Author: Jun Ammonite of the Sea of Tranquility
In northeastern Australia, a sharp angle points straight to the island of New Guinea, where Cape York, Queensland, is inaccessible and poorly soiled, it is the last wilderness on earth and home to countless wild animals.
But just recently, this place has attracted a lot of attention, because the Thylacinus cynocephalis (Thylacinus cynocephalis) that have been extinct for 81 years may appear here.
Everyone knows kangaroos, wombats, but what is a thylacine? It was once the top predator on the Australian continent and the world's largest marsupial carnivore.
On 10 July 1936, the Government of Tasmania, Australia, introduced an administrative protection order for thylacines, which was probably the most embarrassing protection order in history, because after 1933, no thylacines were found in the wild, and on the 59th day after the order, the last member of the species died in captivity in the zoo.
The last thylacine, a female known to later generations as "Benjamin," was captured from the wild in 1933 and sent to the Bomaris Zoo in Hobart. The zoo had very serious staff management problems between 1935 and 1936, which led to a large number of animals not being properly and carefully cared for.
Just in early September 1936, Hobart experienced rare extreme weather, with temperatures soaring to 38 degrees during the day and minus 1 degree at night. Due to the negligence of the thylacine keeper, the gates of the barn that should have been open were closed, and the last thylacine could not return to its house, but remained exposed to the open metal cage. On the night of September 7, she was unaccompanied, tortured, and finally died silently in the long night. Her death marked the extinction of the species of thylacine and the end of a family that had been on Earth for 25 million years.
The last thylacine "Benjamin". Image source wikipedia.org
In the years since the thylacine's extinction, people have seen its apparitions more than once, but each quest has ended in disappointment.
Maybe this time will be different? Two sightings were from an old Employee of the Queensland National Park Service and a guide who often camped in northern Queensland. They all saw an "animal that looks a bit like a dog." Professor Bill Laurence of James Cook University in Australia said that according to the descriptions of two witnesses, the animals' eye color, size, shape and behavior were extremely close to those of thylacines.
So, in April, cook university scientists decided to start a thylacine hunt at York Point. Dr. Sandra Abell, another researcher at Cook University, is going to set up at least 50 camera traps there, where sensors will automatically sense and take pictures as animals approach.
Cook University announced march 24 to conduct a thylacine search. Image source: jcu.edu.au
This time, will humans see the thylacine again?
First acquaintance, from "dog-headed possum" to "dog-headed thylacine"
Europeans first saw the thylacine in 1642, when Dutch navigator Abel Tasman described the strange animal footprints after landing on Tasmania. The first definitive record was recorded in his diary on 13 May 1792 by Jacques Labillardière, a naturalist on an expedition led by D'Entrecasteaux. However, it was not until 1805 that The Acting Governor of Tasmania, William Paterson, published a detailed description in the Sydney Gazette.
The first detailed scientific description of the thylacine was completed in 1808 by George Harris, but limited by the scientific taxonomic system of the time, he classified it as the indigenous marsupial genus of North America, the genus Didelphis, and named it "Didelphis cynocephala" based on its unique dog-like head morphology.
With the study of australian marsupials, it has been learned that Australian marsupials are completely different from north and South American marsupials, which has led to a re-scientific classification of Australian marsupials. In 1810, the anatomist Geoffroy Saint-Hilaire classified the thylacine into the genus Dasyurus, which he established in 1796, and revised the species name of the thylacine to cyclocephalus. It was not until 1824 that Temminck established a separate genus for the thylacine, Thylacinus, the model species of Thylacinus cynocephalus. The scientific name of the genus Thylakos consists of two Greek words, Thylakos, the former meaning "bag", the latter meaning "dog", and the combined meaning is that the thylacine looks like a dog with a nursery bag. The meaning of the species name is "dog-like head".
Thylacines in captivity. Image credit: Zoological Society of London
The thylacine family can be traced back to the Late Oligocene, the earliest members of the modern thylacine genus were in the Early Miocene, after which members of the thylacine family gradually spread throughout Australia, and during the late Pleistocene ice age, they used land bridges to invade North to New Guinea and south to Tasmania.
Early taxonomic studies of thylacines were limited by barren fossil material, and the study was relatively cramped. Early scholars, based on many detailed features on their teeth, believed that the thylacine was evolutionarily closely related to another class of carnivorous marsupials that had become extinct in South America, the thylacine. However, in later studies, especially studies of foot bones, it was proved that the thylacine was more closely related to the possum ferret, and this conclusion was widely accepted.
