May 15, 2019 | David F. Coppedge

Unusual Fossils Call for Unusual Explanations

Some recent fossil finds require creative storytelling, but the science is the data –not the story.

Marine organisms in amber

Ammonites, which normally live in the ocean grew sometimes to immense sizes, but some were tiny. An ammonite and some marine gastropods (e.g., snails) have been found in Burmese amber said to be mid-Cretaceous in age (99 million Darwin Years), as reported in PNAS by the Chinese Academy of Sciences. Some 40 different organisms were found in the amber. Do these creatures show signs of millions of years of evolution? The summary in says,

Of the terrestrial fauna found in the amber, mites are the most abundant. Also present are spiders, millipedes, cockroaches, beetles, flies and wasps, most of which would have lived on the forest floor.

Of the marine fauna, in addition to the ammonite itself, sea snails and sea slaters are present. The slaters are like those living on the seashore today.

Sea slaters, also called sea roaches, emerge at night to feed on seaweed and detritus.

Amber, or fossilized tree sap, usually contains terrestrial organisms. To get a mixture of marine and terrestrial fossils embedded in a single piece of amber is certainly unusual, and calls for explanation. The researchers drew a mental picture:

But how on earth did the ammonite, an extinct sea-dwelling relative of squid, get preserved in a piece of amber that also contains land-based animals? The ammonite and sea snail shells offer possible clues.

The shells are all empty with no soft-tissue, so the organisms were long dead by the time they were engulfed by resin. The outer shell of the ammonite is broken away and the entrance of the shell is full of sand. The amber also contains additional sand.

The most likely explanation for the appearance of both marine and terrestrial organisms within the amber is that a sandy beach covered with shells was located close to resin-producing trees. The flying insects were trapped in the resin while it was still on the tree. As the resin flowed down the tree trunk, it trapped organisms that lived near the foot of the tree. Reaching the beach, it entombed shells and trapped the slaters living there.

The story may sound reasonable, but without evidence of this kind of thing happening today, it remains speculative.

Flight Twice Lost

White-throated rails are shorebirds that live near Madagascar. Live Science announced, with apparent exclamation, “This Bird Evolved into Existence Twice — Thousands of Years Apart.” Dating the fossils in Darwin Years leads to the hypothesis that on two different occasions, flying species landed on the Seychelles Islands and lost the ability to fly. Reporter Yasemin Saplakoglu calls this a case of “iterative evolution” — a repetition of a previous case of evolution. On the second occasion, “the birds, once again evolved out of their ability to fly.”

But is this really evolution? What does it mean to evolve “out of” a trait? Like the many examples known of blind cave fish and other cave dwellers that have lost eyes, this represents devolution, not evolution. It’s much easier to lose the ability to fly than to evolve it. Michael Behe’s newest book Darwin Devolves gives many examples of organisms surviving by breaking genes and throwing away traits. Sometimes loss of a trait is beneficial. He gives the example of taking the doors and hood off a car. If your biggest priority under certain environmental conditions was getting good gas mileage, driving without doors and a hood would help. Neo-Darwinism, he shows, would be incapable of evolving back “in” to a car with doors and a hood. In the same way, these white-throated rails found it beneficial to not waste energy on flight, but would anybody consider that evolutionary progress?

Speaking of flightlessness, an international team tried to figure out how it evolves, reports They concluded: convergent evolution, part of the Darwin Flubber recipe. They did worry about scaling, though; if one bone shrinks, how do other bones stay in balance?

“If you think about it, there’s lots of ways to break something,” he said. “There are a bunch of steps early in limb development where, if a protein doesn’t get expressed, it’ll just turn the system off and you don’t get a limb. But this is actually a complicated shift in body scaling. You can’t just willy-nilly grow limbs to different sizes, so … the fact that it’s important they maintain functional hind limbs constrains the system and might be why we see this convergent pattern.

Complicated as the devolution process sounds, it only means that ones that didn’t scale successfully didn’t survive. “What it boils down to, Sackton said, is that birds have a limited number of options to pursue when it comes to the loss of flight, and so various species have gone to the same well again and again.” Convergent devolution is not particularly surprising. The new motto maybe should be, “Devolve or perish.”

Rapid Burial of an Ecosystem

A fossil graveyard on the Iberian Peninsula, considered “hugely important” to paleontologists contains quite a mix of animals: “dinosaurs, mammals, crocodiles, pterosaurs, lizards, tortoises, amphibians and fish dating back to approximately 130 million years ago” have been discovered, says The scientists, believing as they obviously do in millions of years, ask questions about the age of the animals, concluding they were juveniles. They also ask about the fossilization process. But the important finding that seems to escape their questioning is this: “they were able to deduce that these bones were subjected to rapid burial, and soon reached the phreatic level in which the fossilization processes had already taken place.” Isn’t that unusual? Where on earth today is rapid burial fossilizing an entire ecosystem, from ankylosaurs to mammals and fish?

These fossil finds show evidence of either devolution or flood burial. By steadfastly holding to Darwin Years in their moyboy schemes, and by trusting that Darwin can make humans out of bacteria, and by refusing to consider the possibility of a wide-scale flood, paleontologists restrict their explanatory toolkit. So careful are they to avoid evidence that the Bible is right, they back into improbable just-so stories. That’s the science-stopper.




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