Pages

▼

Sunday, 30 June 2024

Refuting Creationism - The Last Woolly Mammoths Were Dying Out Just As Creationism's God Was Allegedly Comitting Global Genocide.


Wrangle Island landscape
Last surviving woolly mammoths were inbred but not doomed to extinction | ScienceDaily

Just as creationism’s little god was creating a small flat planet with a dome over it in the Middle East and thinking it was the Universe, the last remaining mammoths were becoming isolated on Wrangle Island off the north coast of Siberia.

The cause was a rise in sea-level which isolated a small population of about 8 individuals, which grew to a stable population of about 200-300. They were to survive there for the next 6,000 and so were contemporaneous with early human civilisations such as the Egyptians and Sumerians.

Although there is no mention of them or any other species of elephant in the Bible, creationist dogma says there must have been two (or seven depending on version) and that all elephants have evolved by warp-speed evolution since, including the extinct mammoths and mastodons.

This recent addition to creationist dogma, which used to argue that there was no such thing as evolution, was invented to get round the manifest absurdity of a wooden boat containing two (or seven) of every extant and extinct species. The only problem is that this last remaining group of mammoths went extinct about 4,000 years ago, i.e., at about the time of the legendary genocidal flood, so couldn't have evolved from the survivors, warp-speed evolution or not.

Exactly why they became extinct is still something of a mystery but a recent study by a joint collaboration between the Swedish Museum of Natural History and Stockholm University, led by Love Dalén, an evolutionary geneticist, has shown that, although the population on Wrangler Island was highly inbred, that was probably not the cause.

The researchers have published their findings, open access, in the Cell Press journal Cell. According to information made available by Cell Press ahead of publication:

What information do you have on the mammoths of Wrangle Island, Siberia? The mammoths of Wrangel Island, located in the Arctic Ocean off the coast of Siberia, are notable for being among the last surviving populations of woolly mammoths. Here are some key points about them:
    ;
  1. Isolation and Survival: Wrangel Island's mammoth population became isolated from mainland Siberian populations due to rising sea levels at the end of the last Ice Age, around 10,000 years ago. This isolation allowed them to survive thousands of years longer than their mainland counterparts.
  2. Late Extinction: The mammoths on Wrangel Island survived until approximately 4,000 years ago, which means they coexisted with human civilizations such as the early Egyptians and the Sumerians. This makes Wrangel Island mammoths one of the last known populations of woolly mammoths.
  3. Genetic Bottleneck and Diversity: Genetic studies have shown that the Wrangel Island mammoths suffered from a genetic bottleneck, leading to reduced genetic diversity. This was due to their small, isolated population size. The genetic problems likely contributed to their eventual extinction.
  4. Environmental Changes and Human Impact: It is believed that a combination of environmental changes and possibly human hunting led to their extinction. Changes in climate could have affected their food sources, and human presence on the island might have increased the pressures on their survival.
  5. Physical Characteristics and Adaptations: Despite their isolation, Wrangel Island mammoths were similar in size and appearance to other woolly mammoths. However, some adaptations specific to the island's environment might have occurred, though these are less well-documented.
  6. Fossil Evidence and Research: Fossil remains and other evidence from Wrangel Island have provided significant insights into the life and extinction of these late-surviving mammoths. Studies of these remains have helped scientists understand more about mammoth genetics, their adaptations to cold environments, and the factors leading to their extinction.

Overall, the Wrangel Island mammoths represent a fascinating chapter in the history of these iconic Ice Age giants, highlighting how isolated populations can persist long after their species has largely disappeared elsewhere.
The last population of woolly mammoths was isolated on Wrangel Island off the coast of Siberia 10,000 years ago, when sea levels rose and cut the mountainous island off from the mainland. A new genomic analysis reveals that the isolated mammoths, who lived on the island for the subsequent 6,000 years, originated from at most 8 individuals but grew to 200-300 individuals within 20 generations. The researchers report June 27 in the journal Cell that the Wrangel Island mammoths' genomes showed signs of inbreeding and low genetic diversity but not to the extent that it can explain their ultimate (and mysterious) extinction.

