Dogs seek the north, bumblebees play ball: 7 real-life studies of animals

Science sometimes poses questions that, without a DOI, could easily be mistaken for a joke. Why does a wombat leave behind cubes? Where does a dog look when it relieves itself? Is it possible to teach a rat to play hide-and-seek, or a parrot to ring another parrot itself?

We’ve compiled seven published studies where the subject matter itself seems rather unusual. We haven’t added anything to the findings: each item has been verified against the original article, its DOI or an official university repository.

Details

How we selected them. The selection includes studies with a verifiable original source and a sufficiently clear result. This is not a ranking: the order does not imply that one study is ‘funnier’ or more important than another. Where authors constructed a model or discussed only a possible interpretation, this is noted separately.

In short:

1. Wombats do indeed form faeces with flat faces and corners.
2. For penguins, scientists calculated the pressure required to expel faeces from the nest.
3. Dogs in a stable geomagnetic field were more likely to orient themselves along a north–south axis whilst defecating.
4. Rats learnt to play hide-and-seek with humans without any food reward.
5. Bumblebees repeatedly rolled wooden balls without any obvious practical benefit.
6. Pigeons learnt to distinguish between paintings by Monet and Picasso and transferred this skill to new images.
7. In an experiment, parrots initiated video calls to other parrots of their own accord.

1. Wombats and cubic droppings

In 2021, the journal *Soft Matter* published a paper on how the gut of the naked-nosed wombat forms its famous cubic faeces. The researchers combined post-mortem examinations, histology, mechanical tissue tests and mathematical modelling.

According to the study, the cubic shape forms in the final 17 per cent of the gut. The authors identified sections of the wall that are approximately twice as thick and four times as stiff as neighbouring sections, and proposed a mechanical model in which the alternation of stiffer and softer zones helps to form the faces and corners. This is precisely the proposed mechanism, rather than a claim that all the details of the process have been definitively established.

2. Penguins and pressure calculations

In a short article in *Polar Biology*, Viktor Benno Meyer-Rochow and József Gal solved a physics problem: what pressure does a penguin need to expel droppings as far as possible from the edge of the nest?

The authors used the dimensions of the opening, the bird’s height, the distance the droppings travelled, as well as estimates of the material’s density and viscosity. For liquid contents, the model yielded a figure of around 10 kPa; for more viscous material, around 60 kPa. Importantly, this is a calculation based on measured parameters, not a direct measurement of the pressure inside a living penguin.

3. Dogs and the north–south axis

In a 2013 study, researchers observed 70 dogs of 37 breeds over a two-year period. They recorded 1,893 instances of defecation and 5,582 instances of urination, and then compared the orientation of the animals’ bodies with the state of the Earth’s magnetic field.

When the geomagnetic field was stable, the dogs were more likely to align themselves along the north–south axis whilst relieving themselves. When the field was unstable, this pattern disappeared. The study demonstrates a behavioural link with geomagnetic conditions, but does not explain why dogs adopt this orientation or exactly how they sense the field.

4. Rats that played hide-and-seek with humans

In 2019, a paper was published in *Science* describing a game of hide-and-seek between rats and experimenters. The animals were trained to alternately search for a human and hide from them. No food was given as a reward for success: once the participants found one another, a playful interaction followed.

The rats quickly mastered both roles. Whilst searching, they used visual cues and memories of previous hiding places, and when attempting to hide, they preferred opaque hiding places to transparent ones and emitted ultrasonic signals less frequently. At the same time, the researchers recorded activity in the prefrontal cortex.

5. Bumblebees rolling balls without a reward

A study in *Animal Behaviour* investigated whether bumblebees rolling wooden balls could be considered a form of play. In one experiment, 45 bumblebees could either head straight for the food or veer off towards an area with moving balls. They received no reward for rolling the balls.

The researchers recorded 910 instances of ball-rolling; some bumblebees repeated the action up to 117 times during the experiment. The authors tested alternative explanations — foraging, clearing a path and courtship behaviour — and concluded that the behaviour met the accepted criteria for play. Young bumblebees rolled the balls more frequently, whilst males rolled them for longer than females.

6. Pigeons that could distinguish between Monet and Picasso

In 1995, the *Journal of the Experimental Analysis of Behaviour* published an experiment in which pigeons were trained to distinguish between colour slides of paintings by Claude Monet and Pablo Picasso.

After training, the birds were able to recognise new paintings by these artists that they had never seen before. They also extended this ability to works by other artists: from Monet to Cézanne and Renoir, and from Picasso to Braque and Matisse. This does not mean that the pigeons ‘understood art’: the study demonstrates an ability to classify complex visual stimuli according to consistent characteristics.

7. Parrots that made video calls to other parrots

At the CHI 2023 conference, researchers presented a three-month experiment involving 18 pet parrots. The system allowed the birds to initiate a video call to another parrot, and the decision to make the call had to come from the bird itself.

During the study, there were 147 bird-initiated calls, and all participants used the system. According to the authors, most birds demonstrated high motivation and intent, whilst owners reported positive changes. However, the sample size was small, and some of the assessments of benefit were based on the owners’ observations; therefore, the study does not prove that video calls are universally beneficial to all parrots.

Why this matters

A humorous research question does not make the study any less serious. Behind the unusual phrasing in these studies lie quite ordinary scientific objectives: the mechanics of soft tissues, magnetoreception, the neurobiology of play, learning, image categorisation, and technologies for enriching animal environments.

At the same time, such research clearly illustrates the limits of interpretation. A pigeon that can distinguish between Monet and Picasso does not become an art critic. Calculating pressure in a penguin is not the same as a direct physiological measurement. And the preference of parrots for video communication in a small sample cannot automatically be generalised to all pet birds.

So the most amusing thing here is not a made-up retelling, but the fact that scientists actually posed these questions, devised a way to test them and published the results.

Source

• Yang P. J. et al. Intestines of non-uniform stiffness mould the corners of wombat faeces. Soft Matter, 2021. DOI 10.1039/D0SM01230K.
• Meyer-Rochow V. B., Gal J. Pressures produced when penguins poo—calculations on avian defecation. Polar Biology, 2003. DOI 10.1007/s00300-003-0563-3.
• Hart V. et al. Dogs are sensitive to small variations in the Earth’s magnetic field. Frontiers in Zoology, 2013. DOI 10.1186/1742-9994-10-80.
• Reinhold A. S. et al. Behavioural and neural correlates of hide-and-seek in rats. Science, 2019. DOI 10.1126/science.aax4705.
• Samadi Galpayage Dona H. et al. Do bumblebees play? Animal Behaviour, 2022. DOI 10.1016/j.anbehav.2022.08.013.
• Watanabe S., Sakamoto J., Wakita M. Pigeons’ discrimination of paintings by Monet and Picasso. Journal of the Experimental Analysis of Behaviour, 1995. DOI 10.1901/jeab.1995.63-165.
• Kleinberger R. et al. Birds of a Feather Video-Flock Together. CHI 2023. DOI 10.1145/3544548.3581166.