Genetics speciation

It’s likely impossible to find out how many species there are

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But don’t tell Mother Jones’s readers:

The Census of Marine Life closing ceremony was meant to celebrate the fact that humans had, for the first time, estimated how many species there were in the sea. The Sloan Foundation, which partially funded the $650 million, 10-year project, organized the event. Scientists had been trying to uncover this magic number for at least 250 years. Previous estimates had put the number somewhere between three million and 100 million species on Earth—a nice way of saying they had no idea. But on this day, Mora and his team were supposed to unveil a much more specific conclusion.

Reporters swarmed the museum, hoping to get the scoop on the scientists’ discovery. The spokespersons for the scientists did the only thing they could do: regale the crowd with other findings, facts the researchers drummed up when they realized they couldn’t find the magic number they’d been looking for.

Mora himself considered the mystery “one of the most basic questions of biology” that was still unanswered. To be clear, it’s still unanswered: Mora, Worm, and their coauthors’ paper got us closer to a solid estimate. Scientists continue to learn more about the number of species on Earth every year. Ilana Strauss, “The Strange Story Behind Animals We Know We Haven’t Yet Discovered” at Mother Jones

Trichoplax adhaerens photograph.png
Trichoplax adhaerens/Berndt Schierwater et al. (CC by 4.0)

The critical difficulty is worse than the complexities laid out in the article. How do we even decide what a species is? See, for example, World’s simplest animals as different from each other as humans and mice: “A quarter of the genes were in the wrong spot or written backward. Instructions for similar proteins were spelled nearly 30 percent differently on average, and in some cases as much as 80 percent. The Hong Kong variety was missing 4 percent of its distant cousin’s genes and had its own share of genes unique to itself. Overall, the Hong Kong placozoan genome was about as different from that of T. adhaerens as human DNA is from mouse DNA. ‘It was really striking,’ Eitel said. ‘They look the same, and we look completely different from mice.’” Yet countless species classifications are based on appearance (taxonomy) and not on genetics.

See also: A physicist looks at biology’s problem of “speciation” in humans

10 Replies to “It’s likely impossible to find out how many species there are

  1. 1
    daveS says:

    I wonder if it’s possible to count the number of dialects of languages spoken by humans. I suppose one could, but it would require that some arbitrary choices be made.

  2. 2
    PaoloV says:

    How many baramins?
    🙂

  3. 3
    daveS says:

    How many baramins?

    If it’s impossible to count species, I’m guessing counting baramins is impossible squared.

  4. 4
    polistra says:

    Can’t beat Boris Worm as a name for a marine ecologist.

  5. 5
    Peer says:

    The problem of species and baranims was solved in this book:

    https://www.amazon.co.uk/Darwin-Revisited-understand-biology-century/dp/6202315113

    It also solves the RNA virus paradox and provides a novel evolutionarz theory.

  6. 6
    daveS says:

    The problem of species and baranims was solved in this book:

    **

    It also solves the RNA virus paradox and provides a novel evolutionarz theory.

    *searches Peter Borger and Scholars’ Press*

    -_-

  7. 7
    daveS says:

    Hmm. “Peer” = “Peer Torberg”, an anagram for “Peter Borger”?

  8. 8

    DaveS and PaoloV, it should be clear that the # Baramins must be less than the # Species. As a start, I would suggest that #B = sqrt(#S). Then the uncertainty in the # species (dS) would map to baramins as: dB = sqrt(dS).

    So I’m essentially disagreeing with your assertion that dB = dS^2.

    In any case, baramins fail to solve the “Ark problem”, however I have a recent book that solves it much more neatly. The Long Ascent: Genesis 1-11 in Science and Myth, vol 1. http://www.amazon.com/Long-Asc.....B0757FXX2S

  9. 9
    PaoloV says:

    Robert Sheldon,

    Thanks for the information.

  10. 10
    jdk says:

    I believe that if B = sqrt (S) = S ^ (1/2), then dB = 1 / (2 sqrt (S)) * ds

    It is certainly NOT the case that if B = sqrt (S), then db = sqrt (ds). Am I missing something, or do we have an elementary calculus mistake in 8?

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