Scimitar-toothed Cat

There is no physical evidence for the scimitar-toothed cat having haunted the Clwydians – nor indeed of it having inhabited Wales. But, as the saying goes, an absence of evidence is not evidence of absence. Their fossils are incredibly rare – though some teeth and bones were found at Dove Holes in the Peak District, less than a 100 miles away. But DNA analysis tells us that some species – like the Iberian lynx – can keep going at very low population levels, making them and their remains incredibly difficult to find. And research by Ross Barnett shows that the scimitar-tooth Homotherium which ranged across Europe is virtually identical to North American specimens. 

All of this grants us licence – to imagine that our very own Diego once stole through these hills bearing long slim, dagger-like teeth with distinctive serrated edges; terrifying carving weapons capable of inflicting wounds that caused death by blood loss. 

So then; we will have this fell beast in our Ghost Menagerie – partly because it’s fabulous, but also because of what it tells us about scientific truth and nomenclature; the Naming Of Things.

When first discovered in Italy in the early nineteenth century, these extravagant teeth were thought to belong to a bear – the best fit given the knowledge of the time – and so the new species was given the name Ursus cultridens. Since then, as a consequence of a small number of further discoveries, this classification has changed several times with the bear becoming a cat – sort of. Ursus cultridens became Machairodus cultridens (of the Pliocene Epoch) – and Machairodus latidens (of the more recent Pleistocene) also came into being as a more recent type was identified. Then Machairodus got dropped and the same animal became Homotherium. 

So in 2020 (for now) we have Homotherium crenatidens and Homotherium latidens. Both, it has been deemed, sat on a branch of the Tree of Life somewhere between the boughs occupied by cats and hyaenas respectively. Whether there is sufficient difference between cultridens and latidens to support their status as separate species seems to be a moot point – a consequence of the spectacular complexity of evolution; things just aren’t always immediately black and white, particularly when there is such a small pool of evidence to sift through.

The point at which Homotherium latidens went extinct has also been the subject of protracted debate. Crenatidens as a species is perceived as straddling the Pliocene and Pleistocene – disappearing around two and a quarter million years ago. Latidens is viewed as a creature of the Pleistocene, which ended with the last Ice Age 11,700 years ago. But quite when within this span its final demise occurred… well; academic horns have been well and truly locked over this vexatious question.

Calm eventually descended with the agreement that the last Homotherium expired around 300,000 years ago. But then, in the year 2000, a trawlerman cast his vast, seabed-scouring net into the North Sea and hauled up an unmistakably shaped mandible – of Homotherium latidens. Despite having lain on the bottom for millennia its preservation was good enough for one of its teeth to be sampled for radiocarbon dating. This, somewhat unexpectedly, returned a date of 32,000 Years BP. So; with one whizz of the dentist’s drill and a spin in the Machine That Goes Ping, the Homotherium story was altered by over a quarter of a million years. Where were these complicated creatures hiding all that time?

This is the sort of story that elicits the rolling of eyes amongst pub philosophers (and journalists) who rail against the ‘indecisive’ nature of scientists. “They can’t make their minds up!” they roar from the bar; “they don’t know anything!”

But, in fact, it represents the reality and humility of contemporary science. With new discoveries the story will inevitably change – and we should acknowledge and applaud this rather than howling with derision. The phrase ‘the truth for now’ is a good one. 

Also good when seeking to establish a widely accepted truth, is the system of peer review on which global science is founded; a question (or hypothesis) is established, relevant research undertaken and – most importantly – the resulting findings are then assaulted by a group of people with extensive relevant knowledge and experience. For this to work, ego must be pushed to one side and as questions are raised and answered, the greatest cynics must be scientists themselves.

In 2013, a study based on this same rigorous process found that in 4,000 scientific papers expressing an opinion on the cause of recent climatic warming, 97% agreed not only that global warming is happening but that we are causing it – a consensus of overwhelming scale. 

Western science is a good system. It’s not infallible – and it doesn’t constitute the sole truth. Nor can it provide all the answers. But, practiced with integrity and humility, it’s probably the most effective way we’ve devised yet whereby humanity can come together and communicate as one in the search for solutions to the very great challenges that we now face.