One day in June 1857 a postman was busy making his way along a quiet Kent country road. One of the letters he was carrying was about to complete its epic three-month and 12,000 kilometre journey. But this wasn’t the only notable aspect of this particular letter. It also contained an outline of one of humanity’s greatest discoveries and would ignite a chain of events that revolutionised our understanding of the natural world.
Five years earlier the author of the letter, Alfred Wallace, was sat in a boat deep in the Atlantic Ocean. It was a lifeboat. There was little he could but watch as the ship he’d just abandoned, the Helen, went up in flames. Wallace was on his way back to England after a four-year tour of South America. As a budding naturalist, he’d spend those years collecting valuable specimens that he could sell on the lucrative Victorian market. It was a market that possessed an insatiable appetite for such rare and exotic creatures. The intention was for the collection to earn him his fame, fortune and favour within the scientific community. Unfortunately, a miscommunication resulted in his specimens having not being sent back to England as intended. Instead, as he bobbed around in his lifeboat, he was forced to watch the four-year’s worth of work be engulfed by the flames.
Alfred Russel Wallace was born near Usk, Monmouthshire in 1823. At that time the region was part of England; although, it’s now part of Wales. His family moved to Leicestershire while he was young and it was here that he developed a passion for beetle collecting. Wallace became amazed by “their many strange forms and often beautiful markings or colouring” and was fascinated that roughly a thousand different species could be found within only a ten mile radius of Leicester.
Four years later Wallace’s interest had far outgrown the opportunities offered by Leicester. Inspired by Charles Darwin’s Beagle voyage around South America and explorer Alexander von Humboldt’s exploits around the same continent he decided to investigate the region for himself.
After four years of hard work Wallace had amassed thousands of unique and valuable specimens. But the region had taken its toll on his health. He had endured numerous tropical fevers and by 1852 his poor health had convinced him to return to England.
It was twenty-six days into the voyage when the disaster struck. A fire broke out forcing crew and passengers to abandon ship. Weakened by illness he felt “a kind of apathy about saving anything” and only saved a minimal amount of notes and drawings. Adrift upon a lifeboat deep in the Atlantic Ocean he could do little but watch as four years of hard labour, and his potential fortune, was engulfed in flames and sank beneath the waves.
After ten days drifting on open seas Wallace and his fellow passengers were picked up by a cargo ship and taken back to England. His return must have no doubt been a bittersweet moment. His intended fame and fortune had hinged upon his work, which was now ruined. He published an account of his trip, but, with all his diaries and notes having been destroyed, the lack of detail resulted in it being poorly received by the scientific community. Four years of work had resulted in almost nothing. Such a disaster could easily defeat a lesser man, but not Wallace.
Less than two years later he embarked upon a new expedition to SE Asia. He arrived in Singapore in 1854 with the intention of surveying the local wildlife and collecting specimens to sell. For eight years he toured the Malay Archipelago (modern Malaysia and Indonesia) collecting over 125,000 specimens. This collection included over 5,000 species new to science. But this was by no means his greatest achievement during the trip.
In 1856 Wallace missed a connection leaving him stranded in Bali and Lombok for months. This delay provided the opportunity to thoroughly investigate the local wildlife. The islands of Bali and Lombok are separated by only 20 miles of choppy sea, but their geographical proximity stands in stark contrast to their biological disparity. As Wallace walked up the beach of Lombok he was astounded. The two islands hosted completely distinct wildlife. To the northwest was found species of Asian origin, but to the east were almost exclusively species of Australian origin.
At that time people believed that God created specific species for specific environments. The islands were only 20 miles apart. They had the same climate. So why would two such similar environments exhibit such dramatically different flora and fauna? Wallace’s observation completely contradicted the accepted view.
It would be a long time before anyone had any notion of plate tectonics, but, despite this, Wallace still pinpointed the cause of the strange distribution. He suggested, correctly, that Asia and Australia belonged to two ancient landmasses. At some point in the past the sea level was lower allowing species to migrate between the islands. But the sea between the two islands is very deep, that’s why the water between them is so choppy. The animals were unable to cross this natural barrier. When the sea level later rose they were left trapped on the islands. This realisation gave birth to the science of biogeography. It’s a science that bridges the gap between evolutionary history and geological history. It explains the incongruity of disparate organisms occupying similar environmental niches in close proximity. Today the invisible line that Wallace saw is known as the Wallace line. It runs between the islands of Bali and Lombok, up between Borneo and Sulawesi before continuing north between Mindanao and the small islands of Sangir and Talaud. But even this great discovery wasn’t the greatest achievement of Wallace’s trip.
While suffering from a malarial fever one day in 1858 Wallace had a momentary inspiration. He was contemplating the question of species evolution. He had long since accepted the idea of evolution, but no one had yet proposed a satisfactory explanation of how it might occur. Well, no one had done so publically. Privately, Charles Darwin had been wrestling with the problem for over twenty years. Knowing how controversial his ideas were, he’d kept them largely to himself.
While fighting off his fever Wallace realised that natural variation within species would provide survival advantages to some while disadvantages to others. Those with advantageous traits would have an increased chance of survival allowing them to pass the advantageous traits on to their offspring. This was how species could evolve. Unwittingly, he had co-discovered the answer to one of life’s greatest mysteries. He scribbled down his fledgling idea and posted it to a colleague in England who he knew would be interested in the idea. In truth, he had no idea just how interested the colleague would be. The colleague was Charles Darwin.
The postman’s delivery of the letter shocked Darwin. He was unsure of how to respond to being ‘forestalled’. He had been sitting on his controversial theory for over two decades. Wallace’s co-discovery forced his hand. Darwin handed the letter to some friends who decided to present the two men’s ideas to the scientific community together. Meanwhile, Darwin hurriedly began work on the book that would introduce the two men’s argument to the world.
Science historian Dr John van Wyhe described the situation as “[O]ne of the greatest ironies in history. Wallace sends his essay to the one man in the world who has been working on this for twenty years. And Darwin, again the perfect gent, passes it to Lyell, and they decide to publish essays from them both.”
Over time Darwin’s association with the discovery greatly eclipsed Wallace’s. During the twenty years of working on the theory he’d accumulated masses of supporting evidence, and, after all, a theory is nothing without evidence. In addition, it was the publication of On the Origin of Species that brought the two men’s ideas to public attention. Wallace, meanwhile, expressed no resentment about this overshadowing and regarded himself a fan of Darwin’s work.
Although Wallace was highly regarded in his time, he has since been largely forgotten. It’s astounding that someone who contributed so much to our understanding of the world is not more widely appreciated. To help mark the centenary of his death, in 2013, efforts were made to try and address this. Part of this effort involved raising money for a statue to be placed in the gardens of the London Natural History museum. Those willing to donate more than £10 had their names added to a list and placed in a time capsule buried beneath the statue. I was keen to help reclaim Wallace’s place in history so I readily donated. On a visit to the museum last year I managed to locate the statue. My name now sits in the buried capsule awaiting discovery by future generations in the same way that future generations will hopefully now discover the story of Wallace so he’ll never be forgotten again.
Wallace is depicted holding his butterfly net. If you follow his line of sight you realise that he’s looking at a butterfly attached to the building.
As an aside, Wallace also made one of the earliest warnings about the vital need for conservation. Alarmed by the rate at which species were disappearing he said “Future ages will certainly look back upon us as a people so immersed in the pursuit of wealth as to be blind to higher considerations.” It’s amazing that words written in 1863 could be so relevant today.