On the mountaintops of southeast Queensland in Australia, a group of marsupials known as dusky antechinus have some wild sex parties -- and researchers at the Queensland University of Technology (QUT) have just added two new species to the group.
During their yearly mating season, the males have sex with as many females as they can and then they die from the stress.
"The breeding period is basically two to three weeks of speed-mating, with testosterone-fueled males coupling with as many females as possible, for up to 14 hours at a time," researcher Andrew Baker said in a statement Monday. "Ultimately, the testosterone triggers a malfunction in the stress hormone shut-off switch; the resulting rise in stress hormones causes the males' immune systems to collapse and they all drop dead before the females give birth to a single baby."
Baker is a QUT mammalogist who, along with a team of researchers, described two new members of the antechinus group in the journal Memoirs of the Queensland Museum - Nature (PDF).
The scientists didn't so much discover the new species as reclassify them from under a broader taxonomic umbrella. The Tasman Peninsula dusky antechinus (A. vandycki) and the mainland dusky antechinus (A. mimetes) have been reclassified with species -- rather than subspecies -- status. To do so, the scientists used coloration and body measurements, especially openings in the palate known as palatal vacuities.
As you might imagine in an animal whose males all die after breeding, five of the 15 known species of antechinus are endangered, including the Tasman Peninsula variety, according to ABC. Adding to the perilous status of the animal is climate change and the destruction of habitats by logging, Baker says.
"These species have already retreated to their misty mountain summits -- in the face of ongoing climate warming, they have nowhere left to run," he said.
Baker and his team are working to conduct more research on the antechinus and have the three endangered species placed on Australia's federal threatened species list.