Where do we begin?

When asked where we came from, where do we begin?

If you mean “we” in terms of living beings, we have to go back to the single-celled blobs about 3.8 billion years ago, floating in the early waters of a very young Earth.

These solitary blobs were probably the first things, the first module of life that conditions then allowed. Far more ancient than you could fathom, this was the ancestor of all living organisms. Fast forward to now, and we know that a lone human being has about 60 trillion cells swimming to create and animate this enterprise called “life” and each day, those cells would have to work as they should or else, life will miss a knob, a connection here and there and dim out. From a single cell swimming in the sea of a tumultuous Earth almost four billion years ago, to trillions of cells in one organism now, all of us who live, whether we have limbs or eyes or brains, started with the same “umph” that the single-celled blobs had. Where did we begin as life? At sea, as cells, lonely solitary cells.

If you mean “we” as sexual beings, then the messy affair started about two billion years ago when these single-celled beings happen to get close and exchange “stuff” from within each of them and from there, more of them came to be, with each “offspring” not exactly like either of the parent but a mix. This clearly shows that sex has been around long before desire ever invaded the sex scene. Biologists still have conferences to debate on why sex had to happen when nature could just make exact copies of themselves. But it seems, sex has proven to be a pretty good way to fool other players in nature, such as parasites. The Origins feature of the August 2010 issue of the Scientific American cited leading biologists to say that sex is effective in scrambling the gene lottery enough to come up with more versions that could stand a chance against varied conditions and players. But they said sex may not be here forever because when sex partners disappear, nature finds a way to enable beings to reproduce by themselves like many reptiles do. So where did we begin as sexual beings? Certainly not with desire but as wandering, clueless single cells getting accidentally entwined to begin a biological exchange that would later be embroiled in so many controversies and human stories, two and half billion years later.

If you mean “we” as animals that have almost been totally squashed by great mass extinctions and revived by great rebirths caused by a temperamental Earth, then we still go back to the sea. Our ancestor was a pretty humble fellow, biologically speaking and we know this because we now have fossils from 635 million to 452 million years ago of primitive animals, relatives of jellyfish or marine worm and even those that began to show bilateral body symmetry like ourselves. This seemed to have been made possible by a surge in oxygen at this time. More oxygen made animals become bigger and more complex. I read Sean Carroll’s essay in the New York Times last July 16. He mentioned Darwin when he wrote to geologist Charles Lyell: “Our ancestor was an animal which breathed water, had a swim-bladder, a great swimming tail, an imperfect skull and undoubtedly was an hermaphrodite! Here is a pleasant genealogy for mankind.” Now we know from fossils that our earliest predecessors as animal beings were even “less endowed.” Where did we begin as animals? Sean Carroll wrote it best in his article, based on evidence so far: “Our earliest animal ancestor probably had no head, tail, or sexual organs, and lay immobile on the sea floor like a door mat.”

If you mean “we” as Homo sapiens, it has to be in Africa around 200,000 years ago. All those who live now, no matter how much whitening cream you regularly apply, trace their ancestors to this group. Recent findings featured in the cover story of the August issue of the Scientific American, by paleoanthropologist Dr. Curtis Marean and his team tell the story of a group of Homo sapiens who may have been the pool from where the first Homo sapiens walked out of Africa to populate the world. This was a special group because they survived the plummet of the Homo sapiens population caused by cold and drought in most other parts of Africa. They found a way to survive, taking refuge in the caves in the southern coast of Africa, where they were able to sustain themselves with abundant shellfish and marine life. This group also showed what could be among the earliest signs of human ingenuity in the tools that were found. From this population, we could trace our direct lineage as modern humans. So where do we begin to tell our story as modern humans? In caves in Africa, between 195,000 and 123,000 years ago being saved by the sea’s abundance when all else was drying up. The seas saved modern humans from an early disappearance in the life scene.

Where do we begin? Over four and a half billion years of journeying filled with high drama, the unexpected turns, the dead ends, the great dying of unspeakable numbers of life forms, the astounding rebirths against the odds, the stupefying variety, ingenious and supremely imaginative nature seeking, settling, shifting, shedding, segueing into the next version, the next adventure of life. We could begin in various points because there was no one single glorious time where we, as we are now, began. Pick a time, pick a gene, pick a way of birth. We began many times and the story of life still yearns to unfold.

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