Epigenetic Changes, Not Mutations, Cause Mexican Cave Fish Lose Their Eyesight

Image courtesy of Johnston DJ, CC BY-SA 3.0.


Joel Kontinen

Mutations do not explain why some Mexican cave fish (Astyanax mexicanus) have lost their eyesight.

New Scientist reports on recent research of these fish:

"Aniket Gore of the US’s National Institute of Child Health and Human Development and colleagues haven’t found any disabling changes in the DNA sequences of eye development genes in the cavefish.

Instead, the genes have been switched off by the addition of chemical tags called methyl groups. This is what is known as an epigenetic, rather than genetic, change.”

It would not be honest to call this Darwinian evolution, as it isn't.

New Scientist calls it an unexpected evolutionary process, but it would be more appropriate to call it a non-evolutionary process or a non-Darwinian process.

The fish did change, they lost a feature they had (eyesight), but the cause of their adaptation to darkness is anything but Darwinian.

Source:

Le Page,Michael. 2017. Blind cave fish lost eyes by unexpected evolutionary process. New Scientist (12 October).

Are City Mice Evolving to Eat Pizza – Or Do News Outlets Use the E-word Misleadingly?

John Tenniel, 1871: Humpty Dumpty from Through the Looking Glass, public domain.




Joel Kontinen

"When I use a word," Humpty Dumpty said, in rather a scornful tone, "it means just what I choose it to mean—neither more nor less."

A lot of water has flown in the world’s rivers since Lewis Carroll penned those words in 1872, but at least in some respects there is little if anything completely new under the sun.

Take the word evolution, for instance. A few weeks ago, New Scientist suggested that losing eyesight was 'regressive evolution'.

More recently, the magazine proposed that rats living in New York City might be evolving to eat pizza.

However, some animals are opportunistic: they eat what they can find. They are adapting to city life, but this doesn’t have anything to do with Darwinian (molecules-to-mice) evolution.

Sources:

Baraniuk, Chris. 2017. New York City mice may be evolving to eat fast food like pizza. New Scientist (4 October).

Knowles, Elizabeth. (ed). 2004. Oxford Dictionary of Quotations. Oxford: Oxford University Press.

Sea Snakes Replay Peppered Moth Story

Some sea snakes, such as the Blue-lipped sea krait, Laticauda laticaudata, have not turned black. Image courtesy of Jon Hanson, CC-BY-SA-2.0.





Joel Kontinen

The peppered moth (Biston betularia) is one of the most famous icons of evolution, together with Darwin’s finches.

These icons share a common trait: tiny changes that didn’t last very long.

Now, a paper published in the journal Current Biology features another case of industrial melanism.

Rick Shine at the University of Sydney and colleagues found that the turtle-headed sea snake (Emydocephalus annulatus) is turning black due to pollution.

Reporting on the story, New Scientist says:

“The group already knew that pollutants such as arsenic or lead can bind to melanin, a dark pigment in the skin, and they wondered whether this might explain the black snakes. To find out, they collected and analysed the skins naturally shed by these snakes in industrial and non-industrial waters. The sea snakes typically shed – or slough – their skin a few times a year.”

The NS story goes on to say:

“Looking at 17 sloughs, Shine’s group found that the concentrations of 13 trace elements – particularly cobalt, manganese, lead, zinc and nickel – were higher in snakes near urban areas, and higher in darker skin. Shine says similar concentrations of those trace elements have been reported to cause severe health problems in many domesticated species, from cattle to poultry.

What’s more, Shine’s group found that the black sea snakes shed their skins twice as often as their lighter counterparts. This suggests that the black sea snakes are, indeed, adapting to deal with the pollution in the water they inhabit – both by developing skin with a better capacity to bind potentially harmful trace elements, and by shedding that skin more often to reduce the trace element load they must deal with.”

Instead of invoking evolution, a more credible explanation would rely on design. Sea snakes were designed with the ability to survive in hazardous environments.

This reminds us of the ability of many animal species to adapt to new challenging environments after the year-long global flood of Noah’s days.

Source:

Woodward, Aylin. Sea snakes are turning black in response to industrial pollution. New Scientist (10 August).

Scientific American: humans are still evolving

Evolutionists do not agree on whether humans are still evolving. Image courtesy of José-Manuel Benito Álvarez, Wikipedia.




Joel Kontinen

At times, there are interesting twists and turns in the discussion on evolution. Two years ago Steve Jones, professor of genetics at University College London, announced that human evolution was over.

Recently, however, Scientific American published an article that suggests that professor Jones might have been a bit hasty with his pronouncement. Just ask the Tibetans who have continued their evolution by adapting to living at a high altitude.

Tibetans have not ceased to be H. sapiens. According to the article they have managed to overcome altitude sickness and other problems resulting from a low level of oxygen with the help of evolution.

Scientific American might have forgotten to tell its readers that the changes wrought in the Tibetans do not have anything to do with Darwinian evolution but they reveal that humans were designed to adapt to various climates and circumstances.

This ability speaks of very intelligent design.

Source:

Pritchard, Jonathan K. 2010. How We Are Evolving. Scientific American (22 September) http://www.scientificamerican.com/article.cfm?id=how-we-are-evolving&sc=WR_20100928.