The Tasmanian tiger is still extinct. Reports of its sustained survival are greatly exaggerated.

Officially known in science as thylacines, the large marsupial predators, which looked more like wild dogs than tigers and stretched across Tasmania and mainland Australia, were declared extinct in 1936. On February 23, Neil Waters, President of the Thylacine Awareness Group of Australia, promised conclusive photographic evidence of a surviving Thylacine. The four photos, he claimed, showed a family of thylacines, including a teenage boy, moving through thick brushes. The announcement caused a stir among wildlife lovers.

However, analysis by Thylacine specialists quickly exposed the photos as a case of false identity. The event is the latest in a tradition of flamboyant claims of photographic or video evidence of lost or unknown species that do not show up. Why do these cycles occur so regularly, even convincing experts at times? The answer, say psychologists, could lie in the quirks of the human mind and how we process information that is both familiar and difficult to perceive.

While such footage occasionally turns out to be a joke, many stills and videos depict real animals – even if they’re not what people say they are. In 2005, a WWF camera trap captured images of a “mysterious carnivore” – probably a flying squirrel – in the jungle of Borneo, Indonesia. In 2007, 2011, and 2014, clips from hairless dogs and raccoons in Texas were described as chupacabras.

That same year, a kayaker recorded footage allegedly showing an extinct ivory-billed woodpecker in an Arkansas swamp, generating heated media coverage and widespread scientific interest. Many experts eventually concluded that the bird was more of a woodpecker.

It is not impossible for species believed to be extinct to reappear. Last month there was news of the rediscovery of the Black-Browed Babbler, which has been missing since the 1840s after two Indonesian men captured and photographed a specimen. A day later, an entomologist announced the discovery of a tiny population – just six specimens – of the Australian camouflaged bee, which was last seen in 1923.

This is one of the reasons why the prospect of thylacine exposures has been so compelling to hopeful researchers. Unlike Bigfoot or Nessie, such animals were undoubtedly real, well-photographed during their lifetime, and almost extinct in living memory. Catching a photo of you doesn’t necessarily seem like a stretch.

And in the age of smartphones, cameras are everywhere. In fact, footage captured by camera traps or amateur naturalists can help determine the presence and activity patterns of animals in the environment, said Holly English, a PhD student in wildlife ecology and behavior at University College Dublin.

“There are animals that visit my own garden that I only know through camera traps,” said Ms. English.

Photos can also help reveal animals that live in unexpected places. For example, her research on breeding populations of exotic wallabies in the UK was based in part on images shared on social media.

Susan Wardle, a neuroscientist at the National Institutes of Health in the United States, says cycles of expectant belief that have been undone by deeper analysis can in part be explained by human psychological quirks.

It’s impossible to process every single sensory detail, she says. Therefore, our brain actively reconstructs our visual world based on the complex but ambiguous inputs our eyes receive. Research has shown that unclear sensory data – like a blurry image – causes the brain to rely more heavily on preconceived patterns to make sense of them.

“This means that there is an interesting interaction between perception and knowledge – our beliefs and previous experiences can influence what we see. Or, more precisely, what we think we are seeing, ”said Dr. Wardle.

This tendency can mislead people when examining photographic evidence of long-invisible animals, sometimes referred to as cryptids, especially if they already have an idea of ​​what they are looking for. Many people in search of such enigmatic creatures have an emotional investment in their identification, “and are already convinced that the creatures are already out there,” said Christopher French, who recently graduated from the Goldsmiths University of Anomalistic Psychology Research Unit London established has retired.

This pre-existing belief makes it easier to see quarries in every shadow and rustle of brushes, adds Dr. French, or in photographs that do not offer a clear view of the animal in question. It can also make people really miss details that might contradict their preferred hypothesis.

In a YouTube video posted on February 23, Mr. Waters, formerly a professional gardener, claimed he had recorded footage that proved the thylacine was alive. As he passed a landscape of felled trees, he described how he set up camera traps in the Tasmanian bush and captured four “non-ambiguous” stills of a Thylacine family.

Thylacine populations began to decline shortly after European settlers arrived on Tasmania, an island south of mainland Australia, in 1803. The last known person, “Benjamin”, died in captivity in 1936, leaving only haunting portions of the footage.

In the decades that followed, sightings were reported that drew multiple expeditions into the Tasmanian wilderness in search of survivors, said Darren Naish, a paleozoologist at the University of Southampton in England. None was successful. However, reported sightings continued and even increased through the 1980s and are still reported today.

“That suggested sightings were a social phenomenon, not a zoological one,” said Dr. Naish.

Mr. Waters sent his photos to the Tasmanian Museum and Art Gallery for analysis by Nick Mooney, a thylacine expert. He and his colleagues debunked Mr. Waters’ allegations.

“TMAG regularly receives review requests from members of the public who hope the thylacine is still with us,” said a statement from the museum. “Based on the physical characteristics in the photos of Mr. Waters, it is very unlikely that the animals are thylacine.”

Instead, they said they were most likely Tasmanian pademelons, a stout little marsupial resembling a wallaby.

Many thylacine sightings are similar misidentifications, said Adam Pask, a thylacine researcher at the University of Melbourne. “There are some wild dogs in Tasmania,” said Dr. Pask. “So it’s very easy to spot a thylacine-looking animal in the bush, if you look closely enough and want to see one enough.”

These types of mistakes are common, said Dr. Naish, in part because even seasoned people and researchers outdoors are not always able to identify animals from unknown angles or in unknown states. Size and distance can be difficult to judge in photos, causing domestic cats to resemble large cats. Subtract fur, as is the occasional rotting raccoon carcass or mangy fox, and even familiar mammals can look profoundly scary – or like an extinct marsupial predator.

“We all make mistakes: even the most experienced naturalists make false identifications, sometimes weird,” said Dr. Naish. However, those who devote themselves to the hunt for cryptic animals are often prepared to accept ambiguous footage while rejecting critical opinions from qualified experts.

“The most common cognitive bias we all suffer from is confirmation bias,” said Dr. French. If you invest in finding the cryptid you are looking for, the more likely you will find the evidence compelling.

On March 1, Mr. Waters – who did not return multiple requests for comment – posted the photos as part of a 19-minute video and urged viewers to “choose”. In a subsequent interview with News.com.au, he said that the response to his photos by expert analysts “put more fire in my stomach to prove them wrong”.

“It won’t be long now,” said Waters. “Because we are very close to irrefutable evidence, the animal is still here.”