Top Stories Daily Listen Now
RawStory

Science

These fierce, tiny marsupials drop dead after lengthy sex fests

If you are exploring our beautiful Australian wilderness this year, keep an eye out for animals behaving in interesting ways. You never know what you might see, as our research team discovered.

In 2023, our colleague from Sunshine Coast Council, Elliot Bowerman, took a two-night trip to New England National Park – its 1,500 metre-high mountain peaks are some of the loftiest on Australia’s mid-east coast.

On the afternoon of 17 August, Elliot trekked the path to Point Lookout. While inspecting some plants on the trail, he heard a rustle in the bushes ahead and peering more closely, saw something of interest. A small mammal had abruptly appeared, dragging the carcass of another mammal, which it then began to devour.

At first glance, this was not so strange. Mammals eat each other all the time. However, it is unusual to see small mammals during the day at such close quarters, so Elliot recorded the scene, taking a video on his mobile phone.

It was only several days later when looking over the footage that our research team realised it featured something rarely seen in the wild, the record of which is now published in the journal Australian Mammalogy.

A native marsupial… cannibal

The furry critter on film was an antechinus, a native marsupial denizen of forested areas in eastern, south-western and northern Australia. Antechinuses usually eat a range of insects and spiders, occasionally taking small vertebrates such as birds, lizards, or even other mammals.

But this camera footage clearly showed a mainland dusky antechinus (Antechinus mimetes mimetes), and it was eating a dead member of its own species!

Antechinuses are perhaps best known for exhibiting semelparity, or “suicidal reproduction”. This is death after reproducing in a single breeding period. The phenomenon is known in a range of plants, invertebrates and vertebrates, but it is rare in mammals.

Each year, all antechinus males drop dead at the end of a one to three week breeding season, poisoned by their own raging hormones.

This is because the stress hormone cortisol rises during the breeding period. At the same time, surging testosterone from the super-sized testes in males causes a failure in the biological mechanism that mops up the cortisol. The flood of unbound cortisol results in systemic organ failure and the inevitable, gruesome death of every male.

A dark grey marsupial with a pointy snout tearing at pink flesh

A mainland dusky antechinus during the mating period, with fur loss visible on the shoulder, eating another antechinus. Elliot Bowerman

Mercifully, death occurs only after the males have unloaded their precious cargo of sperm, mating with as many promiscuous females as possible in marathon, energy-sapping sessions lasting up to 14 hours. The pregnant females are then responsible for ensuring the survival of the species.

So, exactly what was happening that day at Point Lookout – why had an antechinus turned cannibal?

Cheap calories

August is the breeding period for mainland dusky antechinuses at that location. Intense mating burns calories, and at the end of winter it is cold and there isn’t as much invertebrate food about.

If there are male antechinuses dropping dead from sex-fuelled exhaustion, our thinking is that still-living male and female antechinuses are taking advantage of the cheap energy boost via a hearty feast of a fallen comrade.

After all, animal flesh provides plenty of energetic bang for the buck, particularly if its owner does not have to be pursued or overpowered before being devoured.

In many areas of Australia, two antechinus species (of the known fifteen) occur together, and usually their breeding periods are separated by only a few weeks. One can imagine a scenario where individuals may not only feed on the carcasses of their own species but consume the other species as well.

An endangered silver-headed antechinus, Antechinus argentus. Andrew Baker

Each species may benefit from eating the dead males of the other. For the earlier-breeding species, females may be pregnant or lactating, which is a huge energy drain.

For the later-breeding species, both sexes need to pack on weight and body condition before their own breeding period commences.

Plausibly then, antechinus engage in orgiastic breeding and, when opportune, cannibalistic feeding.

So, the next time you are out and about in the bush, keep your eyes and ears peeled – you never know what secrets nature might reveal to you just around the next corner.

Keep reading... Show less

Research into holograms could improve forensic fingerprint analysis

When you use your fingerprint to unlock your smartphone, your phone is looking at a two-dimensional pattern to determine whether it’s the correct fingerprint before it unlocks for you. But the imprint your finger leaves on the surface of the button is actually a 3D structure called a fingermark.

Fingermarks are made up of tiny ridges of oil from your skin. Each ridge is only a few microns tall, or a few hundredths of the thickness of human hair.