The extant Possum, which is very similar to the early fossilized thylacine. Image source: See watermark
Limited by the reality of insufficient fossil material, the origin and evolution of thylacines are still controversial, which may also prove that the evolution of thylacines may be more complex than we previously thought. Some scholars support that the thylacine is a member of the backbone of the Order Dasyuromorphia and that the Tasmanian devil is a close biological relative. However, findings published in Genomic Research in January 2009 suggest that marsupial anteates may be closer to the backbone members of the Tasmanian possum than Tasmanian devils and more closely related to thylacines.
The thylacine looks like a dog and has a "wolf" in its name, which is actually very different from a real wolf. One of the characteristics that distinguishes the skull of the canine-headed thylacine from other fossil thylacines is the increased gap between the canine teeth and the premolars, which leads to the elongation of its snout, which makes its skull look more morphologically similar to that of canines than possums, but this similarity is only the result of convergent evolution, that is, the evolution of functionally similar structures in groups with very distant lineages. They still have very clear differences in the skull and teeth.
Left: Thylacine skull (Image: Author); Right: Gray Wolf skull. Image source: krissyfawx.deviantart.com
The difference between teeth is the most significant. The thylacine has a total of 46 teeth, unlike the 44 in a typical euphropod. Thylacines have 4 pairs of incisors on each side of the upper jaw, and typical true mammals should have 3 pairs of incisors per side of the upper jaw. Interestingly, the incisors of the thylacine are not staggered up and down like dogs, but the upper incisors are to cover the lower incisors. Their lower canine teeth also do not protrude in front of the maxillary canine teeth when bitten, but in a groove with a strong recess in the palate between the incisors and canine teeth. Another difference is that the buccal teeth of the thylacine are 3 premolars and 4 molars on each side, while the opposite is true for typical true animals, with 4 premolars and 3 molars on each side.
In the canine family, the meat is cut by the split teeth, the 4th premolar and the 1st inferior molar. The 1st and 2nd upper molars and the 2nd and 3rd lower molars are mainly responsible for chewing and crushing functions. This functional differentiation of teeth allows canines to concentrate more on cutting meat or biting bones in one place, while felines, which we are more familiar with, give up all their chewing ability, and their 1st upper molar degenerates into a remnant, and the lower 1st molar is responsible for chewing and crushing the part completely degenerated, preserving only the cutting function. That's why wolves and domestic dogs can nibble and chew bones, while felines don't.
But the case is a different case for the equally highly carnivorous thylacine, whose cleft teeth do not include the premolars, but are all made up of molars. The upper and lower molars of the thylacine are morphologically very similar to the split tooth structure of the canine family, but there is no such thing as a cat and canine that are completely specialized and responsible for cutting or chewing, and all the split teeth have maintained a fairly consistent shape, the main difference is only a slight size difference. Functionally, all teeth retain both crushing and cutting capabilities.
This tooth structure of the thylacine has not changed much in evolution except for the gradual development of cutting function. This is confusing because it doesn't seem to be in line with the principle of efficacy, and the thylacine is obviously more dispersed when biting, rather than the canines can concentrate on one point. But this structural feature apparently did not affect the survival of the thylacine, such a tooth structure may indicate that the thylacine can chew and swallow the flesh and small pieces of bone when eating, but the processing speed may not be very fast. This may improve their use efficiency for small and medium-sized prey, but because they need to chew repeatedly, their eating time may be extended. Such a way of eating may not only limit the main hunting object species and feeding patterns of thylacines, but also vaguely provide some clues to study the hunting patterns and success rates of thylacines.
You can still see its face, but it is difficult to know its behavior
Thanks to the very well-preserved dried corpses, furs, and stuffed specimens of the thylacine in the museum, as well as a large number of text descriptions, black and white photographs, and video data of captive individuals, we can understand the morphology of the thylacine very accurately. Overall, the thylacine resembles a short-headed dog with a flat torso and a slender, stiff tail, and especially the head shows some dog-like appearance characteristics.
Adult thylacines are about 100 to 130 cm long, 50 to 65 cm long at the tail, about 60 cm high on the shoulders, and weigh about 20 to 30 kg. The difference between the sexes is not obvious, only that the male is larger than the female in the average body size. The thylacine has four toes on both front and back feet, lacks thumbs on its forelimbs, and its claws cannot be retracted. The pubic bone is highly degenerate and is represented only as cartilage. Males have a scrotum pouch similar to a nursery bag that can be retracted to provide protection when crossing complex environments such as shrubs or fighting, and the female has a pouch with an opening backwards, with two pairs of breasts.
