Researchers find evidence of independent evolution of female penis in cave insects

**Researchers find evidence of independent evolution of female penis in cave insects
(a) Neotrogla sp. in copula. (b) Terminal abdomen of N. curvata in copula. Female structures are highlighted by red. (a–l) Morphology of the female (c–i,k) and male ( j,l ) genitalia in Sensitibillini, with the homology scheme indicated by colours. (c,i–j) Neotrogla truncata. (d) N. curvata. (e–f,k – l) N. aurora (note that N. brasiliensis and N. sp. also have this type of genitalia). (g) Sensitibilla etosha. (h) Afrotrogla oryx. Dotted regions of illustrations indicate membranes and others are sclerite ((c–h): approximately to scale). Arrowheads in (c–h) indicate the opening of the spermathecal duct, and arrowheads in ( j) and (l ) indicate the presence (filled) or the absence (open) of male vaginal pouches. (c–e) Lateral view; (f–i,k) ventral view; ( j,l ) dorsal view. Credit: Biology Letters (2018). DOI: 10.1098/rsbl.2018.0533

A team of researchers from Japan, Brazil and Switzerland has found evidence that suggests female penis-like appendages in two types of cave insects evolved independently. In their paper published in the journal Biology Letters, the group describes their study of Sensitibillini insects and what they discovered.

Four years ago, a team of researchers from Japan discovered a genus of insect living in a in Brazil with females that had penis-like appendages and males with vagina-like pouches. The insects were given the name Neotrogla. Researchers noted that only one other insect had similarly reversed sexual organs, one named Afrotrogla. The two fell within the same genera, so the researchers with this new effort wondered if the reversed organs developed just once, before the two species diverged, or if they evolved independently. They noted that there was another closely related genus called Sensibilia, but its sex organs were not reversed. They then studied the sex organs of all three very carefully, and came to the conclusion that the reversed organs in the two species evolved independently.

Once the researchers came to this conclusion, they focused their attention on why it happened—it seemed quite coincidental, considering that just about every other known has the more familiar male penile appendage. After comparing the environments in which the two species evolved and continue to live, they suggest it likely came down to competition for . Both live in caves where food is scarce. Because of that, males appear to be more interested in finding food than in mating. This has led the females to assume the role of pursuer and initiator. And to prevent the male from escaping before his sperm has been collected, the female has evolved a hook that latches onto the male, keeping him in place for two or three days.

The researchers note that there are many examples of and evolving in tandem to accommodate the transfer of sperm, but none compare to the unique anatomy of the Sensitibillini. They also suspect that predation in their environments likely played a role in the development of their sex organs as well.

Explore further

In sex-reversed cave insects, females have the penises

More information: Kazunori Yoshizawa et al. Independent origins of female penis and its coevolution with male vagina in cave insects (Psocodea: Prionoglarididae), Biology Letters (2018). DOI: 10.1098/rsbl.2018.0533
Journal information: Biology Letters

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Citation: Researchers find evidence of independent evolution of female penis in cave insects (2018, November 21) retrieved 22 August 2019 from
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Nov 22, 2018
I thought that now study the male penis. After all, Viagra was invented ( ), but it has contraindications. U must go to the doctor. When will come up with Viagra without side effects

Nov 22, 2018

Nov 22, 2018
Among other things, food scarcity may not be part of any explanation. It's reasonable that males and females would be equally as interested in food, so there should not be any special emphasis for each that would lead them to this.
Too, as is so often the case with "evolutionists", they simply say that something fits a situation. They don't think that "evolution", as described, does not assess a situation, then design something to accommodate! "Evolution" is described with working with what it has available. Introducing something wholly new can be questionable.
Also, as is the case in so many situations, "evolution" takes a long time and, if food is scarce for the creature's supposed previous form, how could the species survive long enough to "evolve"?

Nov 23, 2018
so, julia (how can anyone be certain?).

You are back to blaming all the genetic chaos and the cacophony of randombunctuous sexual reproduction on the drunken buffoonery of incompetent deities?

Hey, works for me!

Yeah, I know, that answer is going to piss off the deity. However it is too be expected that an infantile deity will piss a whole lot! Imagine how many diapers a 13+ billion year old baby has gone through...

Nov 27, 2018
The conclusions reached in this research are irrational.

Given the actual observed evidence, it is not possible to get to their conclusion of things having "evolved" with the GOALS pursued by the female insects.

How do they reconcile the supposed blind and purposeless evolutionary purpose with their implied design purposes to reach that specific goal? It is irrational to attempt to do so and still cling to a purposeless process. They are attributing intelligence to what is supposed to be a random walk in the dark. This is irrationality personified.

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