Back from the dead?
No I am not talking about zombies or white walkers (for my Game of Thrones fans). I am talking about a species that were considered extinct... once. Let's face it, if you're a science fiction fan, you've probably come across a movie or book where some intrepid explorer comes across an organism that "...hasn't been seen for millions of years!", maybe something akin to a mosasaur or some other large animal. Excitingly, this sort of serendipitous discovery isn't relegated to mere science-fiction and fantasy!
According to www.encyclopedia.com "Lazarus taxon"- A taxon that disappears from the fossil record close to an extinction horizon, but reappears again much later in the [geologic] sequence. To translate science-speak into "normal English" , a Lazarus taxon is a species that has been previously declared extinct but found to be alive years later, and there are more of these species than you might imagine. I'd wager that you've only heard of one of the ones that will be discussed here and that's cool. Heck even I only knew of the one before I started my research, and that's because the species FASCINATES me! But before we go any further, if your New Testament stories are a little fuzzy, Lazarus is the man that Jesus is said to have raised from the dead... (but he was not a zombie).
Let's start with Chelonoidis phantasticus, commonly known as the Fernandina Island Galápagos tortoise. This species had been known from a single, male found (and sadly, killed) by the 1906 California Academy of Sciences expedition. It was thought at the time, that the volcanic activity on the island was what drove the tortoise to extinction and it would be another 58 years before a bite mark on a cactus would even SUGGEST the species was actually alive! 2009 had an unconfirmed sighting and 2013 saw another one of these suspicious bite marks but, sadly, no actual proof. Incredibly, a total of 113 years would have to pass from the 1906 encounter before an expedition funded by Animal Planet, would confirm this species was still extant when a single female was found alive. Work is ongoing, looking for a male to help ensure they truly don't go extinct, but they are alive and critically endangered! Want to know a little more about the Fernandina Island Galápagos tortoise? Visit Tropical Herping's site on them.
Next on our list of risen-from-the-dead species is Cliona patera, commonly called Neptune's Cup sponge and is our next Lazarus taxa (plural of 'taxon'). Named after the Roman god of the sea, this sea sponge grows up-to-3-feet tall, in a wine-glass shape and is one of the larger species of sponge. It had been first harvested in the waters of Singapore, Java and Indonesia as early as 1822. By 1908 no more were seen in their natural waters due to overharvesting although dead ones had been seen in the 1990s on Australia's coast. Now fast-forward 20+ years from then and imagine divers' shock when, in 2011, they were found growing! An older Scientific American blog posts discusses more if you're interested. Sadly, because of its recent discovery, not much is known about the species but like many other Lazarus taxa, research is being conducted to learn more.
We move to the southern hemisphere for our next used-to-be-extinct animal, Porphyrio hochstetteri, also known as the South Island Takahē; a flightless bird native to New Zealand. This bird was first discovered in 1847 and the last one was captured in 1898. From that last capture, the bird was assumed extinct. It would be 50 years until the bird was rediscovered thanks to the work of tramper or "bush walker" Dr. Geoffrey Orbell, who had suspected that the bird might still be alive. Eventually found in the Murchison Mountains of the south island of New Zealand, the birds are now considered endangered and "Nationally Vulnerable" according to the New Zealand Threat Classification System. Thankfully, these birds are now managed by the New Zealand Department of Conservation, whose Takahē Recovery Programme maintains populations on several offshore islands as well as Takahē Valley and has even reintroduced them into the Kahurangi National Park! Slowly but surely, they're making a comeback!
Don't tell this little guy he's extinct. The Starry Night Toad (Atelopus arsyecue) is native to the Sierra Nevada de Santa Marta, Colombia. It has been facing steady and constant pressure from habitat loss (at the hands of humans) as well as other, more natural pressure from mother nature herself. Chytridiomycosis is an infectious disease in amphibians, caused by the chytrid fungi and has been known to wipe out entire species of amphibians. Since this Chytridiomycosis is a naturally occurring pressure, little can (and should) be done to help; it's an example of Darwin's "survival of the fittest" in action. Found 30 years after it was considered to be extinct and thanks to the efforts of local tribes, this species was found alive in 2019; these toads have made the "come back" to the living after 30 years of being extinct!! If the toads who are resistant to Chytridiomycosis can breed sufficiently fast enough, these little guys will survive and be a shining example of Darwinism. You can imagine the difficulty in spotting a small animal such as the Starry Night Toad because of its small size and quickness especially when a human were to trundle near it. This could lead you to understand how an organism might elude human eyes for over three decades!
Our last Lazarus taxon is my favorite because it's long been described as a "living fossil", thought to have gone extinct around during the time of the dinosaurs and dying out at roughly the same time. Yes, that's correct, our last Lazarus taxon was not known to be alive for over 65 million years!
Latimeria chalumnae or Latimeria menadoensis, depending on which of the two species you're referring to, are collectively known as the Coelacanth (pronounced “see-lah-kanth”). These incredible fish are related to lungfishes and tetrapods. They were believed to have been extinct since the end of the Cretaceous period! While seen in the fossil records, it was only 1938 when the first live specimen was caught in the Indian Ocean. They are called a "living fossil" because of their (current) close resemblance to those found in the fossil record. This fish enjoyed its anonymity for over 65 million years all while staying almost exactly the same, physically-speaking! The amazing thing about this fish is it's relation to other animals. They are more closely related to lungfish and tetrapods (which includes amphibians, reptiles, birds and mammals) than to ray-finned fish; this is because they are known as "lobe-finned fish". These fins are more like hands or feet than they are true fins. Currently they are only found along the coastline of Indonesia and the coast of western South Africa in the Indian Ocean; both coelacanth species remain critically endangered. And although not much is known about these species in terms of aggressiveness or socialness, research is being conducted on their genome and how it's changed. Gizmodo has a great article if you want a casual peak inside their genetics. And if you're really feeling like you want to know more, Smithsonian gets in depth (no ocean-pun intended) with their write up on the Coelacanth or visit Earth Touch News Network for an article and video of it swimming in situ!
Lazarus might have risen from the dead in biblical stories but these are only a few examples of life proving history wrong. Who knows what sort of species might show up next after being "extinct"!?