Hello @John_Harshman. Given your expertise in avian phylogeneticts, I would like your informed opinion on the development of birds following the K-Pg mass extinction. My understanding is that only a few bird species survived and rapidly diversified post K-Pg.
Genesis 1:20-22 “… let birds fly above the earth across the vault of the sky… So God created… every winged bird according to its kind… let the birds increase on the earth.”
My questions for you, in reference for Genesis 1 are not related to how you interpret the text (that’s for other experts), but rather the scientific information.
Was there a mass extinction of birds at the K-Pg followed by a mass diversification and repopulation of the earth?
Are the majority of modern flying birds post-K-Pg species?
Did most genera of modern flying birds evolve between the K-Pg and the Eocene-Oligocene boundary (i.e. can it be said there was an early and rapid diversification)?
Did non-flying ratite species make it through the K-Pg with significantly and comparatively less extinction than flying species?
Any idea on how many species of flying birds survived the K-Pg and went on to be the ancestors of modern bird species?
Apparently. I say that because the bird fossil record in the neighborhood of the K/T boundary isn’t very good, so it’s hard to tell what happened.
All modern birds are post-K/T species.
No. Most genera are probably Miocene or later.
We don’t know of any non-flying ratites that made it through the K/T boundary or that lived before the boundary. The data suggest that loss of flight happened later.
No. We can suggest a minimum based on time-calibration of trees. If I recall, that minimum is around 7. But we don’t really know how diverse birds were before or immediately after the extinction.
Incidentally, any attempt to match Genesis 1 to reality is doomed to ignominious failure.
If you would entertain additional questions, here they are:
Moving up the phylogenic tree, if one were to consider “families” of birds instead of “genera”, when did most families of modern birds evolve?
As far as you know, did the Eocene-Oligocene extinction have a profound affect on birds? It seemed to affect mammals substantially, but I have not seen it attributed to a substantial impact on birds, or fish for that matter.
The reason I am interested is because each “Day” of creation is separated by a night (evening and morning) and this potentially implies, according to Ancient Near Eastern imagery, a chaos event separating each “Day”. In the Bible, God is over and above chaos creatures like the leviathan (which he creates) and the snake in the garden (another creature), and plies them to his own purposes. The same thinking would presumably apply to chaos events. Therefore I am investigating “chaos events” like the the Great Oxygenation Event (2.3 bya) , the Great Unconformity (850-680 mya), the K-Pg (66 mya), and the O-E (34 mya) as “chaos events” separating the Genesis 1 days of creation.
With the above explanation in mind, I am investigating whether one could say that “God created the various kinds of modern birds during the Paleocene and Eocene” whereas He created kinds of modern mammals like lions, bears, wolves, cattle, etc. during and after the Oligocene.
To you, does it seem possible to characterize the branching-off-point of extant modern bird lineages as substantially predating the branching-off-point of extant modern mammal lineages in a meaningful way?
Thanks for any thoughts you might have on these questions.
They’re spread all over. Also, the great majority of families are passerines, and the classification of passerine families have been in flux for several years. They may be settling down now. So it’s hard to answer that question.
The fossil record probably isn’t good enough to show this. Avian paleontology is highly dependent on a comparatively small number of lagerstätten.
There are several problems with this. First, you need a rigorous definition of “kind”, which is not going to happen. Second, the fossil record may not be very good at delimiting this. Genetics might work better, and you might check out this web site, Timetree, which might give you the information you want; but be warned that some of that may not be reliable.
Most importantly, any attempt to align Genesis 1 with science is doomed to fail.
Hi John. Thanks for sharing the Timetree link. That’s pretty interesting, but I do understand that the results generated from data like this can change as new studies are completed. I’m sure it is a dynamic field.
I’ve seen discussion on what “kind” means go two ways. One is to try to find some level in taxonomy that corresponds to a kind. That does seem problematic. I’m not sure that there is any phylogenetic level that is fundamentally significant. From a purely genetic stand point is there really a rigorous definition of what a “class” is, or an “order”, or a “family”? I think these are just conventions of convenience, although I could be totally wrong about that.
The other way is to consider it as “lay vernacular” which is almost certainly how it is meant to be taken. In that case, there is a different kind of problem. If someone asked “When did the passerines evolve?”, the answer could be anything from “They are constantly evolving.” to “They seem to show up in the fossil (or genetic) record about 52 mya.” or a number of other answers. In that case you are onto the problem you point out:
You see, said alignment comes down to the art of storytelling. Because, really, what is trying to be achieved amounts to a very “layperson level” creation story from 2000 BC aligned to maybe a kindergarten-level creation story from 2000 AD. It’s very big picture, non-technical, but yet true. Ever read one of the “brief history of earth” kind of write ups for kids on National Geographic or something like that? Of course they run through 5 billion years of Earth history and cherry pick 15 facts. Does that make it false, untrue, a lie? Not necessarily.
I’m pretty happy with this: Timeline and this Chart but I am trying to test and improve upon them.
Thanks for your interest and feedback. I really appreciate it.
You are correct. There is none. But if “kinds” existed, there would be.
No, you’re right.
Here’s the problem: it isn’t true. Your timeline is a fine example of forcefitting in which both the biblical text and the scientific facts must be twisted to make a common shape. It’s futile, it’s pointless, and it’s just wrong.
No problem, but if you really appreciated it you would take my advice and abandon this futile effort.
So this is interesting, because that is a very succinct statement. It can be taken as “truth in brief”. It might be hard to make the statement “more true” without making it more detailed on the one hand or generalized to the point of being uninteresting on the other.
So, since there are no real phylogenetic categories, we are left with “kind” approximately equal to “species”. The phylogenetic tree has nodes, and those node are where one species diverges into two species. That seems to be the source of all structure in the phylogenetic, correct?
“God created every winged bird according to its kind” simply means God instigated every speciation event of birds.
Dialoging with you is very helpful to me. You bring stimulating challenges to the discussion. I’m giving a lot of thought to your challenge:
The trick is to release the tension and let the Biblical narrative and the scientific facts blend comfortably. It is the tension points I am looking for. What makes it forced? It’s like pounding an octagonal peg into a heptagonal hole. Needs work, I agree.
Correct. However, the node at which one lineage diverged from another is not necessarily the point at which the living species formed. Consider the chimp-human node, for example. Neither chimps nor humans are as old as that node.
You can certainly believe so, in the sense that God could have caused every apple to fall from its tree, every rainbow to form, and every sand grain to reach the beach.
That trick, I’m afraid, is impossible.
Because Genesis 1 doesn’t say those things, and neither does science.