We can now confidently reject the idea that the population was simply too small and that they were doomed to go extinct for genetic reasons. This means it was probably just some random event that killed them off, and if that random event hadn't happened, then we would still have mammoths today.

Love Dalén, co-corresponding author
Centre for Palaeogenetics
Stockholm, Sweden.


In addition to shedding light on woolly mammoth population dynamics, this analysis of Wrangel Island mammoths could help inform conservation strategies for present-day endangered animals.

Mammoths are an excellent system for understanding the ongoing biodiversity crisis and what happens from a genetic point of view when a species goes through a population bottleneck because they mirror the fate of a lot of present-day populations.

Marianne Dehasque, co-corresponding author
Centre for Palaeogenetics
Stockholm, Sweden.


To understand the genomic consequences of the Wrangel Island bottleneck on the mammoth population, the team analyzed the genomes of 21 woolly mammoths -- 14 from Wrangel Island, and 7 from the mainland population that predated the bottleneck. Altogether, the samples spanned the last 50,000 years of the woolly mammoth's existence, providing a window into how mammoth genetic diversity changed through time.

Compared to their mainland ancestors, the Wrangel Island mammoth genomes showed signs of inbreeding and low genetic diversity. In addition to overall low genetic diversity, they showed reduced diversity in the major histocompatibility complex, a group of genes known to play a critical role in the vertebrate immune response.

The researchers showed that the population's genetic diversity continued to decline throughout the 6,000 years that the mammoths inhabited Wrangel Island, though at a very slow pace, suggesting that the population size was stable up until the very end. And although the island's mammoth population gradually accumulated moderately harmful mutations throughout its 6,000-year tenure, the researchers showed that the population was slowly purging the most harmful mutations.

If an individual has an extremely harmful mutation, it's basically not viable, so those mutations gradually disappeared from the population over time, but on the other hand, we see that the mammoths were accumulating mildly harmful mutations almost up until they went extinct. It's important for present day conservation programs to keep in mind that it's not enough to get the population up to a decent size again; you also have to actively and genetically monitor it because these genomic effects can last for over 6,000 years.

>Marianne Dehasque.
Though the mammoth genomes analyzed in this study straddle a large timespan, they do not include the final 300 years of the species' existence. However, the researchers have unearthed fossils from the mammoth's final period and plan to conduct genomic sequencing in the future.

What happened at the end is a bit of a mystery still -- we don't know why they went extinct after having been more or less fine for 6,000 years, but we think it was something sudden. I would say there is still hope to figure out why they went extinct, but no promises.Love Dalén

Highlights
  • Analysis of long-term genomic changes using 21 high-coverage woolly mammoth genomes
  • Severe bottleneck of the last surviving population when Wrangel Island was isolated
  • The population partially recovered within a few generations and then remained stable
  • Inbreeding depression and purging persisted for thousands of years after the recovery

Summary
A number of species have recently recovered from near-extinction. Although these species have avoided the immediate extinction threat, their long-term viability remains precarious due to the potential genetic consequences of population declines, which are poorly understood on a timescale beyond a few generations. Woolly mammoths (Mammuthus primigenius) became isolated on Wrangel Island around 10,000 years ago and persisted for over 200 generations before becoming extinct around 4,000 years ago. To study the evolutionary processes leading up to the mammoths’ extinction, we analyzed 21 Siberian woolly mammoth genomes. Our results show that the population recovered quickly from a severe bottleneck and remained demographically stable during the ensuing six millennia. We find that mildly deleterious mutations gradually accumulated, whereas highly deleterious mutations were purged, suggesting ongoing inbreeding depression that lasted for hundreds of generations. The time-lag between demographic and genetic recovery has wide-ranging implications for conservation management of recently bottlenecked populations.
Graphical abstract
Introduction
Over the past centuries, many species around the world have come close to extinction.1 Although some of these species have made partial recoveries in population size,2,3,4,5 it is unlikely that they will fully recover due to ongoing habitat losses. From a genetic standpoint, it is therefore important to understand how severe bottlenecks followed by partial demographic recoveries will affect future extinction risks. In small populations, genetic factors are expected to play an increasingly important role for their long-term viability.6,7 To understand to what extent genetic processes contribute to extinction risk in small populations, time-series data over a wide temporal range can provide valuable insights. Yet, many studies focusing on the genetic burden in endangered species have been limited to data comprising one or a few generations since the population’s decline,4,8,9,10 making it difficult to distinguish between the initial genetic consequences of the rapid population decline and long-term inbreeding depression as well as the possible accumulation of deleterious mutations.11,12,13

