Despite Dozens of Authors, PNAS Paper Fails to Explain Bird Evolution
Evolutionists admire good drivers. Their language is full of “driving forces” and “environmental drivers” that bring forth endless creatures most beautiful. The environment is Darwin’s Uber, driving animals to amazing new fitness peaks and dramatic adaptations. One little problem: the drivers are blind and don’t care about the passengers.
Look how the word “driver” is used in a PNAS paper by no fewer than 33 authors, “Earth history and the passerine superradiation.” Passerines (perching birds) comprise the largest order of modern birds, including all the songbirds. They are thought to have undergone a “super-radiation” after the dinosaurs went extinct. What would ever drive birds to evolve in all directions? Surprisingly, this paper tells us what probably did not drive them to evolve:
The phylogenetic hypothesis of passerine relationships and the time line we estimate for passerine diversification reconcile the evolutionary history of this group with paleontological, geological, and climatic data. We find that passerine diversification is driven by dynamics that are more complex than simply Cenozoic temperature change or ecological opportunity associated with the colonization of new landmasses. Still, the drivers of diversification within this group remain incompletely understood. Denser sampling of passerine lineages, combined with improved sampling of the passerine fossil record (particularly outside of Europe and North America), is needed to refine our estimates of lineage-splitting events and tease apart those macro- and microevolutionary factors that were responsible for the diversification of this extraordinary group. [Emphasis added.]
It’s Complicated, You See
Perhaps they didn’t need drivers because they had wings. Whatever the drivers were, they remain “incompletely understood.” It’s complicated, you see; no longer can evolutionists find a temperature driver or a continental-drift driver. Evolution is “driven by dynamics that are more complex” than that.
Our phylogenetic results refine our knowledge of passerine diversity and yield divergence dates that are consistent with the fossil record, and our macroevolutionary analyses suggest that singular events in Earth history, such as increases in Cenozoic global temperature or the colonization of new continents, were not the primary forces driving passerine diversification.
Something was driving them. What was it, if not the usual “singular events” like climate change or continental drift? Let’s look for other “forces” that evolution could use.
Taken together, these results suggest more complex mechanisms than temperature change or ecological opportunity have controlled macroscale patterns of passerine speciation.
“C’mon Over, Finches!”
Can “ecological opportunity” work as a driver of macroevolution? Let’s say New Zealand separates from Gondwana. Does the island advertise to the birds somehow, saying, “C’mon over, finches! Bring the whole nest with you. We’ll make you a starling!” Does a mindless island advertise its temperate climate to potential buyers? No, these 33 evolutionists confess; it’s “more complex” than that. Well, what other “mechanisms” or “factors” can Darwin hire for Uber-(macro)-evolution? Here are some of their suggestions:
- A carbohydrate-rich diet
- Mass extinction events
- Fragmentation of habitats
- Melting glaciers
- Differences in food preferences
- Habitat availability
- Antarctic ice sheets, glaciation
- Closing corridors for migration
- Global warming
These are all mindless factors that couldn’t care less what birds do. A glacier won’t build a chickadee. The list is also highly subjective. The authors provide no measurements or laws, like “For every ton of glacial melt, an Arctic tern will gain 2 mm of wing span.” Even if they could, association is not causation. Most notably, the paper lacks any obvious connection to Darwin’s mechanism. One can’t find any mention of mutation or selection in this paper. It’s hard to see how any of these blind environmental “drivers” could call up the beneficial mutations needed to diversify the passerine birds into 6,000 species we know today.
Devolution in Action
In a recent ID the Future podcast, Darwin Devolves author Michael Behe showed that the amount of evolutionary change available to Darwin’s mechanism, according to actual data on Darwin’s finches, is limited to the species and genus level. He likens this to a matter of about 50 cents’ worth of change out of a hundred thousand dollars. The same small-scale change is observed in many other diverse species, such as anole lizards in the Caribbean, honeycreepers in Hawaii, and cichlid fish in Africa. Moreover, the genetic changes actually observed involve breaking or losing pre-existing genes, as Behe explains in detail in his new book Darwin Devolves. Such “devolution” may help an organism survive better in a given environment, but at the expense of its “genetic patrimony.” Adaptation, therefore, makes evolution self-limiting. The organism will not get back what it has spent. It is driven into poverty, and eventual extinction. Photos of those pathetic blunted wings of flightless cormorants on the Galápagos come to mind. Flightlessness helps them in that specific environment, but look at the glory they lost compared to their flying ancestors.
However diverse birds became after the dinosaurs went extinct, therefore, they are less “fit” than their predecessors. Darwin’s Uber drivers are driving them extinct, cashing out their genetic 401K resources so that they cannot get out of the ruts they get adapted to.
Far Short of Scientific Standards
Dozens of evolutionists contributed to that PNAS paper. They tried hard to identify the “drivers” that produced Uber-evolution in passerine birds. Yet the paper falls far short of scientific standards of measurement. The only genetics they discuss is phylogenetics, collecting sequence data for the purpose of building trees, not for identifying beneficial mutations that might have been selected. Convinced that all birds arose by Darwin’s unguided mechanism, they work backwards, reasoning: Birds evolved, therefore some poorly understood mindless processes must have driven them to evolve. When bird appearances don’t correspond to the environmental drivers, they adjust the rates of evolution to force a match. This is fake science — belief driving conclusions.
Scientific understanding should rely on objective, measurable data. Not surprisingly, these 33 scientists arrive at very little understanding.
Although we are beginning to understand how Earth history affected the early diversification of modern birds, we understand much less about the macroevolutionary factors that affected diversification within specific major avian subclades, including the hyperdiverse passerines (order Passeriformes).
Hyper-(uber)-diverse passerines deserve better drivers than blind ones that don’t care where they are going. The scientific public deserves better understanding than subjective stories driven by dogma. Let’s see them discover some beneficial mutations actually getting selected. Most likely, the record will show a lot of broken and blunted remnants of genetic patrimony that used to be flush with capital.
Photo: No glacier built this boreal chickadee; by David Mitchell [CC BY 2.0], via Wikimedia Commons.