Have you ever heard of Lazarus taxa? If you're familiar with who Lazarus was then you might be able to guess why his name is used to describe these animals. According to Christian teachings, Lazarus was a man, whom Jesus was able to perform a miracle for and bring back to life. Similarly, Lazarus species are those which were accepted by the scientific community to be extinct, until they weren't!
Ok, so I suppose to start with we should kind of ask ourselves, what actually makes an animal extinct? How can you categorically and without doubt say that there are no more of this animal to be found anywhere on our planet. The short answer is, you can't. Declaring an animal extinct is not simply a check the box exercise, and the scientists involved in making those kind of decision must take great care to show they have done their due diligence.
In most cases, to declare an animal extinct in an area, there have to be extensive population studies conducted to try and establish if any individuals remain. After that, an extended period of time without any verified sighting of an animal must pass before an animal should official get stamped as extinct in an area. The International Union for the Conservation of Nature (IUCN) are possibly the most well-known and best source of information for people to find the status of species. In their criteria for declaring an extinction, they have for years worked off the requirement that no verified sighting has been recorded for fifty years OR that for whatever reason, no reasonable doubt exists that a species is still present within it's range.
So then your species is extinct. Gone. "Just like that", to quote one of my favourite comedians. Tommy Cooper, for any of you that need more procrastination material. But then! On occasion, a miracle happens, and like Lazarus, the species raises itself from the dead by suddenly appearing once more. One of the most famous examples of that is probably the coelacanth. This prehistoric fish had been recorded by scientists through the fossil record and conclusions were reached that it had gone extinct sixty-five million years ago. These conclusions were proved wrong in the 1930s when fishermen in the Indian Ocean found one at the end of their lines.
And, as if a single re-discovery wasn't enough, a second species of living coelacanth was found by an ichthyologist on honeymoon to Sulawesi. In 1997, Dr. Mark Erdmann saw a coelacanth, caught by locals, being sold at a local market and walked away, thinking that he was wrong in his identification. The following year, Dr. Erdmann returned to Sulawesi and offered a reward for a the fish locals called "raja laut" and was fortunate enough to have one brought to him alive which he was able to photograph in it's last moments before it was removed from the water. The story gets more dramatic from there with double-crosses and betrayals, but that isn't relevant to what I'm talking about. If you're interested in the full story you can find it here; A Living Reef Fossil: New Population Of Coelacanth Discovered (reefs.com).
At this stage you may be asking how animals can just be re-discovered when one of the criteria for an extinction status is that thorough studies have to be conducted to find them in the first place. Well, quite simply. No system is perfect. We can only do so much and the researchers out there in the field are not able to dive into every nook and cranny of existence. I mean, to go to a well-used example, it wasn't until 2008 that a significant population of lowland gorillas were found in the Republic of the Congo. It wasn't for lack of trying on behalf of researchers that they weren't found, the world is just a big place.
So occasionally animals can come back to life, and I have to say, is that a good thing? I mean, don't get me wrong, I am a conservationist. My goal is to work towards preserving and protecting species that are in trouble, but where is the line drawn. One of my lecturers posed the trolley problem to us one day in class, when I was doing my undergrad, but put it in the context of available resources for conservation.
If you're unfamiliar with the trolley problem, it's a moral paradox. Imagine yourself driving along in a tram and the brakes fail. You see ahead of you a split in the track. On your side are a group of school children playing, on the track you can change to is an elderly man going for a walk who has stopped on the track. Do you change tracks? How do you argue this?
For us, my lecturer asked us if you have limited resources but two species that are in trouble of going extinct, which do you choose? They are plenty of factors, but one would be the size of the population. Is the size of the population large enough to viably continue breeding and survive? This is where I begin to question the benefit of a Lazarus species. If a species has a population so small that it has been considered extinct for decades and then it pops back up, should valuable resources be spent to preserve these animals when another, equally important, species has a better chance?
I worry that the fascination we have with the mystery of Lazarus species might lead to inefficient choices being made. If you can't understand where I'm coming from then I would urge you to consider the thylacine as an example. Thylacine, or tasmanian tigers, went extinct in 1936 when the last known individual, called Benjamin, died in captivity. The thylacine was a beautiful and majestic animal and has captivated the imaginations and love of people all over the world, including myself. Since Benjamin's death there have been hundreds of recorded sightings of thylacine living in the wilds of Tasmania and South-Western Australia. But there, has been no actual verifiable proof that this animal is still alive.
While I would be overjoyed to find out that thylacine are still extant in Tasmania, a small part of me wonders if it would justify the amount of resources that have been put into the search to verify the continued existence of these animals. On one hand, should we be expending the time and manpower into a search for an animal who, should it be found, may end up dying out anyway? On the other hand though, these kinds of species draw the attention and love of people all over the world to the plight of species like them and help to open up people's hearts and minds to the idea of conservation and protecting the natural world. It's a complicated question. There isn't necessarily a right answer and at the end of the day, things usually don't come down to such a simple decision, but I think it's worth thinking about and keeping in mind.
I'll end my ramblings here for now I think but if you found this interesting or have any opinions about Lazarus taxa or my trolley problem then please let me know by sending me a message! Thanks for reading.
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