The woolly mammoth (Mammuthus primigenius) is an excellent model system to investigate the genetic consequences of a severe bottleneck followed by long-term small population size. It became extinct across most of its range at the end of the Pleistocene, although isolated populations survived into the Holocene.14,15,16 The population on Wrangel Island, a small island north of mainland north-eastern Siberia, went through a bottleneck event when mammoths became isolated there in the early Holocene around 10,000 years ago due to rising global sea levels at the start of the Holocene.17,18,19,20 The Wrangel Island mammoths subsequently survived as a small population for hundreds of generations, before eventually becoming extinct about 4,000 years ago.20,21,22 The availability of well-preserved remains spanning several thousands of years before and after the mammoths’ isolation on Wrangel Island provides the opportunity to investigate evolution in a bottlenecked and isolated population in real time.

Dehasque, Marianne; Morales, Hernán E.; Díez-del-Molino, et al
Temporal dynamics of woolly mammoth genome erosion prior to extinction
Cell (2024). DOI: 10.1016/j.cell.2024.05.033

Copyright: © 2024 The authors.
Published by Cell Press. Open access.
Reprinted under a Creative Commons Attribution 4.0 International license (CC BY 4.0)


So, a question for creationists, then:
How is it possible for the last mammoths on a Siberian island to go extinct at the same time as your legendary genocidal flood, if all the elephant family, including the extinct species, are descended from two (or seven) descendants of survivors of a flood that was only just happening? And why were the authors of the flood myth apparently unaware of elephants, which would have needed several tons of fodder every week to sustain them and would have produced mountains of excrement to be disposed of?

Like dinosaurs and other extinct animals, elephants don't rate a mention in the Bible!
Advertisement

What Makes You So Special? From The Big Bang To You

How did you come to be here, now? This books takes you from the Big Bang to the evolution of modern humans and the history of human cultures, showing that science is an adventure of discovery and a source of limitless wonder, giving us richer and more rewarding appreciation of the phenomenal privilege of merely being alive and able to begin to understand it all.

Available in Hardcover, Paperback or ebook for Kindle

Advertisement

Ten Reasons To Lose Faith: And Why You Are Better Off Without It

This book explains why faith is a fallacy and serves no useful purpose other than providing an excuse for pretending to know things that are unknown. It also explains how losing faith liberates former sufferers from fear, delusion and the control of others, freeing them to see the world in a different light, to recognise the injustices that religions cause and to accept people for who they are, not which group they happened to be born in. A society based on atheist, Humanist principles would be a less divided, more inclusive, more peaceful society and one more appreciative of the one opportunity that life gives us to enjoy and wonder at the world we live in.

Available in Hardcover, Paperback or ebook for Kindle


Advertisement



Thank you for sharing!







submit to reddit
at

No comments:

Post a Comment

Obscene, threatening or obnoxious messages, preaching, abuse and spam will be removed, as will anything by known Internet trolls and stalkers, by known sock-puppet accounts and anything not connected with the post,

A claim made without evidence can be dismissed without evidence. Remember: your opinion is not an established fact unless corroborated.