2020/09/18

Genetic erosion is an inevitable phenomenon

Genetic erosion is the most significant reason for collapse of biodiversity - Evolution is a myth

https://onlinelibrary.wiley.com/doi/full/10.1111/eva.12564

Excerpts:"Genetic erosion is a major threat to biodiversity because it can reduce fitness and ultimately contribute to the extinction of populations."

"Over the last few decades, different components of biodiversity, from populations to ecosystems, have experienced a massive reduction in genetic diversity (Hughes, Inouye, Johnson, Underwood, & Vellend, 2008). In vertebrates, most threatened species have seen their genetic diversity reduced over the last few hundred years (Li et al., 2016; Willoughby et al., 2015). Most countries worldwide report significant genetic vulnerability within their plant populations: with, for example, roughly half of forest species being threatened (FAO, 2010, 2014). Furthermore, due to prolonged and intensive artificial selection, the effective population sizes of major domesticated livestock breeds rarely exceeds a few hundred individuals (Leroy et al., 2013), despite their often very large census sizes. Thus, many domestic breeds of high heritage value also need management to maintain genetic diversity (Bruford et al., 2015)."


"A growing number of surveys of natural loss‐of‐function (LoF) variants have been carried out in vertebrates (Das, Panitz, Gregersen, Bendixen, & Holm, 2015; Groenen et al., 2012; MacArthur et al., 2012; Sulem et al., 2015; de Valles‐Ibáñez et al., 2016) and plants (Cao et al., 2011) with the number observed ranging from hundreds (332–696 in six great apes) to thousands (6,795 in Icelandic humans and ~12,000 across 80 Arabidopsis populations). Most recently, Rogers and Slatkin (2017) identified a much larger number of deletions retrogenes, and nonfunctioning point mutations in a woolly mammoth from Wrangel Island with a low Ne compared with an older sample from a larger population. This suggests that genetic erosion played a significant role in the extinction of woolly mammoths on the island and demonstrates its importance in conservation.
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Excerpt: "They found that threatened species had reduced genetic variation, likely due to inbreeding and the random loss of variation that occurs when population sizes are small.
The team then examined IUCN’s criteria for classifying threatened species to determine how effective the criteria were at identifying genetically poor species. If genetic diversity estimates correlated with the Red List criteria, then IUCN would be systematically selecting for populations or species that have declining diversity, the researchers reasoned. Unexpectedly, they found that IUCN’s criteria were not closely linked to genetic diversity.

“Unless a population with poor genetic diversity has undergone a dramatic decrease in size, it could be overlooked with our current methodology,” Willoughby says. “We should consider genetic diversity in conservation rankings so a species doesn’t go extinct simply because it wasn’t on our radar.” "


My comment: There are several examples of genetic erosion:

68,000 bacterial generations prove: EVOLUTION IS NOT HAPPENING
- No evolution but extremely rapid human genetic degradation
Genetic degradation - Carnivores lack taste for sweets
- Rapid genetic degradation refutes evolutionary fairytales
- Genetic meltdown just in five generations
- How a broken gene accelerates genetic erosion
- A typical example of genetic erosion
- No random beneficial mutations but a huge number of genetic maladies
- Organisms need genetic rescue
- Genetic degradation - About 40,000 species become extinct every year

Mechanisms for genetic erosion are already well understood. Changing epigenetic information profiles typically result in gradual but inevitable genetic errors. Evolution is a myth. Don't get lost.


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