One 400 million - year - oldtrilobitespecimen has revealed new insights into the phylogenesis of sexual combat weapons system . The trilobite ’s trident , typically a three - pronged ramification that was thought to be used for feeding , had four prongs , leading investigator to think that it develop for fighting , not feeding .
“ The extraordinary Devonian trilobiteWalliseropscarried a unique , elephantine trident on its head teacher , the design of which has long been a whodunit , ” said Prof Richard Fortey FRS , Scientific Associate at the Natural History Museum London and Centennial State - author of a new newspaper publisher in a statement sent to IFLScience . “ We now believe that it was used for ‘ jousting ’ between male striving for dominance . ”
The trilobite dodo is aWalliserops trifurcatusspecimen that had produce to full maturity and grownup size of it before it died and became a part of thefossilrecord . It had a malformed trident equipped with four tines rather of three , but despite this was able to come through to adulthood .
A morphometric comparison of the trilobite’s trident revealed it shared similarities with the sexual combat weaponry of certain beetle species. Image credit: Alan D. Gishlick
If the trident was a all important dick for feeding , having a malformation would be expected to take to other death as the animal could n’t bung properly . Since this trilobite understandably fetch by just o.k. with its unique trident , researchers in the newfangled paper hypothesized that it might instead have been used in intimate fight .
Anatomical weaponry for fighting over potential spouse is widespread across the animal realm , but perhaps the most comparable in the case of trident - wielding trilobites arerhinoceros beetlesfrom the subfamilyDynastinae . As their name suggests , these arthropods have hooter - like protrusions on their nous which they practice for jousting competing male person in an effort to grade a mate .
The status and inflexibleness of theWalliseropstrident also seemed an unlikely fit for feeding setup , but a comparison of its trident against the lowly intimate characteristic of comparable life coinage withinDynastinaerevealed similarity . It seems the trident ofWalliseropstrilobites would ’ve been in just the correct position for agitate over females , which could explain how our malformed four - tined - trident specimen was able-bodied to thrive despite having a less conventional snatch of outfit on its head .
With the morphometric psychoanalysis supporting the hypothesis that the trilobite ’s trident was used in sexual combat , Walliseropsbecomes the oldest know example of sexual combat weaponry know to science .
“ The evolution of sexually motivated contender in animals is hundred of millions of age older than we thought , ” concluded Fortey .
The written report was published in the journalPNAS .
