Grading Evolutionary Success Claims

Reporters often credit Darwinian evolution for explaining mysteries in biology. Let’s play teacher and grade their papers.

Here’s what we’re looking for. A good scientific explanation:

1. Should provide adequate causes for effects.
2. It should consider other causes and rule them out (for neo-Darwinism, positive selection instead of neutral drift).
3. It should be general enough to fit a theory, but specific enough to identify details in the causal chain: not  just “it evolved,” but “this mutation happened to this gene, conferring a specific fitness benefit that spread through the population at this time and place.”
4. A good explanation should be testable and falsifiable.
5. It should be empirically adequate, true to the observations without invoking occult phenomena or ad hoc theory-rescue devices.
6. It should avoid logical fallacies, like non-sequitur, post hoc, personification, glittering generalities, etc. (see Baloney Detector).
7. It should remain true to the theory’s core assumptions (for evolution, unguided material processes without teleology).
8. It should be powerful enough to convince skeptics. For Darwinism, macroevolution must be demonstrated. Changes need to be significant enough to exceed the limits of variation that creationists accept.

Here we go:

Winged seeds:

Scientists at the University of California at Berkeley say, “Conifers’ helicoptering seeds are result of long evolutionary experiment.” Who hasn’t enjoyed throwing samaras (winged seeds) into the air and watching them twirl? “The whirling, winged seeds of today’s conifers are an engineering wonder,” Robert Sanders writes, “and, as UC Berkeley, scientists show, a result of about 270 million years of evolution by trees experimenting with the best way to disperse their seeds” (personification fallacy).

Evidence, please: Cindy Looy found samaras from fossil conifers in Texas. They contained a variety of shapes, from two-winged designs to the single-winged variety seen today. Her team filmed how well the various types flew. The single-winged samaras stayed airborned twice as long. Most conifers today have the single-winged, good-flying kind.

Teacher comments: Initial diversity is the opposite of Darwinian expectations. Looy says the best flyers were already there from the beginning; where did they evolve from? The presence of double wings could have been adaptive in certain conditions. Sample size too small: only fossils examined were in Texas. Some of the forms could have been maladapted mutants. Personification fallacy: article says the trees “experimented with the best way” to disperse their seeds. Rest of the article consists of just-so storytelling. Grade: F.

South American mammals:

Several reporters jumped on this claim from the University of York: “Protein the Clue to Solving a Darwinian Mystery: Scientists at the University of York provided the key to solving the evolutionary puzzle surrounding what Charles Darwin called the ‘strangest animals ever discovered’.” “The South American native ungulate Macrauchenia patachonica had a number of remarkable adaptations, including the positioning of its nostrils high on its head,” Science Daily‘s photo caption reads. “This implies that Macrauchenia may have had a mobile proboscis, as pictured here.” These native ungulates disappeared about 10,000 years ago, the article claims. The origin of these ungulates has been a mystery since Darwin’s days, the article says, because “With all of these conflicting signals, they couldn’t say whether these ungulates were related to giant rodents, or elephants, or camels — or what have you.”

Evidence, please: the scientists were able to collect collagen samples and sequence them. They sequenced “48 fossils of Toxodon platensis and Macrauchenia patachonica, the very species whose remains Darwin discovered 180 years ago in Uruguay and Argentina.” Live Science says that only 5 of them had any protein sequence information. On the basis of that, they determined that these animals were perissodactyls, “the group that includes horses, rhinos, and tapirs.” This makes them part of Laurasiatheria, one of the major groups of placental mammals. The relationship “corroborates a view held by some leading paleontologists that the ancestors migrated from North America 60 million years ago, probably just after the mass extinction that killed off non-avian dinosaurs and many other vertebrates.”

Teacher comments: All that the evidence shows is that certain species of ungulates that lived in South America in the past are gone. That’s true of many species (saber-tooth cats, North American lions and camels, and many more). These complex mammals were full-fledged ungulates, adapted to their environment. Nothing is proved about their origin; just a claim that the data “corroborates” a claim about their migration made by “some” leading paleontologists (an indefinite claim; who? Who calls them “leading”? Where’s the counter-argument?).  But if they migrated, they already existed in North America. If they were related to tapirs, which have a mobile proboscis, there’s no new characteristic that was not already extant. There is no evolution here, despite the repetitive name-dropping of Charles Darwin. Science Magazine says that only “subtle changes” were found in the collagen sequences. Creationists would have no problem with the microevolutionary variations described. There are also embarrassing admissions that soft tissue like collagen was found, but that DNA could not last in warm, wet conditions (Science Mag says that collagen can last 10 times as long as DNA). Fallacy of circular reasoning in claiming collagen can last for millions of years, just because the evolutionary dates for these fossils are tied to evolutionary assumptions. Some value for recovering collagen sequence information, but that’s not evidence for evolution. Grade: D-.

Whale ears:

A Smithsonian press release announces, “Smithsonian Scientists Reconstruct Evolutionary History of Whale Hearing Using Rare Museum Collection.” The scientists know that hearing and echolocation in whales is very complex. “Whale ears are incredibly complex organs,” said Maya Yamato, the  lead author of the study. “Although scientists know that hearing is one of the most important senses that whales use to communicate, navigate and search for food in their underwater world, we are still searching for clues about how their ears actually work.”

Evidence, please: “The researchers used noninvasive biomedical imaging techniques to trace the development of fetal ear bones in 56 specimens from 10 different families of toothed and baleen whales. They observed how ears develop in unborn whales of modern species, and compared these changes with those reflected in the fossilized ears of extinct whales over the course of millions of years. Their findings confirmed that changes in the development of ear bones in the womb paralleled changes observed throughout whale evolution, providing new insight about how whales successfully made the dramatic evolutionary shift from land to sea and adapted to hearing underwater. As whale ears continue to mature in the womb, these basic mammalian structures rearrange to form the ‘acoustic funnel,’ which may play a critical role in underwater hearing. The position of the acoustic funnel also seems to be significant—some baleen whales have a funnel that faces sideways, while all toothed whales have cones that are oriented towards their snouts. These positions correspond with previously described sound reception pathways in each group.”

Teacher comments: No evolutionary evidence of the neo-Darwinian kind was found, despite the headline’s boastful claim to “reconstruct evolutionary history of whale hearing”. The structures developed in extinct whales the same way they do in modern whales. The article contains this promissory note: “Yamato and Pyenson’s nondestructive approach to exploring whale ears could facilitate additional studies on the same specimens and potentially act as a springboard for learning more about the evolution of other senses in whales.” Sorry, but promissory notes don’t count toward the grade. Gotta cash out the claim with evidence. Despite the busy work with CT scans, it didn’t help Darwin’s score. Grade: F.

More examples could be provided, but the material would get tediously repetitive.

Stay tuned to CEH for more exciting episodes of the Reality Teacher against the Darwin Imagineers!