The main breeding seasons for thylacines are winter and spring, but breeding is possible throughout the year. The only successful breeding in captivity occurred at Melbourne Zoo in 1899, and the lifespan of wild thylacines is about 5 to 7 years, and the lifespan of captive breeding can be up to 9 years. The thylacine has soft and dense short hairs all over its tail, and the fur color varies from earthy gray yellow and gray yellow to bright brownish yellow, and has 13 to 21 black stripes from the back to the tail, and one stripe on the thigh is obviously longer than other stripes. There are changes in the color shade of these stripes, and changes in body color and stripes are often considered to be the result of changes in different age stages, and the body color of elderly animals tends to be dull and the texture is faded. The stripes remind the witness of the Asian tiger, which is also the origin of the popular pseudonym for the thylacine: tasmanian tiger.
Left: Thylacine specimen; Center: Thylacine skin Zhang; Right: Thylacine corpse. Image credit: allyouneedisbiology.files1, au.pinterest.com, wordpress .com
According to written records, thylacines prefer dry forest environments, swampy wastelands and grasslands, and in Tasmania, thylacines live in the northern and eastern coastal areas and the central plains, but they clearly avoid the southwestern mountains and dense rainforests. They prefer to move in the twilight-night time segment and retreat back into woodland or bushy areas during the day. Survival patterns of thylacines may include solitude, pair activities, or small-scale family-based colonies, and in some cases thylacines from different families will colonize, which may be some form of social activity. Depending on the documentation, it is shown that the thylacine may emit an indescribable smell when it is emotionally excited. In the only black-and-white video and some photographs, the thylacine can be seen always opening its mouth in a puffy manner, which is usually considered to be a nervous or threatening behavior of the thylacine.
Thylacines may exhibit nervous or threatening behavior. Image credit: allyouneedisbiology.files
Thylacine prey is very extensive, including wallabies, wombats, small and medium-sized reptiles, and small to large birds (including emus), but their main diet is small kangaroos. Carnivorous mammal bite force studies have shown that thylacines have the ability to catch medium to large prey, but there is no direct evidence for such a conclusion. They also sometimes eat carcasses, and captured thylacines eat dead rabbits, sheep and beef.
Their palms and metatarsals are distinctly short and their dorsal spines are stiff, suggesting that the thylacine is not particularly agile and running at high speeds, and is often described as "inflexible and slightly clumsy", and in some cases the thylacine uses its hind legs to jump like a kangaroo. The short limbs allow the thylacine to obtain higher speeds in a short distance, which is very important in raids or ambush hunting behaviors, and hunters who have set traps have reported that "thylacines like to ambush prey". But in other descriptions, thylacines hunt on a family scale and show amazing endurance and strategy in chasing prey, i.e. some have described a thylacine group divided into pursuits and ambushes. This description can also be corroborated by a study of the brain of the thylacine, that is, the brain of the thylacine has a more developed caudal nuclear cortex, and this structure is responsible for learning, planning and decision-making, which shows that the thylacine has a strong ability to plan and solve problems, which is important for communication in social animal life and hunting.
But these are only guesses. In fact, in addition to understanding the appearance and morphology of the thylacine, we know very little about the animal's habits and behavior. A large number of descriptions of the behavior of wild thylacines are eyewitness reports and some written descriptions from hunters, farm employees and travelers, and the accuracy of these written materials is currently impossible to verify, but can only be used as a reference. Our small number of exact observations of thylacines also come from zoo captive individuals, but these observations are usually carried out during the day, in the zoos of the age and environment at that time, the thylacine may be under great pressure because of its personality and living conditions, and some of the behaviors shown in the known film are considered to be atypical behaviors or stereotyped behaviors, so these observed behaviors may not represent their real behavior patterns.
The beginning of the end of the thylacine
Europeans were not the first humans to come into contact with thylacines, but the Indigenous peoples of Australia were. Petroglyphs created by indigenous peoples based on thylacines have been found throughout almost all of Australia. According to some petroglyphs, it is certain that at least some indigenous tribes have hunted thylacines and used them as food. During the Late Pleistocene, the thylacine that invaded New Guinea was the first to become extinct, and the reason for its extinction is unclear. The extinction of the native thylacine on the Australian continent occurred about 3,000 years ago. Conventional wisdom holds that the Australian Aboriginal Canis lupus dingo led to the extinction of the thylacine on the Australian continent through direct competition, but it is really difficult to assess how much responsibility the Australian Aborigines and Australian wild dogs are responsible for the extinction of the indigenous thylacine in the australian continent.