Keep reading... Show less

‘Emergency’ or not, Covid is still killing people

With around 20,000 people dying of covid in the United States since the start of October, and tens of thousands more abroad, the covid pandemic clearly isn’t over. However, the crisis response is, since the World Health Organization and the Biden administration ended their declared health emergencies last year. Let’s not confuse the terms “pandemic” and “emergency.” As Abraar Karan, an infectious disease physician and researcher at Stanford University, said, “The pandemic is over until you are scrunched in bed, feeling terrible.” Pandemics are defined by neither time nor severity, but rather b...

First Turkish astronaut set for ISS mission, carrying Erdogan's space ambitions

When Turkey's first astronaut blasts off for the International Space Station (ISS) this week, he will embody his country's pride and President Recep Tayyip Erdogan's grand geopolitical ambitions.

Alper Gezeravci, a 43-year-old fighter pilot and colonel in Turkey's air force, was due to take off Wednesday from the Cape Canaveral Space Force Station in Florida for a two-week mission.

Keep reading... Show less

AI is learning to analyze chicken communications

Have you ever wondered what chickens are talking about? Chickens are quite the communicators — their clucks, squawks and purrs are not just random sounds but a complex language system. These sounds are their way of interacting with the world and expressing joy, fear and social cues to one another.

Like humans, the “language” of chickens varies with age, environment and surprisingly, domestication, giving us insights into their social structures and behaviours. Understanding these vocalizations can transform our approach to poultry farming, enhancing chicken welfare and quality of life.

Keep reading... Show less

How much life has ever existed on Earth?

All organisms are made of living cells. While it is difficult to pinpoint exactly when the first cells came to exist, geologists’ best estimates suggest at least as early as 3.8 billion years ago. But how much life has inhabited this planet since the first cell on Earth? And how much life will ever exist on Earth?

In our new study, published in Current Biology, my colleagues from the Weizmann Institute of Science and Smith College and I took aim at these big questions.

Keep reading... Show less

Your body already has a built-in weight loss system that works like Wegovy and Ozempic

Wegovy, Ozempic and Mounjaro are weight loss and diabetes drugs that have made quite a splash in health news. They target regulatory pathways involved in both obesity and diabetes and are widely considered breakthroughs for weight loss and blood sugar control.

But do these drugs point toward a root cause of metabolic disease? What inspired their development in the first place?

Keep reading... Show less

Why don’t fruit bats get diabetes?

People around the world eat too much sugar. When the body is unable to process sugar effectively, leading to excess glucose in the blood, this can result in diabetes. According to the World Health Organization, diabetes became the ninth leading cause of death in 2019.

Humans are not the only mammals that love sugar. Fruit bats do, too, eating up to twice their body weight in sugary fruit a day. However, unlike humans, fruit bats thrive on a sugar-rich diet. They can lower their blood sugar faster than bats that rely on insects as their main food source.

Keep reading... Show less

Boomers have a drug problem, but not the kind you might think

Baby boomers – that’s anyone born in the U.S. between 1946 and 1964 – are 20% of the population, more than 70 million Americans. Decades ago, many in that generation experimented with drugs that were both recreational and illegal. Although boomers may not be using those same drugs today, many are taking medications, often several of them. And even if those drugs are legal, there are still risks of interactions and side effects.

The taking of multiple medications is called polypharmacy, typically four or more at the same time. That includes prescriptions from doctors, over-the-counter medicines, supplements and herbs. Sometimes, polypharmacy can be dangerous.

Keep reading... Show less

Most Americans are breathing cleaner air — but disparities persist

U.S. air pollution has dropped substantially in recent decades, but not everyone has benefited equally from the decline and some demographics were breathing dirtier air in 2010 than in 1970, according to research set to be published Wednesday in Nature Communications.

Researchers at Columbia University's Mailman School of Public Health studied air pollution changes in the four decades following the enactment of the landmark Clean Air Act, with a focus on racial, ethnic, and socioeconomic disparities in emissions reductions at the county level.

Keep reading... Show less

Bees and wasps join humans in being tricked by illusions of quantity

If you’ve ever been tricked by a visual illusion, you know the feeling of disconnect between what your eyes perceive and what is actually there. Visual illusions occur due to errors in our perception, causing us to misperceive certain characteristics of objects or scenes.

As it turns out, many non-human animals also experience these effects, including illusions of item size, brightness, colour, shape, orientation, motion or quantity. We study these illusions and the differences between animals as it can tell us how visual systems evolved.

Keep reading... Show less