A collection of sex-crazed maniacs

The time has come. The paperwork has been done; the preparations have been made. That's right: it's time to go get some study animals. Over the course of the next few months, our post-doc Amanda Niehaus and I (along with some fantastic volunteers) are starting to collect the animals my PhD will use, the yellow-footed Antechinus, Antechinus flavipes.

What a cutie. Image credit: Storm Martin.

If you don't know what an antechinus is, that's cool (you can see what they look like in the picture above) - they are fairly obscure animals that aren't all that well known even amongst the Aussies that share their habitat. Although they look like exceptionally pointy-faced mice, antechinus aren't rodents; they are members of the Dasyuridae, a family of small, carnivorous (usually insectivorous) marsupials. Some slightly better-known dasyurids include quolls and Tasmanian devils.

Unlike quolls and Tassie devils, antechinus are pretty tiny. Image credit: Storm Martin.

The antechinus' biggest claim to fame revolves around its wacky reproductive cycle. Unlike most mammals, antechinus are semelparous. That means that they invest all of their energy into one reproductive cycle and die shortly afterwards (unlike most other mammals, which are iteroparous, meaning that they reproduce multiple times throughout their life). The wacky component of all of this is that once the males reach reproductive maturity, they stop producing sperm; thus begins a frantic race to mate as many times as possible and spread their genes as far as they can before they die. Everything else gets shut down, and they literally breed until their bodies disintegrate. Sound extreme? Recent research has discovered that the reason for this frantically suicidal mating is probably due to intense sperm competition. In fact, both male and female antechinus are pretty friendly and like to cuddle up together at night, so there's actually little to no fighting going on at all. This makes them an awesome animal to work on, as their short life-cycle means that you can do multigenerational studies quite easily (and you can house them together).

Although they love to cuddle each other, antechinus aren't quite so fond of human handlers.

Although I'm still working out the specifics, my PhD is examining the effect of habitat structural complexity on performance, behaviour and overall fitness. Amongst other things, I'm looking at the effect the habitat complexity during development has on motor control and cognitive function in adults – for example, does exposure to a more complex habitat improve an animal's coordination as an adult? Does it improve its problem-solving abilities? These sorts of questions have applications well outside of the marsupial realm, so my results could be applicable to many other species. We're planning on establishing a breeding colony of semi-wild antechinus that we can raise in large, nature-simulating microcosms in order to investigate these questions.

Sunset at the Great Sandy National Park.

To collect our little darlings, we are travelling up north to the Great Sandy National Park near Cooloola, close to where a study by Geoffrey C. Smith identified a plentiful population back in 1984. Our first trapping trip took place last month, and while it took us a while to hit the right habitat (while it might sound specific, it turns out that "open sclerophyll with a complex understory" can actually apply to a wide range of habitats), we eventually managed to collect 12 antechinus of mixed sex.

Kuna, one of our little females. Image credit: Amanda Niehaus.

We caught other animals as well, including a few species of native rats. The bush rat, Rattus fuscipes, made frequent appearances and graced us with its delightful trap etiquette almost every day; any self-respecting rodent should know that the only acceptable way to behave when trapped in a small space with no way out is to defecate thoroughly and plentifully over every surface available. Anything else is pure barbarism. 

Despite their horrific smell, Rattus fuscipes are pretty dang cute.

We have at least a few more trips ahead of us before we'll have enough to start a breeding program to get our first set of babies to raise in controlled environments. Here's to hoping that this is the start of a beautiful (and productive!) friendship.

Smart, friendly (mostly) and completely adorable, not to mention sex lives that provide amazing party conversation fodder. Did I score? Heck yes! Image credit: Storm Martin.

All images by Rebecca Wheatley unless otherwise credited.