Theologically speaking, evolutionary theory can sound very troubling (millions of years of activity before man comes onto the scene?). And at other times it can sound almost beautiful. The inter-connectedness of life is rather a humbling experience.
It’s baffling enough to think of such diverse creatures as humans, birds, and fish all are theorized to have a common ancestor. What I find nearly impossible to comprehend is what else the theory proposes. That immobile organisms (probably not the technical term so I’ll say “Vegetable Kingdom”) have a common ancestor with mobile organisms (the Animal Kingdom).
How is it that a human has a common ancestor with a banana? Can a banana eventually mutate into some sort of creature with four legs? And has anyone ever contemplated the idea that mutations could go in a backwards direction… That an animal’s descendant could, for some reason, go back to the vegetable kingdom?
I’m perhaps ignorant on the topic, but it just seems silly to think about it, at times.
I know that silliness is not a criteria for doubt … Nonetheless, I would like to know more about it…
“The inter-connectedness of life is rather a humbling experience.”
I hear you. And Darwin thought so too, agnostic though he was. In fact it was his hope that if people could see how related they were, not even just to animals, but especially to “other races” of humans, that maybe it would help put down the despicable treatment he witnessed being heaped on native races by colonizers. But alas, evolution (and science generally), just like Biblicism all prove to be no match for our human inclination to bend all formalized religious systems into self-serving justifications. He too (it seems to me) probably underestimated the true power of evil, and then even much more our need for Jesus Christ to rescue us from ourselves.
How is it that a human has a common ancestor with a banana?
People who have recently or are emerging from a lifetime of anti-evolutionary conditioning do often find it hard to break out of ingrained approaches to this subject. One of those deep ruts is the “hopeful monster” model for how evolution is supposed to work. Indeed how could such widely disparate things share any ancestor in common? Well … not all of a sudden! Everybody will agree about that. Here is where people like Dawkins can show their true strength. If you want a true sense of how evolution really works, I would recommend his “Climbing Mt. Improbable”, which is an excellent treatment of these types of questions, giving beautiful exposition of how it works.
If you want a deep and penetrating treatment of Christianity, go to authors who are/were both knowledgeably and passionately involved in it. If you want to truly understand evolutionary biology, go to authors who are/were knowledgeably and passionately invested in that. Dawkins qualifies for the latter category in spades.
Sorry Tim, but millions of years sounds like AIG and YECs, it is really Billions of years. 9.260 Billion years from beginning of time (Big Bang) to formation of Earth 4.54 billion years ago to 4.1 billion years of life on Earth to 200,000 years for our species homo sapiens.
Because the last common ancestor between a banana and a human was a bacteria. Read up on early life, the archeaa, bacteria, and singled cell organisms prior to animals and plants. It is fascinating what science has learned in just the past few years.
Merv and Patrick have given you good answers. I will just add that the answer to your question “can a banana evolve into something with four legs” is almost certainly no. Despite the tremendous diversity of life, there are also tremendous constraints on how evolution can work. And it doesnt go backwards. On another thread there is a discussion of Simon Conway Morris ideas about convergence. and the limits and inevitability of eovlutionary directions which might interest you.
There is no magic to evolution, although when we say we are descended from fish or bacteria (slime in the words of creationists) it might seem that way. We are NOT descended from plants. Nor are we descended from any modern animals. We have common ancestors with every living thing,
You are descended from your parents, but not from your uncles. But you do have a common ancestor with your uncles and aunts, namely your grandparents. You are not descended from me, but we have several common ancestors (who probably lived in Europe from 3 to 5 hundred years ago, and earlier). All humans had a common human ancestor (mitochondrial Eve and Y Chromosomal Adam). We also as a species had a common ancestor with all Neanderthals, and Denisovans. That was some hominin. And so on,
Where does it end? At a very small, one celled organism called LUCA the Last Universal Common Ancestor, who lived about 4 billion years ago. Yes, the interconnectedness of life is a beautiful thing, and I cannot imagine a more profound testament to the glory and majesty of the Creator of all.
Sy,
Nice post. Just one correction - mitochondrial Eve and Y chromosomal Adam, were not the LUCA of our species. Mt Eve and Y Adam are just two of our ancestors. There were many more. The LUCA of the entire species goes way back to much earlier times.
