How Megalania and Other Giant Lizards Were Able to Survive Until Very Recently

since the dinosaurs have gone extinct there has been a general trend of mammals taking over in ecosystems across the world and for the last 2 million years or so the world's large predator niches have been dominated almost exclusively by mammals but up until as little as 50,000 years ago during the Pleistocene when Ice Age giants were roaming the northern hemisphere and African beasts were occupying the savannas a giant lizard was able to cling on as one of Australia's main terrestrial predators in the first half of the Cenozoic just after the dinosaurs had gone extinct there were still notable large reptiles that were often the largest predators in their habitats in South America there was titanoboa they car-sized turtle carp on amis and in Europe there was the praça das that had specialized to living on land but about 45 million years ago the large reptiles started to go extinct and mammals took their place during the Eocene the earth's temperature started getting cooler and this trend would continue for millions of years as the climate became colder and drier the rainforests of the Eocene retreated to the equator being replaced with grasslands and drier forests this new climate suited mammals significantly more than reptiles as being warm-blooded they were able to stay active for longer in cooler climates but also as the ecosystems were becoming less forested their superior respiratory systems would have seen them fare better / grasslands meaning that large reptilian predators were confined to the rivers and lakes however 40 million years later meg Alania a giant predatory land reptile appeared in Australia meg Alania was very big although estimates have varied in recent years large ones were probably able to grow to the lengths of 5 metres and yet it was living at a time when the rest of the continents large land predators were mammalian Meg Alania will monitor lizards and this may be one of the reasons they were able to compete with mammals in their ecosystem as monitor lizards of the last living large reptilian land predators and can hunt in the same habitats as large mammalian predators for instance the Nile monitor can commonly grow to around one and a half metres long and is found all over sub-saharan Africa alongside big mammals one reason they are able to do this is that monitor lizards can eat very all decaying meat without getting sick to such an extent the Komodo dragons are known to dig up graves and eat dead people due to this it is highly likely that meg Alania was able to exploit food sources that's other predators it may have sometimes come into contact with like the marsupial lion would have not been able to take advantage of all so unlike any other reptile alive today monitor lizards are able to run for extended periods of time all rap tiles apart from crocodiles have three chambered hearts which means that some oxygenated and deoxygenated blood can mix at certain points while the heart is pumping which makes the process inefficient and means that reptiles often tire easily in comparison the four chambered hearts of birds and mammals keeps the oxygenated and deoxygenated blood completely separate to stop this from happening monitor lizards are subjected to the same three chambered hearts of all known crocodilian reptiles for the sections of their hearts are pumped at very different pressures greatly reducing the amount of blood mixing and this makes their heart superficially act like a four chambered heart due to this adaptation among others it is the consensus that monitor lizards are capable of the highest metabolic rates out of any living reptile and they use this to great effect in fact their hunting strategies are reminiscent of the active pursuit techniques employed by similar sized mammals the Parenti the largest living Australian lizard is capable of hunting and catching speedy mammals like rats and rabbits and on occasion can even catch birds and if Meg Alania was capable of the same speedy pursuits as its cousins then it would be a formidable hunter of the marsupial herbivores even out in grasslands or plains although it is unclear what their closest relationships with the monitor lizards was it has been suggested that they may be related to the Parenti due to similarities in their skull shape however the most popular theory now is that they are related to Komodo dragons and this makes sense seeing as the historic range of Komodo dragons was much larger stretching throughout Indonesia and across northern Australia and they may have even originally evolved there so Australia was home to two giant species of lizard and there was even another large reptile called Queen Carla there was a land crocodile and could commonly grow to the size of a komodo dragon but one species may have grown considerably larger meaning that three out of the four large predators in Pleistocene Australia were reptiles when the rest of the world was dominated by mammal because of this mega Lanie revolving in Australia likely has something to do with the continent itself as well Australia is the driest place on earth barring Antarctica with 2/3 of the continent either being deserts or highly arid the lack of rainfall creates poor conditions for plant life among much of the country which means less mammalian herbivores can be supported here than in other areas of the world there were some large animals that would have lived here at the same time as Meg Alania like Diprotodon which was basically a one ton one bat and Prokop Sudan which was a very large prehistoric kangaroo however herbivore seemed to have been smaller and less diverse than in other parts of the world during the Pleistocene this is because mammals have large brains and are warm-blooded which require a loss of energy and so need to eat a lot every day to satisfy these needs as there were less prey animals around it would have been harder to support large mammalian predators for the same reason yet despite lacking in large herbivores Australia's of reptiles paradise with the highest number of reptile species compared to land area than anywhere else in the world and this is because reptiles have far less taxing energy requirements than mammals due to being cold-blooded and having slower metabolisms the Komodo dragon for instance is able to eat a very large amount of food in one sitting up to 80% of its body weight and then not need to eat again for up to a month and what potentially makes reptiles inferior to mammals in other parts of the world was their strength in Australia and so an animal like Meg Alania or Queen Connor may be better suited predators for Australia than a mammalian one also as reptile diversity was higher than mammal diversity in this part of the world where it is usually the other way around means that there was a higher chance that the large animal niches would be filled by reptiles it has been hypothesized this is the reason behind why Australia has so many venomous species as venomous animals don't need to expend much energy to catch their prey whereas a lion for example needs to chase an animal running at top speed and then wrestle it to the ground a venomous animal like certain species of snake merely need to get a good bite and then go and find the animal after has died and Meg Alania may have been venomous also as it has thought that their closest living relatives are Komodo dragons there is a high likelihood they may have shared their venomous bite there are glands in the mouth of Komodo dragon that excrete anticoagulant hemotoxin that would stop the victims blood from clotting and greatly increases the chance of them dying of blood loss this adaptation is put to great use by Komodo dragons today that are able to take down water buffalo animals that can be six times their size this means that meg Alania would have been able to kill large prey like a diaper to don without expending too much energy unfortunately most likely due to a combination of humans arriving in Australia and Indonesia combined with climate change the mega Lai Nia went extinct and the historic range of the Komodo dragon was shrunk down to a fraction of its original size making the islands of Komodo and Flores the last places in the world where the terrestrial reptile as their main predator thank you for watching if you enjoyed the video and would like to be notified of future uploads then consider subscribing many thanks to my patrons for supporting me especially Fuzzle Worth and Green Falls if you would like to support me as well then you can go to patreon and make a pledge you

Channel: Moth Light Media

Views: 94,843

Rating: 4.9648824 out of 5

Keywords: Megalania, Giant Monitor Lizard, Giant Lizard, Giant Reptile, Why Megalania, How Megalania Survived, Komodo Dragons, Australia, Australian animals, Australian, Prehistoric Animals, Prehistoric Australian Mammals, Australian Megafauna, Reptile Apex Predator, Apex Predator, Evolution of Megalania, Australian Climate, Nile Monitor Lizards, Perentie, Diprotodon, Giant Kangaroo

Id: lEyXgHGId_c

Length: 8min 2sec (482 seconds)

Published: Thu Dec 05 2019