dawkins became aware of the project, providing publicity and financial support, and in 2013 and 2014 he appeared in person as a speaker.