Why sheep were taught to recognise BARACK OBAMA
...not to mention the rats that learned to drive cars — as part of research to improve human health
YOU might have taught your dog to sit or perhaps tutored your cat to respond to their name. But this pales into insignificance when compared with some of the skills other animals are learning in order to improve human health.
Recently, Good Health revealed how scientists have trained bees to play football as part of work to help us understand how human memories work.
The bees had to move a little ball to a goal and if they did that they got a reward (a drop of nectar); in this way the bees learned to commit the skill to memory.
Scientists say bees can help further our understanding of human recall as they memorise a lot on a daily basis, such as landmarks to help them navigate to and from their hives.
But they aren’t the only clever creatures being trained to perform tasks that will ultimately help our health, as you can see from these amazing images.
CANCER-SNIFFING ANTS
In March, a team of researchers in France published a trial, in the journal iScience, revealing they had trained ants to detect cancerous cells in a petri dish — with as little as 30 minutes’ training.
‘Cells are like tiny factories — they need fuel and they produce waste — and the ants, which have an impressive sense of smell, can detect the specific type of waste given off by cancer cells,’ explains Professor Baptiste Piqueret, a researcher of animal behaviour and lead author of the trial.
The ants were trained by putting them in a space along with a container of sugar solution next to a sample containing ovarian cancer cells from human patients.
While drinking the sugar solution the ants could also smell the cancer cells and they started to associate this scent with reward — and seek it out.
Professor Piqueret, now based at the Max Planck Institute for Chemical Ecology in Germany, says the trials are in the early stages.
‘You won’t see ants in hospitals yet, as the future of this method is to use not cells but urine or sweat — we expect one day you’ll give a sample to your doctor and that will be presented to trained ants to see if they react to it,’ he says.
This might in future be a less invasive option to a biopsy, the surgical removal of tissue to test for cancer.
Other animals are already known to sniff out health conditions.
Dogs have been trained to detect Covid-19 infection and can be used to alert their owners of impending falls in their blood sugar or epileptic seizures.
‘But the ants learn far faster than dogs do, in minutes rather than months,’ says Professor Piqueret.
CAR-DRIVING RATS
BEHAvIOURAl neuroscientist Professor Kelly lambert, from
Richmond University, virginia, in the U.S., has taught rats how to drive miniature cars.
In the experiment, the animals drove by pushing on bars that take them left and right — the object being to learn how to navigate the car towards a snack.
‘While we have to be careful not to give human attributes to animal behaviour, they do look like little humans when they first get in the cars, sticking their heads out the windows as if they’re checking the traffic,’ says Professor lambert.
‘They act excited when we bring them into the driving room and, even though we recently stopped reinforcing them with treats, they still drive the cars, so it seems as if they enjoy it.’
But why did Professor lambert want to do this? ‘Rats share similar brain areas, cells and neurochemistry to humans and because driving involves cognitive and emotional variables, it provides an opportunity to assess these,’ she explains.
The findings may also ultimately help us examine how changes in movement or spatial skills occur with age, or in degenerative conditions such as Parkinson’s.
MEMORABLE SHEEP
A 2017 study in the journal Royal Society: Open Science showed that sheep can be trained to recognise faces — which may have surprising knock-on benefits for human health.
To train them, the sheep were given treats when they picked the face of a celebrity from a choice of two pictures. Eight sheep were trained to recognise famous faces such as Barack Obama and actress Emma Watson.
It’s hoped that examining things like how the sheep’s ability to recognise the faces changes over time may help us understand the cognitive effects of conditions such as Huntington’s and Alzheimer’s.
The researchers turned to sheep because they live a relatively long time — ten to 12 years on average — their brains are as complex as ours and, ‘importantly, because there are at least 16 genetic diseases caused by the same gene in sheep as in humans, including Huntington’s and Batten disease, a serious degenerative disease that affects children,’ explains the study’s author Jenny Morton, a professor of neurobiology at the University of Cambridge.
‘Cognitive decline in these
conditions is very hard to measure in humans — but this study gives us a way to monitor how abilities change, particularly in sheep that carry a gene mutation that puts them at risk of these diseases.’
PATHOLOGIST PIGEONS
In 2015, a team at the University of Iowa in the U.S. taught a group of pigeons to differentiate cancerous breast tissue from benign tissue on a mammogram — and in 2020 the same team published a paper in the journal Learned Behaviour explaining how they’d now taught five pigeons to spot abnormal heart scans.
Why pigeons? Because studies have shown that they are good at classifying objects into groups and the team wondered if they could also read medical scans.
The test they looked at is known as a Myocardial Perfusion SPECT test and it measures how well the blood is flowing through the heart muscle.
A traceable agent is injected into a vein and tracked through the body. Healthy tissue absorbs the tracer, damaged tissue does not — and this shows up as different colours on a scan.
The pigeons were shown scans and taught to peck at two buttons — normal or abnormal.
If they got their choice right, they were given food.
In time, they learned what was different about the pictures that showed normal or abnormal and pecked at the right one 80 to 85 per cent of the time, which is the same rate at which trained humans can read scans correctly. But then they were tested looking at black and white pictures — and, even though the information was the same, they couldn’t spot which image was normal or abnormal as effectively.
This finding is surprisingly useful. ‘The medical imaging community is constantly evaluating whether to use artificial colour to convey this type of information and which colours to use — and this study showed that adding colour helps a lot,’ explains Victor navarro, who worked on the Iowa trial but is now a research associate at Cardiff University.
‘The idea behind all our projects was never to replace human experts doing the diagnostic work but to use the pigeons as a way of evaluating novel imaging techniques.’
MOTIONLESS DOGS
TEACHING a dog to sit is one thing, but a team at Emory University in the U.S. have gone further — they’ve trained dogs to lie in MRI scanners, a process that