Episode 197 – Brown Antechinus: Mating Marathon

“…and today we are literally talking about a creature that lives by a pattern of life and death and has an interesting taxonomy. But more on that later.” 

Every fall, the arid wilderness of Australia is peppered with the fallen bodies of tiny marsupials. What could create such a scene? Predators, disease, global warming? The answer is none of the above. The brown antechinus spends the month of August focused on one thing to the exclusion of all else, and it costs him his life.

In the immortal words of Obi-Wan Kenobi, he’s done that himself. But why such a sad ending for such a cute animal? Well, the answer can be found in this creature’s massive appetite, both for food and for love. But you gotta give it your all if you want to pass on your genes here in Life, Death, and Taxonomy.

Brown Antechinus Nicknames

  • Stuart’s Antechinus, Macleay’s Marsupial Mouse
  • Stuart Lottle
  • Mighty Mating Mouse Marsupial
  • Patrick Henry – Give me libido or give me death


  • Only the third species in its genus to be discovered. 
  • First described by William Sharp Macleay and named after his friend James Stuart.

Critter Groups 

What is the term of venery for Wombats?

  1. Wisdom
  2. Wallop
  3. Wilt
  4. Whimper

Description of the Brown Antechinus

  • At first glance, you’d swear this little marsupial was a mouse, or perhaps a shrew.
  • It has a perfectly pointed snout, big ears, a furry round body, and a long tail. 
  • It’s light brown with countershading.
  • Their feet are wide with thin fingers, which differs from a small slender mouse paw.  

Measure Up

Welcome to the beloved Measure Up segment. The official listener’s favorite part of the show! The part of the show when we present the animal’s size and dimension in relatable terms through a quiz that’s fun for the whole family. It’s also the part of the show that’s introduced by you when you send in audio of yourself saying, singing, or chittering the words Measure Up into ldtaxonomy at gmail dot com. We don’t have a new Measure Up intro!

  1. Crocodile
  2. Camel
  3. Pilot Whale
  4. Elephant

Body Length

  • 93–130 mm (3.7–5.1 in)
  • How many brown antechinuses go into the distance Harald Hel traveled across Australia on a mini scooter?
  • Hint: Harald went the distance on March 27, 2000, and it took him 18 days, 11 hours, and 25 minutes. He started in Port Augusta, South Australia, and ended in Darwin, Northern Territory.
  • 21,741,176 Antechinuses. The route was estimated to be 2,800 km (1,750 miles).


  • 16–44 grams (0.5–1.5 oz)
  • We’re talking about a small marsupial, but how many antechinuses go into one of the largest of the largest marsupials in the world?
  • Hint: The late Roger, the buff kangaroo, is a red kangaroo, making him bigger than all other marsupial species. We’ve talked about him before. In addition to being big, Roger was also an aggressive fighter. 
  • 2,061.7 marsupial mice. Roger was 200 pounds.

Fast Facts about the Brown Antechinus

The brown antechinus is native to the Southeastern parts of Australia. They like forests with a lot of dense foliage on the ground to provide them with cover. They also prefer forests that don’t burn that often. For two reasons: fire is hot and not good to touch and forest fires clear away ground cover. 

The fact that this mouse-like marsupial is not related to rodents is evidence that the mouse form is tried and true in nature. 

Unlike many subterranean mice, the antechinus is an arboreal aficionado. They come out at night to find spiders, beetles, crustaceans, and other insects to eat. Females share large communal nests.

While they have taken rodent-like features, they have also forsaken the marsupial in another key way: they don’t have a pouch. Instead, babies cling to their mothers and attach to the teet. 

Major Fact: Mating Marathon

Disclaimer for kids: This Major Fact involves mating habits and terms that not everyone may want to have to explain to their children just yet!

The antechinus is part of a group of animals that are semelparous – meaning they only mate once. While many insects, fish, mollusks, and even cephalopods do this, mammals are usually good to mate several times throughout their lives. So this little marsupial is an exception. Semelparity can refer to animals that mate once and continue living, but it usually tends to refer to suicidal reproduction.

The reason why mating only happens once with these guys is that their breeding season is insane.

Near the end of every July, all of the males completely stop producing sperm – meaning they have one chance to use it all up before they’re incapable of producing offspring.

For many animals, passing on one’s genes is the absolute top priority – even over, you know, living.

So the month of August is the only shot the males get to do what they were put on this earth to do. So in a frenzy, the males run around trying to mate with as many females as they can possibly find – or die trying.

A Taxing Trist

For weeks, a male’s body will be basically a tiny ball of stress hormones and testosterone, driving him to mate constantly. Each mating session is physically demanding and can last up to 14 hours.

He’ll stop eating, his fur will fall off, he’ll start bleeding internally, he’ll start metabolizing his muscles, his organs will start to shut down, and eventually, he’ll die.

So before they reach one year old, every male antechinus has boogied itself to death. Researchers thought that the males were being selfless and, having fulfilled their glorious purpose, sacrificed themselves to leave resources for their posterity. Others thought that females are easy prey after breeding, so mating with as many as possible hedges their bets.

The strongest theory seems to be their diet. Antechinuses mainly eat insects, which arrive in peak numbers called a bonanza. If the females have their young just before this bonanza, they and the young have the greatest chance of survival.

Joeys Hanging Out 

This is because they’re marsupials – not mice. So they give birth to severely underdeveloped joeys rather than the infants of other species. 

It takes four months of care to get a joey to the point where it doesn’t need its mother, so the females adapted to only mate right before the insect bonanza in the fall.

Therefore, the males evolved to maximize their mating potential during those few weeks in August when the females were receptive.

Rather than compete by fighting each other, as many other animals do, the antechinus competes by sheer volume – lots of notches on their bedposts and lipstick cases.

Ending: So pace yourself, take care of your physical and mental health, and indulge in moderation unlike the brown antechinus here in Life, Death, and Taxonomy.