I like to point out that in those “much earlier times”, SOME individual would have been considered the FIRST “moral agent” in a theological sense.
The genetic constellation supporting this “first moral man” does not have to have been on the “Y” Chromosome, and almost certainly wasn’t on the genetic code for mitochondria.
Yes, of course. My writing is not always clear or complete. Thanks for the clarification, Patrick. I also agree entirely with George Brooks. Genetics is not all there is to life, especially not for humans.
Sorry Patrick. My bad. The point is “a lot of stuff went down”. When I said millions I years I was actually thinking of how long life has been here. In any case, as you point, life has been here longer… So I must have been thinking of how long multicellular life has been here (which to my understanding is somewhere in the the neighborhood of 660 million years).
Keep in mind, I’m not trying to poke fun here, I’m just trying to understand. I know it may sound like I am (it may sound reminiscent of creationist jabs). But I’ve moved passed mere mockery…
I was reading an article that Christy sent me — and it was saying that evolutionary theory predicts you’ll find reptile-bird immediate as well as reptile-mammal immediates. But it does not predict bird-mammal immediates.
Perhaps I’m running under the false impression that evolution can go in whatever direction it wants unexpectedly? But I’m also confused because I though that fish eventually produced offspring that grew legs and climbed onto the ground. But I’ve also heard that whales and dolphins used to have legs and climbed their way into the sea.
Not sure who said it, but that seems like a backward direction to me?
I agre with you totally! I’ve heard from both sides of the issue why evolution shouldn’t be trusted (see over here! Hitler liked his theory! Euthanasia? Abortion?). And then on the other-side people blame Christianity (ku-klux-klan using Bible verses to promote white supremacy? The inquisition etc.,)
The problem isn’t with Christianity or Evolution however. All it’s showing is how we, as humans, are capable of misusing ideas for our own selfish desires.
There’s probably a name for this kind of logical fallacy (emotional appeal?).
I wasn’t taking anything you wrote as “poking fun”. I appreciate your comments.
As for your question about whales, others here can give clarifying or correcting details since I am more familiar with the broad sweep of evolutionary theory and do not invest much time (as a physical sciences teacher) into the details of it, much less the latest updates/fossil finds.
But for what it’s worth, yes, whales share a common ancestor with hippos and prior land walking creatures which … going further back would have emerged from water at some point long before. (Patrick and others here will be happy to fill in all the details or make any corrections). Keep in mind that there is no “forward” or “backward” to the few mechanisms (natural selection pressures on variations) that we have scientifically theorized about.
Hippos are obviously at home in an aquatic environment, so it’s no great stretch to think of their “cousins” having evolved to become completely aquatic again.
“A New History of Life” by Peter Ward & Joe Kirschvink
"Sapiens- A brief History of Humankind" by Yuval Noah Harari.
They will both give you an up to date view on where the scientific thinking is at in 2015. I know Brad is worried that the atheism virus might infect your mind, but no worries, these book are completely secular and will help enormously as you reason things out. Science changes a lot, and it is best to be a current as possible so that when you do compare with Faith issues you have the most recent science to compare with. Plus the way your mind works, you will really enjoy them.
That’s a good question. I think that there could be something in the human genome that was later adapted into cultural morality. Like incest. I think that the human genome is such that you don’t find your sister attractive and seek a mate outside the family. I think there are genetically selected human traits like empathy and cooperation that are part of our genome and have lead to our evolving view of morality. But morality moves much faster than genes so the genetic influence is subtle.
no, evolution is single direction - forward and it is irreversible. Most changes are an accumulation of mutations and need several mutations to build upon the previous ones. For example, human intellience. It requires a big brain. But to get a big brain, need to cook meat. Humans needed many changes that were built on previous changes. Neanderthals had bigger brain than us, but went extinct. Both Neanderthals and Sapians have the brain capacity to do calculus but only humans do it. Whales have bigger brains than we do but because they haven’t gone through all of the steps we have, conscious thought coming from a whale seems way off in the future, if ever.
@Patrick
Isn’t that a bit of an over-statement? It depends upon the context of what you are looking at.
If you asked if the first animals without legs can evolve into animals without legs … the answer is, of course:
… but in the Earth’s case, you have to go all the way to snakes, right?
And some snakes STILL have legs.
Whales came from animals with legs… and now they don’t … but there are vistigial leg bones…
