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Lager beer fermented by hybrid of genetically distant yeasts?

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From International Business Times (“Scientists Solve Lager Beer Mystery, Crack Yeast’s DNA Code”, August 23, 2011), we learn that cracking the DNA of the brewer’s yeast used to make lager revealed a hybrid “representing a marriage of species as evolutionarily separate as humans and chickens.” (Maybe so, but the technical difficulties attending a “chickman” are doubtless much greater.)

While scientists and brewers have long known that the yeast that gives beer the capacity to ferment at cold temperatures was a hybrid, only one player was known: Saccharomyces cerevisiae. Its partner, which conferred on beer the ability to ferment in the cold, remained a puzzle, as scientists were unable to find it among the 1,000 or so species of yeast known to science.

Now, researchers have identified the wild yeast that, in the age of sail, apparently traveled more than 7,000 miles to those Bavarian caves to make a fortuitous microbial match that today underpins the $250 billion-a-year lager beer industry.

It’s been named “Saccharomyces eubayanus.”

It would be interesting to know how often hybridization has been the actual source of new characteristics currently attributed to Darwinism.

For example, see also: “Spectacular” instance of interspecies mouse hybrids produces immunity to most poisons

3 Replies to “Lager beer fermented by hybrid of genetically distant yeasts?

  1. 1
    africangenesis says:

    “It would be interesting to know how often hybridization has been the actual source of new characteristics currently attributed to Darwinism.”

    It has often been hypothesized to be the source of variations. Horizontal gene transmission by plasmids in bacteria and by viruses in more complex organisms. Even before we had genetic evidence that hybridization of modern humans with neanderthal and homo erectus, alternatives to the out of Africa hypothesis had humans hybridizing ahd evolving in multiple places, most specifically in east Asia where characteristic skeletal differences seemed to persist across the transition to modern humans.

    Plants seem to have lower barriers to hybridization across the slipery category we call species.

  2. 2
    News says:

    The nice thing is, when you can establish how that happened, you can dispense with all the just-so storytellers in the Darwinian tradition, explaining why – at each successive stage of a long, slow, buildup of intricate machinery – the life form was just a tiny bit more fit. Rubbish. Horizontal transfer eliminates the fiction in favour of a simple criterion: Is the resulting hybrid viable in its environment?

    It also conforms to the picture of sudden appearances followed by long periods of stasis that we actually see: Successful hybrids don’t change much. They don’t need to, and maybe they can’t. How widespread HGT is is the next question.

  3. 3
    africangenesis says:

    Sexual reproduction itself can be thought of as hybridization, genes can be coming together with genes they’ve never been with before in the same organism. More likely than a continuing increase in fitness in a static environment, is the gradual buildup of variation ready to be screened by some new stress. What didn’t kill the dividing egg or embryo and still resulted in a viable organism, just made the species “stronger” in the sense of being ready for the next major selection events. Of course, it wasn’t so great for the individual organisms than had the “wrong” variations for whatever hit them next. Evolution is not a “personal” god, of course, some times even species don’t make it.

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