“Do you ever wonder what it all means? Like, what’s our purpose?”
Ellen cringed. She’d heard that question asked in that tone so many times. She knew it wasn’t a real question, more an attempt to sound profound. She tried not to listen, she tried to focus on the cocktail on the bar in front of her.
“Why are we here, you know?”
It was no good, the man’s voice was too loud, Ellen turned on her stool and looked. She saw a young man sitting in a booth with a young woman. He was grinning and talking, she was frowning and listening. Ellen was about to turn away, but the young woman interrupted and she was curious.
“Don’t you think it’s a redundant question?” The young woman said. “You can’t have evolution and a meaning of life, they’re not compatible.”
The young man’s grin faltered. “What’s evolution got to do with it?”
“It shows we weren’t created for a purpose,” the young woman said, “it shows we’re just another species of animal.”
“You shouldn’t call us just another animal. I mean, look at what…”
The young woman interrupted him again. “Oh sure, we’re an exceptional species, but just because we have the cognitive ability to question our purpose, it doesn’t mean we have one. Evolution shows us the Universe wasn’t created for us, we have no more right to a purpose than dolphins or squirrels or wasps.”
The young man didn’t look happy. Ellen could guess what was going through his mind. He’d met an attractive young woman and was trying to impress her, someone must have told him girls like deep guys and he was giving it his best shot, but it wasn’t going to plan.
The young man rallied though, his grin was back. “But what if something helped us evolve, like aliens, like in that film? Maybe they’ve got a plan for us?” He sat back and looked proud; point, counter-point.
The young woman looked tired and bored. Ellen could guess what was going through her mind too. She felt sympathy for her, clearly a kindred spirit, Ellen knew she’d be horrified if she found out the young man was right. But she’d find out soon enough, once Ellen published her latest paper.
The evidence had accumulated slowly, it had taken decades to see the full picture. It all began for Ellen in school when she read about the pathogens that infect animals and change their behaviour – the fungus that turned ants into zombies, the parasite that made rats take an unhealthy interest in cats. It was amazing how much these tiny organisms could change the behaviours of their animal hosts. How something so small could have such a big affect.
Next came the discovery of the huge diversity of bacteria and fungi living within us, we found we contained multitudes. Our bodies were no longer singular entities, we were walking ecosystems.
Incredibly, scientists found that these microbiomes affected our thinking and behaviour. The microbes living in our guts influenced our brains. Ellen was hooked.
Her first breakthrough was the discovery of S. socii during her PhD. Dubbed the ‘fun-guy’ by the popular press, Ellen found it manipulated human behaviour to make us more social. That first Nature paper had ignited Ellen’s career, funders had fallen over themselves to throw money at her. She’d put a lab together to uncover more of S. socii’s secrets.
Ellen had originally assumed the fungus-like organism spread by making its hosts more social and thus more likely to find a mate and reproduce. The children would be born carrying the pathogen, and so the cycle would continue. A neat idea, but far too simple, far too innocent.
As discovery followed discovery a more complex picture emerged. As her lab transcribed more and more variants of the parasite they made an S. socii family tree. They traced the first infections back 50,000 years in time, somewhere in North Africa or the Middle East. That result had given Ellen goosebumps.
She looked back over at the couple in the booth. They were sitting closer now, both of them smiling. Perhaps the young man had proved charming after all, or perhaps S. socii was working its magic?
Increased sociality was only one symptom of the infection. The pathogen improved cognitive skills and problem solving. It enlarged areas of the brain associated with language and art and music and mathematics. The conclusion became unavoidable.
Up until 50,000 years ago Homo sapiens had been just another animal, as the young woman had said. We were intelligent, we used tools, but we were no different from the other Homo species, just another intelligent hunter-gatherer ape roaming the land in small family groups.
For hundreds of thousands of years we barely changed, but then something happened, a Great Leap Forwards. Art appeared, and religion, and agriculture, then towns, cities, empires, pyramids, computers, and space exploration, all in quick succession, relatively speaking. What caused the change had long been a subject of debate, until S. socii.
A couple of months ago a collaborating lab in the States made another breakthrough. They found a handful of unusual amino acids in S. socii, an unknown class of proteins, chirality all back to front. A different type of biology. No one had used the word panspermia yet, but everyone was thinking it, surely?
Ellie wondered how the couple would react when they found out that something had visited us 50,000 years ago, and that it had infected us with an alien fungus that spread from world to world via the creation of space-faring host civilisations. Would the young woman be appalled to learn we had an extra-terrestrial creator and a purpose? Would the young man be disappointed to find out our creator was a microbe, and that our purpose was replication?
Ellen turned back to her cocktail. Better to leave them to their courtship, let S. socii get on with its business.