91av

AYUMU the chimpanzee sits behind a glass wall taking a memory test. He sees a sequence of numbers randomly set out on a touchscreen, memorises them and, when they disappear, taps out a pattern to indicate where they were. For a correct answer, he is given a small reward of food.

The ape featured in Super Smart Animals, and the research he was involved in at Kyoto University in Japan revealed that young chimpanzees have a better working memory for numbers than human adults. The experiment with Ayumu is just one example of research that is confirming how sophisticated animal minds can be.

“You might assume that giving lab rats larger cages is a good thing, but that’s not necessarily true”

The trouble is, many studies like these involve housing animals in laboratory conditions or incentivising them to do a test by restricting their food or water. In recent months, 91av has reported on findings that chimps bond after watching films together macaque monkeys can use logical reasoning to solve puzzles and that implanting memories in the brains of zebra finches can alter their songs. All these studies involved manipulating animals in unnatural ways.

There has long been a debate about the merits of animal experiments, especially in medical research. But when animal behaviour or cognition experiments are unlikely to lead to medical advances, the purpose of such studies can seem less immediately clear.

In the US, the total number of animal studies under way is difficult to come by because there is no requirement to record experiments involving mice, rats and fish. However, the US Department of Agriculture does report the use of cats, dogs, farm animals, non-human primates and a few other species. In 2017, its records show that that involved pain and being given pain-relieving drugs. Some 30,000 of these were non-human primates.

In Great Britain, we know that, in 2018, there were , as well as how this breaks down by animal and type of experiment (see statistics, far right). Still, the figures don’t tell us what proportion of these experiments are done to find out about animal cognition.

The purpose of animal cognition research can seem less obvious than medical experiments. One driver is to learn about ourselves. “I want to understand how brains evolve,” says at Newcastle University in the UK. “From my perspective, just studying humans doesn’t get you anywhere. To understand evolutionary patterns and processes, you need a wide range of species.”

Cognitive research is also conducted in the pursuit of basic knowledge. In the early 17th century, René Descartes thought that animals didn’t feel pain or experience emotions – that they were a kind of unconscious organic mechanism. But experiments have shown that some creatures seem to have cognitive abilities that begin to approach our own (see “Minds of the beasts”).

Learning more about how animals tick can also boost conservation efforts by assisting captive breeding projects and subsequent releases.

Opinions as to whether these are good enough justifications for animal experiments are split. “It’s a dilemma, and I struggle with it a little bit myself,” says Smulders.

One thing is for sure: if the overall goal is conservation, lab experiments on animals can’t tell us much in isolation.

Playing chess

Think, for example, of the 1950s studies in which chimps played chess, says at the University of Veterinary Medicine Vienna in Austria. They told us that chimps had the curiosity to try out the game. That knowledge couldn’t be used for conservation, though, because the setting was so far removed from the animals’ natural environment.

Huber says we should instead be doing lab experiments and field observations in conjunction. “We need to know what is the real problem the animal is solving in the wild,” he says.

To conserve birds, it may be reasonable to do systematic lab experiments to get rigorous evidence on how they remember where they have stored food, for instance. But we would also need to study them in the wild to see how that translates into real behaviour.

Deciding whether animal experiments of any kind are worthwhile also involves balancing potential harm to the animal with the wider benefits. For example, testing drugs on animals may hurt them, but the medical benefits to people might be seen to outweigh that harm.

Studies of animal cognition are a far greyer area, however. Public opinion is already divided on the wider issue. A 2018 Pew Research Center poll found that .

We do have ways of trying to ensure that animal research leads to benefits. In the US, the National Academies of Sciences, Engineering, and Medicine states that show “relevance to human or animal health, advancement of knowledge, or the good of society”. That may sound generic, but there are also specific rules that lay out the physical environments required for laboratory animals. These include everything from heat and humidity to how much vibration an animal can experience.

In fact, those guidelines were informed by the very research they are designed to oversee. Experiments on animals that tell us about their minds and how they experience the world can also tell us how best to keep those animals content. It is a positive feedback loop.

This has led to real improvements in rodent research. Rats and mice used to be housed in stark cages on their own. “That’s illegal now,” says Smulders. “It’s required and routine to give them bedding materials, places to hide, chewing tubes. These things have changed precisely because there’s more of an understanding now that these animals do have feelings of their own.”

But shouldn’t it be possible to treat animals well without having to experiment on them to find out what they need? It isn’t necessarily that simple. You might assume, for instance, that it would be a good thing to give rats larger cages, but that may not be true. have shown that rats’ stress levels are lowered by having places to hide and being housed with other rats. It isn’t more space that’s important, but the right kind of space.

Ultimately, finding out the best way to improve the lives of animals comes down to evidence. Here’s the paradox: to treat animals – whether on farms, in labs or even in the wild – with the respect many feel they deserve, we must understand the ways we affect their lived experience, and to do that in a detailed way we may need to study them closely in the lab.

“We keep animals in zoos and circuses, use them for our meat. We do lots of harm to animals. Is this justified?” says Smulders. The only way to answer that question, he says, is to do experiments. “It’s not enough to sit in an armchair and think about it. You have to investigate it and prove it.”