UCLA biologists reveal potential ‘fatal flaw’ in iconic sexual selection study


A new sexual selection study replicates an iconic 1948 study and finds it flawed. The graphic shows that children of fruit fly parents with different mutations have an equal chance of inheriting just the mother’s mutation, just the father’s mutation, both mutations or neither mutation. (Credit: Kim DeRose)

A classic study from more than 60 years ago suggesting that males are more promiscuous and females more choosy in selecting mates may, in fact, be wrong, say life scientists who are the first to repeat the historic experiment using the same methods as the original.

In 1948, English geneticist Angus John Bateman published a study showing that male fruit flies gain an evolutionary advantage from having multiple mates, while their female counterparts do not. Bateman’s conclusions have informed and influenced an entire sub-field of evolutionary biology for decades.

“Bateman’s 1948 study is the most-cited experimental paper in sexual selection today because of its conclusions about how the number of mates influences fitness in males and females,” said Patricia Adair Gowaty, a distinguished professor of ecology and evolutionary biology at UCLA. “Yet despite its important status, the experiment has never been repeated with the methods that Bateman himself originally used, until now.

“Our team repeated Bateman’s experiment and found that what some accepted as bedrock may actually be quicksand. It is possible that Bateman’s paper should never have been published.”

Gowaty’s study was published June 11 in the online edition of Proceedings of the National Academy of Sciences and is scheduled for publication in an upcoming print edition.

Written By: Kim DeRose
continue to source article at phys.org


  1. I couldn’t help but get the sense that the criticism was at least as motivated by social expectations as the original study (if at all).

    Beyond that, there’s a fatal flaw in the main criticism.  Yes, relying on severe mutations will lower the number of traceable offspring.  That does not mean, however, that it will necessarily skew the results.  That would require that the female mutations were more harmful than the male mutations (or vice versa).  I did not see any indication that they tested this idea at all.

    It’s kind of ironic that a study criticizing the obviously flawed methods of an earlier study has its own obvious and significant problems.

  2. ” But Gowaty and her colleagues, by performing the same experiment, found that the data were decidedly inconclusive. “

    Aside from any other methodological flaws, as one mentioned by Thanny, we do not have a conclusion one way or the other. Dead flies can not be counted and such mutations as the article spoke of not noticed? 

  3. Just how choosy males are clearly varies by species. I offer as evidence the body of David Attenborough’s films.

    Different species make a different length commitment.  Sleepy lizards and many birds go for life. Humans go for about 7 years, other times 1 night. Frogs for 10 minutes.  I suspect choosiness increases with length of commitment.

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