Cycads, such as this sago palm, have bulbous, egglike roots that harbor nitrogen-fixing bacteria. Since nitrogen can be a limited nutrient in many terrestrial ecosystems, this gives cycads a competitive advantage over the plants that grow around them.
Photo: Forest and Kim Starr, CC BY 2.0
Somehow, creationist frauds have managed to convince their dupes that new genetic information can only arise if created by a magic man in the sky who can suspend the laws of physics and make the impossible happen, because it is impossible for new information to arise. This is supposedly due to some law of physics which is always poorly defined, but somehow has something to do with thermodynamics and a thing called 'information theory'. 'Thermodynamics' and 'Information theory' are nice, sciencey-sounding words that give Creationist dupes a cosy warm feeling when they use them, because they imagine it makes them sound as though they understand science, just like real scientists.
And there are few things a science-denying Creationist likes more than thinking his/her superstitions have a sound scientific basis.
The facts however, refute this notion, as can be seen with this new study, which shows how new genetic information can arise perfectly naturally, without magic. So using 'thermodynamics' and 'information theory' to argue that science can't explain how new genetic information arises, makes Creationist dupes sound exactly like scientifically illiterate, science-denying idiots and the willing dupes of frauds.
This new study shows how frequent gene duplication and the subsequent evolution of these 'spare' genes was responsible for the evolution of the large and diverse group of plants known as gymnosperms that includes pines, cypresses, sequoias, ginkgos and cycads.
As the Florida Museum news release explains:
Sadly, the paper in which the team published their findings in Nature Plants is behind an expensive pay wall. In their abstract, the authors say:This event at the start of their evolution created an opportunity for genes to evolve and create totally new functions that potentially helped gymnosperms transition to new habitats and aided in their ecological ascendance.Plants are DNA hoarders. Adhering to the maxim of never throwing anything out that might be useful later, they often duplicate their entire genome and hang on to the added genetic baggage. All those extra genes are then free to mutate and produce new physical traits, hastening the tempo of evolution.
Dr Gregory Stull, Lead author
Florida Museum of Natural History Florida, USA
A new study shows that such duplication events have been vitally important throughout the evolutionary history of gymnosperms, a diverse group of seed plants that includes pines, cypresses, sequoias, ginkgos and cycads. Published today in Nature Plants, the research indicates that a genome duplication in the ancestor of modern gymnosperms might have directly contributed to the origin of the group over 350 million years ago. Subsequent duplications provided raw material for the evolution of innovative traits that enabled these plants to persist in dramatically changing ecosystems, laying the foundation for a recent resurgence over the last 20 million years...
Taking a closer look at gymnosperms
What makes gymnosperm genomes complex is they seem to have a proclivity for accumulating lots of repetitive elements. Things like ginkgos, cycads, pines and other conifers are loaded with all this repetitive stuff that has nothing to do with genome duplication.While having more than two sets of chromosomes – a phenomenon called polyploidy – is rare in animals, in plants it is commonplace. Most of the fruits and vegetables we eat, for example, are polyploids, often involving hybridization between two closely related species. Many plants, including wheat, peanuts, coffee, oats and strawberries, benefit from having multiple divergent copies of DNA, which can lead to faster growth rates and an increase in size and weight.
Professor Douglas Soltis, Co-author
Curator, Florida Museum
University of Florida.
Until now, however, it’s been unclear how polyploidy may have influenced the evolution of gymnosperms. Although they have some of the largest genomes in the plant kingdom, they have low chromosome numbers, which for decades prompted scientists to assume that polyploidy wasn’t as prevalent or important in these plants.
The diversity in cone structure, color, shape and size across gymnosperms, as evidenced by this female cone of the species Callitris pancheri, may have arisen as a result of multiple genome duplications.Photo: Nicolas Anger
Gymnosperm genetics are also complex. Their large genomes make them challenging to study, and much of their DNA consists of repeating sequences that don’t code for anything...Many of the cones in the podocarp family, such as those produced by the Podocarpus polystachyus shown here, look superficially similar to the fruit of some flowering plants.
Photo: Cerlin (CC BY-NC-ND 2.0)
However, a recent collaborative effort among plant biologists, including Soltis, to obtain massive numbers of genetic sequences from more than 1,000 plants has opened new doors for scientists attempting to piece together the long history of land plant evolution. Stull, now a postdoctoral researcher at the Chinese Academy of Sciences’ Kunming Institute of Botany, and his colleagues used a combination of these data and newly generated sequences to give gymnosperms another look.
Genome duplication gave rise to gymnosperms
By comparing the DNA of living gymnosperms, the researchers were able to peer back in time, uncovering evidence for multiple ancient genome duplication events that coincided with the origin of major groups.
Gymnosperms have undergone significant extinctions throughout their long history, making it difficult to decipher the exact nature of their relationships. But the genomes of all living gymnosperms share the signature of an ancient duplication in the distant past, more than 350 million years ago. More than 100 million years later, another duplication gave rise to the pine family, while a third led to the origin of podocarps, a group containing mostly trees and shrubs that today are primarily restricted to the Southern Hemisphere.
In each case, analyses revealed a strong link between duplicated DNA and the evolution of unique traits. While future studies are needed to determine exactly which traits arose due to polyploidy, possible candidates include the strange egglike roots of cycads that harbor nitrogen-fixing bacteria and the diverse cone structures found across modern conifers. Podocarp cones, for example, are highly modified and look deceptively like fruit, said Stull: “Their cones are very fleshy, have various colors and are dispersed by different animals.”
Here, we examine the relationship of various facets of genomic evolution—including gene and genome duplication, genome size, and chromosome number—with macroevolutionary patterns of phenotypic innovation, species diversification, and climatic occupancy in gymnosperms. We show that genomic changes, such as WGD and genome-size shifts, underlie the origins of most major extant gymnosperm clades, and notably, our results support an ancestral WGD in the gymnosperm lineage. Spikes of gene duplication typically coincide with major spikes of phenotypic innovation, while increased rates of phenotypic evolution are typically found at nodes with high gene-tree conflict, representing historic population-level dynamics during speciation.Once again, then we have a scientific paper which completely refutes Creationists' claims and shows that mutations such as gene and whole genome duplication can be, and indeed frequently were, responsible for the evolution of new taxons with unique characteristics, contrary to Creationist dogmas that you'll see confidently repeated endlessly as though they were scientifically established principles. Completely taken in by frauds like Behe, Ham and Dembski.
Creationism must, along with flat-Earthism, be the only popular science-denying belief that is so easily refuted that scientists do it regularly and without effort or intent, simply by revealing the facts of nature. This is because evolution is fact-bases while Creationism is counter-factual, or, in normal parlance, wrong. A lie perpetuated for extremist political ends that need people to believe falsehoods.
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