This post was originally published on a now-retired blog that I maintained from roughly 2005 to 2013. As a result, there may be some references that seem out of date.
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Six million years back in time, we meet the common ancestor we share with chimpanzees, another million beyond that we meet the common ancestor we and chimpanzees share with gorillas, and another seven million beyond that we meet the common ancestor (the “concestor”) we, chimpanzees and gorillas share with orangutans.
It goes back like that all the way through 39 such “rendezvous” to the common ancestor all other forms of life share with eubacteria some uncounted number of millions of years ago. Along the way different tales are told by different life forms, each illuminating a different and interesting aspect of the evolutionary story.
The story is fascinating, but so is the raw chronology of it all, so much so that’s it’s worth repeating here.
- Rendezvous 1 - 6 Million of Years Ago - Common Ancestor with Chimpanzees
- Rendezvous 2 - 7 Million of Years Ago - Common Ancestor with Gorillas
- Rendezvous 3 - 14 Million of Years Ago - Common Ancestor with Orangutans
- Rendezvous 4 - 18 Million of Years Ago - Common Ancestor with Gibbons
- Rendezvous 5 - 25 Million of Years Ago - Common Ancestor with Old World Monkeys
- Rendezvous 6 - 40 Million of Years Ago - Common Ancestor with New World Monkeys
- Rendezvous 7 - 58 Million of Years Ago - Common Ancestor with Tarsiers
- Rendezvous 8 - 63 Million of Years Ago - Common Ancestor with Lemurs
- Rendezvous 9 - 70 Million of Years Ago - Common Ancestor with Shrews
- Rendezvous 10 - 75 Million of Years Ago - Common Ancestor with Rodents
- Rendezvous 11 - 85 Million of Years Ago - Common Ancestor with Laurasiatheres (mammals from “Laurasia”)
- Rendezvous 12 - 95 Million of Years Ago - Common Ancestor with Sloths, Anteaters and Armadillos
- Rendezvous 13 - 105 Million of Years Ago - Common Ancestor with Afrotheres (mammals from Africa)
- Rendezvous 14 - 140 Million of Years Ago - Common Ancestor with Marsupials
- Rendezvous 15 - 180 Million of Years Ago - Common Ancestor with Monotremes
- Mammal-Like Reptiles
- Rendezvous 16 - 310 Million of Years Ago - Common Ancestor with Reptiles and Birds
- Rendezvous 17 - 340 Million of Years Ago - Common Ancestor with Amphibians
- Rendezvous 18 - 417 Million of Years Ago - Common Ancestor with Lungfish
- Rendezvous 19 - 425 Million of Years Ago - Common Ancestor with Coelacanths
- Rendezvous 20 - 440 Million of Years Ago - Common Ancestor with Ray-Finned Fish
- Rendezvous 21 - 460 Million of Years Ago - Common Ancestor with Sharks
- Rendezvous 22 - 530 Million of Years Ago - Common Ancestor with Lampreys and Hagfish
- Rendezvous 23 - 560 Million of Years Ago - Common Ancestor with Lancelets
- Rendezvous 24 - 565 Million of Years Ago - Common Ancestor with Sea Squirts
- Rendezvous 25 - 570 Million of Years Ago - Common Ancestor with Starfish
- Rendezvous 26 - 590 Million of Years Ago - Common Ancestor with Protostomes (including insects)
- Rendezvous 27 - 630 Million of Years Ago - Common Ancestor with Flatworms
- Rendezvous 28 - ??? Million of Years Ago - Common Ancestor with Jellyfish, Anemones and Coral
- Rendezvous 29 - ??? Million of Years Ago - Common Ancestor with Ctenophores
- Rendezvous 30 - 780 Million of Years Ago - Common Ancestor with Placozoans
- Rendezvous 31 - 800 Million of Years Ago - Common Ancestor with Sponges
- Rendezvous 32 - 900 Million of Years Ago - Common Ancestor with Choanoflagellates
- Rendezvous 33 - ??? Million of Years Ago - Common Ancestor with “DRIPs”
- Rendezvous 34 - ??? Million of Years Ago - Common Ancestor with Fungi
- Rendezvous 35 - ??? Million of Years Ago - Common Ancestor with Amoebozoans
- Rendezvous 36 - ??? Million of Years Ago - Common Ancestor with Plants
- Rendezvous 37 - ??? Million of Years Ago - Common Ancestor with Remaining Eukaryotes
- Rendezvous 38 - ??? Million of Years Ago - Common Ancestor with Archaea
- Rendezvous 39 - ??? Million of Years Ago - Common Ancestor with Eubacteria
What’s so fascinating about this evolutionary table? Well, several things.
First, how detailed it is. Something that became apparent to me as I read this book which I would say is not part of the common man’s everyday understanding of evolution is just how much credible, scientific evidence there is for it. In this Christian Nation, one would have Joe believe that evolution is a theory full of holes. And sure, there are some holes on the chart, but look at how much of the chart is complete. Ninety-nine percent of the scientific community agree with the connections and chronology back to about 500 million years ago, and beyond that there is some disagreement about dates and the order of the connections, but virtually none about the general trend. That’s the fossil record, sure, but more and more that’s molecular data from the genomes of different species, and seeing which are similar and how similar and which are different and how different.
Next, note that it takes 70 million years to find a common ancestor with something that is not a primate and 310 million years to find one with something that is not a mammal. That’s an incredible amount of time and a testament to the true diversity of life.
Next, what’s up with the mammal-like reptiles stuck in between rendezvous 15 and 16? Well, they’re a branch of the evolutionary tree that died out completely and didn’t make it to the present day the way human did. There’s nothing alive today that shares a common ancestor with us from this branch, but the branch was once there and for hundreds of millions of years those life forms were just as real as we are. How many other evolutionary branches are like that? Don’t they say that over 90% of the species that have ever been have gone extinct and aren’t around today? You think 850 different species of cartilaginous fish is amazing? What about the 7,650 species that have gone extinct?
Just how big is this tree of life anyway? And exactly when did “we” branch off from plants, and what were “we” when we did this. Look at the rendezvous on either side. Amoebas and Eukaryotes. Simple, single-celled creatures today and however many millions of years ago the rendezvous took place. That’s what “we” and “plants” were both then, but today we are both infinitely more complicated, infinitely more diverse, and infinitely different from one another. Like compounding interest, it really shows you what evolution can do if you give it a few billion years.
And that’s what a friend of mine has grown fond of saying after reading this book. When you think of the six million years that have passed since our common ancestor with chimpanzees, or the 60 million years that have passed since our common ancestor with lemurs, or the 600 million years that have passed since our common ancestor with flatworms, you begin to realize that the differences that we think of as separating us today are infinitesimal specks of flotsam on the currents of time.
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This post appeared on Eric Lanke's blog, an association executive and author. You can contact him at eric.lanke@gmail.com.
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