Tegu necrophilia
March 2, 2015

Are lizards necrophiliacs?

Brett Smith for redOrbit.com - @ParkstBrett

Necrophilia might be one of the last remaining taboos in our society, but for some male Brazilian lizards, a dead female lizard doesn’t mean she’s not DTF.

Zoologist Ivan Sazima first observed the behavior while on a nature walk in search of interesting animal interactions. What he probably didn’t expect to find was a male black-and-white tegu getting his freak on with a long-deceased female companion.

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"I felt a sense of wonder, because I did not observe this behavior in lizards before, only in frogs," Sazima, from the Zoology Museum of the University of Campinas in São Paulo, told National Geographic.

This ain't their first rodeo

To be clear, necrophilia has been seen in some lizard species before, but not in Salvator merianae, the lizard’s scientific name which doubles as a a future 50 Shades of Grey character.

Sazima said he looked on as the male tegu started the courtship ritual by flicking his tongue at the unresponsive female. He then proceeded to mate with the female for around 5 minutes. A gaggle of geese then happened upon the scene – sending the copulating male running for the underbrush.

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Sazima said he returned to the scene the next day and found that the female’s corpse had begun to rot and stink. However, this state of decomposition didn’t prevent a different male from going at the corpse: This time for nearly an hour.

During the marathon necrophilia session, the male lizard bit the rotting, stinking corpse on the head – another classic mating behavior. Occasionally, he rested atop his decomposing companion between bouts of copulation. Finally, he finished by flicking his tongue on the corpse and rambling off.

Again, this ain't their first rodeo...but why?

Sazima’s observations, in September 2013, are just two in a long list of lizard necrophilia records. Henrique Caldeira Costa, of the Federal University of Minas Gerais in Brazil, reported in 2010 a necrophilia incident involving a female ameiva lizard that appeared to have been hit by a car.

Despite all these records of this activity, "necrophilia in lizards is still poorly understood," Costa told Nat Geo.

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Sazima argued that the black-and-white tegus simply aren’t capable of knowing a female is dead and they simply see her as receptive to their amorous advances. If the body is still warm and releasing pheromones, the male tegus probably can’t help themselves, he said.

Costa agrees with this theory, and said the incident he observed in 2010 was probably driven by the female's high body temperature and pheromones leaking from her crushed corpse.

Reasonable necrophilia

While humans might have a tough argument in defending acts of necrophilia for our own species, one form of necrophilia found in the animal kingdom can actually be defended. A small frog, also from Brazil, called Rhinella proboscidea practices “functional necrophilia,” in which males can extract eggs from dead sexual partners and fertilize them.

Not exactly romantic, but it does serve a purpose.

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