The thylacine in Australian prehistoric petroglyphs. Image credit: au.pinterest.com, fanpop .com, hubpages .com
According to the analysis of the habits of the Dingo, it does not appear that there will be direct competition with the thylacine. The Dingo is mainly active during the day, although the bite force is small, but the skull can withstand more pressure, it can hunt small and medium-sized animals, but also often attack medium and large animals, and the Australian wild dog can also ingest some plant foods, is a typical omnivore. The thylacine, on the other hand, is mainly active at night and hunts mainly small animals. Moreover, the size and weight of the thylacine are larger than the Dingo, and if the thylacine encounter is one-on-one, the thylacine has a greater chance of victory.
A pair of dingoes. Image source: See watermark
However, sub-fossils of thylacines have been found in many areas where the Australian wild dog is active, which shows that their living environments do overlap, so we must not rethink the reason why the Australian wild dog replaced the thylacine, two of which may play a very important role, one is the gregarious mode of the Australian wild dog, and the other is the stronger breeding ability of the Australian wild dog.
The social size of the Australian wild dog is usually 3 to 12 heads, while the group size of the thylacine is usually a pair of individuals or a pair of individuals with 1 to 3 pups. That is to say, in most cases, if the two encounter, although the thylacine can compete with the dingo in a one-on-one situation, it is often significantly inferior to the opponent in number when the group meets. The gap between the two is more obvious in terms of reproductive ability, although the thylacine has two pairs of nipples, but the reproductive capacity per litter is generally only 2 to 3 pups. The Australian wild dog is 1 to 10 litters, mostly 4 to 5 litters. The juveniles of the thylacine are believed to live in the mother's nursery bag for 3 months, and after leaving the nursery bag, they must grow to half the size of an adult individual to be independent. The Dingo puppies can act independently for 3 to 4 months, which shows that in terms of group care for young animals, young animal independence, etc., the thylacine has once again lost to the Australian wild dog. In summary, the thylacine may not have lost in direct competition with the dingo, but in breeding and herd patterns. It is likely that the Dingo will gain a numerical advantage and put increasing pressure on the thylacine to survive with a faster breeding, which will eventually cause it to disappear from the australian continent.
When the thylacine disappeared from mainland Australia, the thylacine was found only on the island of Tasmania. The natives of Tasmania would occasionally hunt thylacines, then strip out the bones and make a strange little lid or something like a small house on top of the bones, believing that if the rain fell on them after it was done, then there would be very bad weather.
This capture did not affect the survival of the thylacine here. Perhaps the thylacine could have survived quietly on the island, but unfortunately the Europeans discovered the island.
Probably stemming from the psychological projection of people's traditional evil impressions of wolves, people who live and graze in Tasmania also believe that thylacines are a group of meat-eating and blood-sucking guys, and more and more people are rumored to have seen thylacines attacking livestock, sucking blood and eating meat (although it is not excluded that such things have happened in small quantities, but there is no direct evidence). Rumors intensified, and when people believed that the important grazing asset sheep were attacked in large numbers by thylacines, the Europeans could not sit still!
A photograph of a supposed thylacine attack on poultry is now thought to be a posing photo of a chicken stuffed into the mouth of a thylacine specimen. Image source: hauntedauckland.com
Initially a small number of private killings of thylacines close to farms or houses, some local companies have since begun to publicly introduce hunting bounties along with local governments, with Tasmanian officials saying that hunters receive £1 for every adult thylacine killed and 10 shillings for killing a cub. Hunters, including farmers and bounty hunters, then did their best to culling the thylacines.
During the bounty hunt, the Tasmanian government paid a total of £2,184, estimating that at least more than 2,200 thylacines were killed, but it is widely believed that the number of thylacines killed far exceeds the corresponding number of bountys, because a large number of adult thylacines who escaped from injuries may die on the way to escape or in the nest, and the mass killing of adult beasts may also lead to the death of some young who cannot leave the nest. In addition, the reasons for the rapid disappearance of the Tasmanian thylacine include the destruction of the living environment, the continuous decline in the type and number of prey, the survival pressure brought by domestic dogs, and the collection needs of overseas collectors for thylacine specimens.
Australians show hunting thylacines. Image source: nnimgt-a.akamaihd.net, abc.net.au
After noticing a significant decrease in the number of thylacines, since 1901, a number of nature conservation teams have proposed to protect the thylacines, but unfortunately they have not been successful. It was not until 1928 that the Tasmanian Advisory Committee first proposed the establishment of protected areas to protect the increasingly rare thylacine, but as mentioned in the opening chapter, the government did not issue an administrative protection order for thylacine until 10 July 1936. By this time it was too late.
