When I wrote Nature’s Nether Regions, I struggled a lot with sperm and ova. Should I include the evolution of sex cells (or “gametes”) in the book or not? In the end, I did so, but only minimally. After all, the evolution of the multitude of shapes and traits, forms and functions of sperm cells and egg cells is a mer à boire just as complex as that of genital organs themselves. All the sexual selection forces that mold the shape of penises and vaginas do their tricks all over again when confronted with the cells that are channelled by these genitals.
A new article in this week’s PLoS Biology gives us a peek into the amazing world of gamete evolution. Janice Ting of the University of Toronto and co-authors studied that workhorse of developmental biologists, the tiny nematode worm Caenorhabditis. They discovered that, when they tried crossing one Caenorhabditis species with another, not ony did they not get any offspring, but also the female would be the worse for wear afterwards: she often died shortly after the deed. As it turned out, this was due to the sperm cells she had received from the other species’ male. Ting and colleagues saw how these had broken out of the uterus and were wreaking havoc with the female’s internal organs.
The reason probably is that that worm species with such rogue sperm was a sexually reproducing one, whose sperm has been continuously evolving to outcompete other males’ sperm (with the female reproductive system keeping up, evolutionarily, by bolstering the organ walls and the like). The species to which the hapless female belonged, however, was a species that mostly reproduced as a hermaphrodite (that is, it is male and female at the same time), by self-fertilizing–in nematodes evolution causes repeated shifts between sexual and hermaphroditic species. Since in such species there is not so much competition among the sperm of different males, these species have not been adapted to withstand the onslaught of aggressive sperm cells.
If true, then this is an interesting new reason why different species often have reproductive barriers: they cannot cross-breed because their female reproductive system cannot cope with the aggressive sperm cells of the other species. In one of my previous books, Frogs, Flies & Dandelions, I describe how female tsetse flies sometimes die after mating with a male from a different part of Africa because their vaginas are simply ripped apart by those males’ genitals. This new worm study again shows how barriers between species may evolve simply because sexual strategies do not keep up with one another.
Bill Eberhard has been a prolific and very influential scientist publishing widely on anything to do with sexual evolution. His books Sexual Selection and Animal Genitalia and Female Control have been cited by other authors (usually a good proxy for academic impact) thousands of times. But one of his articles has, in the more than twenty years since it was published, received no attention whatsoever. In 1991, he wrote a short paper for the journal Medical Hypotheses in which he argued that artificial insemination effectivity in women could be improved if the pipette used were, well, dildo-shaped and applied with gusto, rather than clinical sobriety. Granted, he does not say it in so many words, but statements like, “the male genitalia of humans perform complex movements and change form during ejaculation. It seems unlikely that such complex and consistent behavior is bereft of reproductive significance” leave little to the imagination. What Eberhard basically says is, if artificial insemination were accompanied with the kind of stimulation that comes with regular intercourse, chances are that it will be more successful.
Eberhard has good reasons to think so. In livestock, assisted pregnancy procedures routinely make use of such erotic aids. Swine insemination uses a boar penis shaped pipette–to good effect. Likewise, lab mice are often artificially inseminated while undergoing simulated mating with a vaginal tampon or an artificial mouse penis. And in rats, bigger litters are produced after artificial insemination if a (small-sized) vibrator is applied to the female during the insemination procedure. All this suggests that the penis and its movements perform an “internal courtship,” which, if it pleases the female, results in her absorbing, storing, and/or using more sperm. And why not give this a try in human assisted conception as well?
More recently, another curious scientific paper shows benefits from a whole different kind of theatre. In a 2011 article in the journal Fertility and Sterility with the intriguing title, “The effect of medical clowning on pregnancy rates after in vitro fertilization and embryo transfer”, a team of Isreali authors show that IVF was 16% more effective in a group of women who had witnessed a medical clown performing shortly after their IVF treatment. As the medical researchers write, “Each patient in [this] group was visited by a professional medical clown immediately after [embryo transfer], while lying in bed. This encounter lasted 12–15 minutes and included a routine developed by the principal investigators (SF and AS) as suitable for such patients. The routine included jokes, tricks, and magic and was performed on a one-to-one basis with the clown dressed as a ‘‘chef de cuisine.’’ The same clown performed the same routine at all visits.” The clown in question was Mr. Shlomi Algussi, who may be seen performing in this video:
We assume the encounters were monitored by the researchers, so that the 16% extra conception rate cannot be due to some unauthorized “tricks” on the part of the clown.
