evolution: when nothing happens; living fossil (Introduction)

by David Turell , Monday, March 07, 2022, 16:04 (781 days ago) @ David Turell

Tuataras are weird and basically unchanged for 190 million years:

https://www.tasnimnews.com/en/news/2022/03/07/2678410/fossil-reveals-secrets-of-one-of-...

"New Zealand’s tuatara look like somber iguanas. But these spiny reptiles are not actually lizards. Instead, they are the last remnant of a mysterious and ancient order of reptiles known as the Rhynchocephalians that mostly vanished after their heyday in the Jurassic period.

"And they truly are the oddballs of the reptile family. Tuatara can live for more than a century, inhabit chilly climates and are able to slide their jaws back and forth to shear through insects, seabirds and each other. They even possess a rudimentary third eye below the scales on the top of their heads that may help them track the sun.

"These bizarre traits make tuatara an evolutionary enigma, and a spotty fossil record of its long-lost kin has confounded paleontologists. Likely outcompeted by lizards and snakes, virtually all Rhynchocephalians went extinct at the close of the Mesozoic Era. Many left little more than dusty tooth and jaw fragments behind.

***

"The remarkable fossil was discovered in 1982 during an expedition to the Kayenta Formation, a fossil-rich outcrop in northern Arizona. This band of red rock was deposited during the early Jurassic period when the dinosaur reign was in its infancy. Around this primeval floodplain, early dinosaurs like the crested Dilophosaurus mingled with burly, crocodile-like creatures encased in armor. Underfoot scurried primitive, shrew-like mammals and this strange new reptile.

***

"The fossil illustrates that the bodies of modern tuatara emerged in the Jurassic era and have changed little in 190 million years. This supports the popular distinction that these remnant reptiles are “living fossils.” But Dr. Simões emphasized the differences: For instance, modern tuatara jaws end in a set of beaklike fused teeth that are absent in Navajosphenodon. (my bold)

"According to Kelsey Jenkins, a doctoral student at Yale who specializes in early reptile evolution, many lineages of Rhynchocephalians exhibited little change throughout their history. However, 200 million years is extreme. “The only things that are that highly conserved are things like horseshoe crabs and cockroaches — not a decent-sized reptile,” said Ms. Jenkins, who was not involved with the new study.

Researchers argue this lack of change may represent natural selection on overdrive. “Slow rates of evolution don’t necessarily mean absence of evolution,” Dr. Simões said. Basically, it’s the evolutionary equivalent of the adage: “If it ain’t broke, don’t fix it.” (my bold)

"While the discovery of Navajosphenodon helps flesh out a crucial chapter in tuatara evolution, much of this reptile’s back story remains hazy. Without more fossil discoveries, it will be difficult for scientists to determine exactly why these lone survivors appear to possess evolutionary cheat codes. (my bold)

“'Why the modern tuatara and their lineages have evolved so slowly for such a long period of time is a bigger question and a bit harder to get at,” Dr. Pierce said. “We need more fossils.'”

Comment: Note the bolds. They raise interesting questions. Darwinists wonder why no evolution. They expect responses to changing conditions. The tiny changes noted in Tuataras are just minor adaptations, not real advancing evolution. Why should there have to be 'cheat codes'? And 'natural selection in overdrive' implies 'where is the expected advance'? As if natural selection is a magical driving force that didn't have to work here. This is a distorted view purely based on an unthinking acceptance of pure old Darwin evolution theory. For my standpoint it all makes sense with God running the show. The Tuataras are in a minor ecosystem that needed no tweaking to maintain the supply of food need that is required since everyone has to eat.