After the death of the last known thylacine, the thylacine went from being an abominable sheep killer to a precious endangered animal in the public and official sight, and people began to collect and search for any evidence that the thylacine still existed, and some sightings and encounters showed that there may have been very few thylacines in the northwestern part of Tasmania until around 1960, but there is no definite direct evidence of this. When a species has not been proven to be found in its original habitat for more than fifty years, the conditions for declaring "extinction" are met. Under this provision, the identity of the thylacine "endangered animal" was automatically changed in 1986, and the IUCN officially announced to the outside world: the first thylacine, confirmed extinct in Australia.
Behind the thylacine, the red dust phantom
Since the death of the last known thylacine in 1936, there has been an outbreak of thylacine sightings in Australia. The Rare Animals Society of Australia has reported more than 3,800 sightings and the Australian Centre for The Study of Mysterious Animals has also reported more than 130 sightings, surprisingly not only in Tasmania, the last refuge of the thylacine, but rather a large number of sightings in mainland Australia, with the most frequently recorded sightings in southern Victoria. Since then, and into modern times, sightings in these areas have continued to occur, and the scope of sightings has once again expanded to New Guinea, as if the soul of the thylacine is so fond of teasing people that it is haunting but untraceable.
A large number of these sightings have occurred in densely populated living areas, urban and rural suburbs and resorts. It's very interesting that an animal that is considered extinct is not rediscovered in inaccessible and suitable habitats, but always appears in full view of the public, where the original living environment has been destroyed, and seems to be very easy to catch by people's cameras or eyes. And no matter how advanced the technology is, how the cameras in people's hands are replaced, people will never be able to take clear photos or videos to prove that they have seen a living thylacine.
People always believe in their eyes, firmly believe that what they see is the truth, but ignore a saying that clearly tells us, that is, "the heart thinks, the eyes see." When people are keen to find something, they can always find its traces, if they see only uncertain and vague forms, people will unconsciously make up "it" is the truth they are looking for. This is also the reason why many modern extinct animals or water monsters always find nothing during scientific expeditions, but tourists and travelers can always see and photograph in a short period of a few days. So far, no photos and videos of the rediscovery of the thylacine have been confirmed as authentic. That's probably why Australian officials are indifferent to these ongoing sightings.
But there are always surprises, and the recent thylacine expedition on the Cape York Peninsula began with years of continuous reports of suspected thylacine activities by former national park employees, wildlife survival experts, and indigenous peoples. The news caused a heated debate, with attempts to explain the legitimacy and irrationality of this official act from different angles.
The Cape York Peninsula was once the traditional habitat of the thylacine, but living here in the past does not mean that it still exists, after all, it is believed that the thylacine has disappeared from the Australian continent for three thousand years. But one of the more favorable conditions is that the Cape York Peninsula is too remote, almost untouched, very little affected by human activities, and most of the environment is still very suitable for the habitat of the thylacine. In addition, the total area of the peninsula is about 120,000 square kilometers, but the population is only about 18,000, most of which are indigenous peoples. There are no asphalt roads, only very bumpy dirt roads. The climate is dry and the rainy season is clear, only the dry season can be entered by car, and once the rainy season is entered, no vehicle can enter. In other words, the Cape York Peninsula has all the conditions for a thylacine shelter. In addition, from some introductions, it can be seen that in addition to the natives, the witnesses also have national park employees and wild survival experts with high scientific literacy and more cautious attitudes, some of whom are very low-key and refuse to be exposed, and are extremely cautious about their own sightings. This is obviously different from the witnesses who often shoot "thylacines" in suburban resorts or tourist spots and then make a lot of news, and the credibility of the former's testimony will be higher in terms of credibility. Moreover, the direct and public announcement of Australian official involvement also shows that the credibility of sightings and reports in this region is not as high as before.
Phantom of Red Dust. Image source: Author
Although the Cape York Peninsula is enough to play the role of a shelter, 120,000 square kilometers is also large enough for the thylacine, but whether there is a sheltered thylacine is another problem, the canine-headed thylacine that disappears under the muzzle of the gun, and has been entangled in people's deep thoughts for decades, will they once again appear in the rolling red dust of the Australian continent, or will the faint figure dissipate again? No one can say anything until the expedition is over. While one hopes that the expedition will come as a surprise, it is indeed impossible to be blindly optimistic decades after the worst-case scenario. After all, there is still a gap between the story and reality, in the words of my friend, "Don't have too much hope for this matter, but don't hold out hope."
Edit: You Zhiyi
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