Lucky LUCA Was Already Complex

Posted on October 5, 2011 in Cell Biology, Darwin and Evolution, Microbiology, Origin of Life, Origins

Simple to complex: that’s been the essence of evolutionary theory ever since Charles Darwin imagined some organic molecules coming together in a warm little pond eons ago.  Whatever simple life form emerged from his pond started his evolutionary process that led to the human brain.  But what if the “last universal common ancestor” was already highly complex?  What if bacteria and archaea are “devolved” remnants of a more complex ancestor?  That’s exactly what a new study is claiming.

Last universal common ancestor [LUCA] more complex than previously thought” is the headline on PhysOrg.  Here’s what’s out: “Many believe LUCA was little more than a crude assemblage of molecular parts, a chemical soup out of which evolution gradually constructed more complex forms. Some scientists still debate whether it was even a cell.”  Not according to a study from the University of Illinois at Urbana-Champaign: “New evidence suggests that LUCA was a sophisticated organism after all, with a complex structure recognizable as a cell, researchers report.”

The article goes on to describe discovery of an enzyme common to all three kingdoms of microbes.  This enzyme, vacuolar proton pyrophosphatase, has been found in prokaryotic bacteria, along with a structure that is “physically, chemically and functionally the same as an organelle called an acidocalcisome” that is common in eukaryotic cells.  Acidocalcisomes are complex organelles that help control osmosis.  They contain protein pumps and gates that actively transport water, calcium, and ions.  An analogous structure and enzyme is also present in archaea.  Conclusion: the “last universal common ancestor” (LUCA) was already complex enough to contain these organelles, along with their molecular machines, and therefore “may have been more complex even than the simplest organisms alive today,” according to James Whitfield, a co-author of the study published in Biology Direct.

Whitfield said that today’s bacteria may appear primitive because they are stripped-down versions of earlier complex cells.  Because they live in extreme environments and have to reproduce quickly, bacteria could represent specialized cells that are simpler than LUCA had to be.  “You can’t assume that the whole story of life is just building and assembling things,” he said.  The last sentence of the article is another quote by Whitfield: “We may have underestimated how complex this common ancestor actually was.

The “universal common ancestor” meme is common in evolutionary reports.  A separate example can be found in a BBC News story about a scientist from Northern Arizona University who watched living fish jump by flipping their tails.  All of a sudden she envisioned a mythical universal fish jumping ancestor: “It suggests that, rather than a rare adaptation that evolved in a select few species, the ability to leap on land is common among bony fishes. So many more of their ancient aquatic relatives might have invaded the land than had previously been thought.”  She immediately thought “In my mind, that opens up the fossil record to re-interpretation,” adding, “The last common ancestor of the two species examined in this study lived about 150 million years ago,” she said, “which implies that the behaviour is at least that old.

One should not think, though, that common ancestors are necessarily simple.  PhysOrg published another discovery from Oxford University that shows another complex structure found in every cell from bacteria to humans: snake-like structures called cytophidia (“cell snakes”) whose functions are unknown.  They move around in cells and seem to have something to do with an enzyme called CTP synthase that plays a role in the formation of CTP, a building block of RNA and DNA.  The enzymes become organized in structures that move throughout the cell.  “Cytoophidia have heads and tails and can move around. They really do look like snakes,” one researcher said.  Their numbers appear tightly controlled by the cell.  The discovery led to a general principle about cells that reverberates back on the LUCA story, too:

The cell needs an organized structure to bring this industry of biochemical reactions under control, with many processes cordoned off in separate chambers, capsules and compartments. It allows related reactions to be better controlled and regulated, with the right concentrations of the different molecules brought together in the right environment. After all, you don’t just bung all the ingredients into a chemical engineering plant, a brewery or a baking tin imagining that the recipe will be fine.

“The beauty of a well-organized cell has not been appreciated by everyone. Without the structure, a bag of the same amounts of all the molecules would not do the same thing as a living cell,” explains Ji-Long. “Compartmentation could be a general feature for many enzymes in a cell,” he believes.

The number of essential parts of a free-living cell is growing.  This puts pressure on evolutionists to (1) explain how these complex structures and enzymes each emerged individually without a designer, and (2) explain how the last universal common ancestor got them all together at the same time, in the right concentrations, in the right compartments, working in a coordinated fashion, encoded in DNA, with machinery to replicate the entire cell faithfully, so that natural selection could act on future generations.

The fish story is just that (a fish story), but the LUCA story provides continuing confirmation of a trend seen for a decade (search on LUCA in our search bar, or go to 07/12/2010 “Bacteria Too Complex to Be Primitive Eukaryote Ancestors,” 01/14/2008 “Bacteria to the Future”, and 2/29/2004 “Was Their a Single Common Ancestor for All Life?” where Whitfield and the U of Illinois crew were struggling seven years ago with the LUCA myth).  It confirms again that bacteria cannot be considered primitive transitional forms from the “RNA World” or whatever other speculative scenario the evolutionist wants to conjure up, as if “primitive” prokaryotes “emerged” from a chemical soup, then “tinkered” for a billion years or more before becoming eukaryotes.  It puts more strain on origin-of-life scenarios, because the first cell had to “innovate” all this machinery early on by a blind, purposeless, unguided process.  We report this not that one must accept the LUCA myth; it just shows that even using their own assumptions, evolutionists are having a harder time against the facts.

Notice in the article that the lead author, Manfredo Suefferheld, who found the acidocalcisome in bacteria in 2003, said that finding organelles in bacteria went against tradition.  “It was a dogma of microbiology that organelles weren’t present in bacteria,” he said.  Science would be better without dogma.  Darwinism puts the fog in dogma, producing fogma, a dogma so thick you can’t see it unless you are outside of it.  The Darwin Party then puts the dog in fogma, sending their attack dogs barking and biting anyone who tries to clear the air.

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