It took a little effort, but I resisted the temptation to quip about blue velvet worms when I chatted with Isabella Rossellini last night. The Holland Festival had permitted me, my Dutch publisher, and my son, to spend a little time with her during the after-party following on the Dutch premiere of Bestiaire d’Amour, her stage show inspired on her Green Porno short films (see earlier blog post).
I had read mixed reviews of the show, but was not disappointed. Far from it: it was accurate and up-to-date sexual selection theory presented with Hollywood glamour and slapstick humor thrown in. The biological accuracy is not surprising, since Rossellini is doing a Master’s degree in animal behaviour, which, she told me, she can only work on for a few weeks each summer. She confided that she has an ongoing battle with her manager who tries to get her to go on tours when she should really be taking exams — a problem that not many behavioral biology students face.
I presented her with a copy of Nature’s Nether Regions, as well as its Dutch and Italian translations (the title of the latter, Anche le Coccinelle Nel Loro Piccolo, she translated for lookers-on). She said it was a “very nice book”, and promised to “read it on the plane”.
We were not permitted to take any photos, so you’ll have to take my word for it that you’re now just a mouseclick plus a handshake removed from the Queen of Animal Sex.
Tickets for the 20 and 21 June shows are still available.
Dear readers, ever wanted to ask me direct questions about me, my book, or anything you’ve always wanted to know about genitals but were afraid to ask? Today, 11th June, 2pm ET, I’ll be online at Reddit to do an AMA (Ask Me Anything). Just check Reddit’s AMA page and look for me.
And here is the full transcript of the questions and answers.
On the first page of Nature’s Nether Regions, I applaud Isabella Rossellini and her Sundance Channel series of “Green Porno” shorts, in which she re-enacts the copulation of many a wild animal. Rossellini is pursuing a master’s degree in animal behavior at Hunter’s College. So no suprise that the short films are accurate, uninhibited, and a perfect illustration of the diversity of reproduction in nature. That’s why I am so thrilled that the stage version of Green Porno, titled, for the European tour, Bestiaire d’Amour, will be coming to Amsterdam this month. As an event in the Holland Festival, the show will be performed three times, on June 19th, 20th, and 21st at the Stadsschouwburg. Here is one of the Green Porno videos, excerpts of which form part of Bestiaire d’Amour.
Tickets for the show may be ordered via the Holland Festival site.
Kees Moeliker, chief of the European Bureau of the Annals of Improbable Research, holds up Nature’s Nether Regions at Dead Duck Day 2014 (normally he holds up the duck). Photo by Anjes Gesink.
Nature’s Nether Regions last week featured at the 19th Dead Duck Day in Rotterdam. While the Dutch book launch was going on in Leiden, Kees Moeliker, Ig Nobel Prize winner and European director of the Ig Nobel Bureau (also curator at the Rotterdam Natural History Museum) was, as usual on this date, master of ceremonies at the annual Dead Duck Day in Rotterdam. This event, to commemorate the duck whose death and subsequent defilement is described on pp. 125-126 of Nature’s Nether Regions, takes place each year at the exact site where said duck flew against the museum facade, and highlights both animal misbehavior and the plight of birds colliding with buildings. This year, Dr. Moeliker mentioned the appearance of Nature’s Nether Regions and the role played in it by the dead duck (specimen NMR 9989-00232) lying in front of him. Rumor has it that next year’s 20th Dead Duck Day will feature a reading from the book…
Last night, Naturalis Biodiversity Center in Leiden hosted the launch of the Dutch version of Nature’s Nether Regions, entitled Darwins Peepshow, published by Atlas Contact in Amsterdam. It was a memorable event. The book was presented to Pek van Andel, Ig Nobel prize winning “penetration expert” famed for having been the first person to have studied human intercourse with MRI-scanning. Other notable attendees were Dutch science writers Midas Dekkers and Salomon Kroonenberg, the book’s illustrator Jaap Vermeulen, as well as many of the scientists whose work is featured in the book. Also present was Redmond O’Hanlon, the inimitable scholar and science and travel writer, author of such classics as Into The Heart of Borneo and In Trouble Again.
Our living link with the Victorian era: Redmond O’Hanlon.
The evening program, in the series “Naturalis After Dark” was sold out: 130 guests saw a vaudeville show consisting of videos, interviews, lectures, and discussions around the theme of human and animal sex and genitals.
A wonderful time was had by all.
Just a random moment from the Naturalis After Dark event “Nature’s Peep Show”
Ignobelist Pek van Andel receiving the first copy of Darwins Peepshow