When Giant Hypercarnivores Prowled Africa

When Giant Hypercarnivores Prowled Africa

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we'd like to thank rake on wireless earphones for supporting PBS in 2013 a researcher working in the vast collections of the National Museums of Kenya made a surprising discovery tucked away in a cabinet marked hyenas he noticed a large fossilized lower jawbone from some kind of carnivore and it was big much bigger than the jawbone of a lion the largest carnivore in Africa today six years later it was revealed to the public as an enormous beast that was completely new to science it was named
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Simba kuba who toko Africa and while it's name literally means big lion from Africa and Swahili this creature was not a big cat and even though it was found in a drawer labeled hyenas it was not a hyena either it was a hyena dot an extinct family of carnivorous mammals that lived from the Paleo scene to the Miocene epoch and it lived in Africa Europe Asia and North America but Simba Kubo was not only unique because of its large size the fossil jawbone was excavated in the late 1970s at a site
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called mess web bridge in western Kenya that dates back to about 26 million to 23 million years ago it was from this jaw bone that researchers were able to estimate a range of potential body sizes for Simba Kubla based on the size of its molars and comparisons to living carnivores and it looks like at its smallest Simba kuba was probably the size of a large lion and at its largest it could have been larger than a polar bear and it was a hyper carnivore meaning that it got more than 70% of its calories for meat based on its age in
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its monstrous size Simba kuba is the oldest known Giant member of its subfamily of hyena dots these hyena dots gave the world some of its largest terrestrial carnivorous mammals ever known and while these behemoths were the apex predators of their time they're not around anymore it turns out that becoming the biggest baddest beast on the landscape can have serious consequences when that landscape suddenly changes hyena dots are members of an extinct order of carnivorous mammals called the Creedence and even
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though they were super carnivorous Creedence evolved independently from the order Carnivora which includes all modern feel its canids and other critters cRIO dons are older and more primitive than carnivory and they look different too their skulls were low with small brain cases and their limbs were generally short and heavy early on in their evolutionary history about 65 million years ago the crea dots branched into two lineages one of which was the hyena dots but the exact place they arose is still kind of a mystery some
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experts think they originated in Africa others say Asia and some suggest both with a distinct group of hyena dots evolving on each of the two continents but the fossils and the phylogenetic evidence we have seemed to suggest that they arose somewhere in Eurasia and Simba quba was part of a subfamily called he'e nalu Rene this particular group probably originated in the region known as afro Arabia which includes the whole Arabian Peninsula and northern Africa around 48 million years ago from there they spread into Europe Asia and
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North America where their large size and powerful bite ensured their position at the top of the food chain but by the middle a legacy in roughly 30 million years ago it looks like they went extinct on the northern continents maybe due to competition from other groups of carnivores that evolved during that time but in afro Arabia they persisted evolving an isolation separated from the newly evolved carnivores in Eurasia by a Seaway and this isolation could have contributed to the rise of giant hyena dots like Simba Kubla because it wasn't
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until the early Maya scene around 23 million years ago that evidence of the largest members of this group appeared approaching the size of modern-day rhinoceros well we know about Simba Quba and its close relatives comes from a very fragmentary fossil record which is mostly made up of dental remains and a few bones from the rest of the skeleton this limited fossil record has made it hard to figure out what their family tree or even they themselves looked like what we do know from their teeth is that these hyper carnivores had to be able to process a lot of meat which they did
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with specialized teeth called carnassial's these are modified premolars and molars with self-sharpening edges that pass by each other in a shearing motion like a pair of scissors now living carnivores usually only have one set of these scissor-like teeth but Simba Koopa and its relatives had three turning their jaws into meat slicing machines but making sense of the rest of their anatomy is kind of hard in order to sink those teeth into all that meat they had to catch it first so researchers are really interested in
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figuring out how these giant predators moved around and the one clue we have about Simba Kubo's locomotion is pretty intriguing many modern carnivores are digitigrade walkers this means that they walk on their toes with their heels in the air making them faster than plantigrade walkers like us who walk with the soles of their feet flat on the ground digitigrade carnivores are more common in open grassland environments where that posture helps them save energy and increases their stealth speed and hunting success and Simba Kubas
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well-preserved heel bone called the calcaneal was similar to that of one of its relatives which has been reconstructed as semi digitigrade not all the way up on its toes but not totally flat-footed either researchers also think that relative was capable of making powerful leaps so based on similarities between the two heel bones it's possible that Simba kuba was also semi digitigrade making it faster and a more agile hunter all of these advantages a large body three sets of meat slicing teeth and the ability to
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get around quickly probably led to the success and survival of the hyena dots through the Miocene epoch they likely hunted really large herbivores like the relatives of modern elephants and rhinos occupying a niche that remains vacant today but if they were such powerful beasts that were so well adapted to their ancient landscapes then why aren't they still around well the hyena dance met their demise by the end of the Maya scene around five million years ago thanks to an even more powerful force a rapidly changing environment this period of change
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started back around 23 million years ago as the Arabian Peninsula approached Eurasia closing the Seaway that had kept Simba quba and its relatives separated from the carnivores of Eurasia from then on waves of animals were able to migrate back and forth between the two regions and among these migrants were hyena dots from afro Arabia heading north and carnivorans from Eurasia heading into Africa this exchange of animal populations happened at a time when earth was undergoing major changes like the formation of the East Africa riff system where two parts
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of the African tectonic plate started to move away from each other these changes led to dramatic transformations in the afro of Ray bian landscape with forests becoming drier and turning into more open habitats all of these changes spell disaster for the hyena dance but researchers are still trying to figure out exactly how there are currently two hypotheses for the extinction of Simba Koopas group changing food webs as environments changed and large herbivores disappeared or competition from modern carnivorans the first one
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suggests that when the environment started to change it was bad news for the large herbivores that hyena Don's relied on large herbivores tend to reproduce slowly which can lead to a rapid decline in numbers if ecosystems change too quickly because they can't adapt fast enough fewer large herbivores meant less food for the large hyena dots which weren't adapted to hunting smaller prey this would have made hyena dance more vulnerable to extinction than the smaller carnivorans which had a broader diet the second hypothesis involves
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competition from members of the order Carnivora as they move from Eurasia into afro Arabia around 23 million years ago up to that point hyena dance had been dominating the predatory niches in afro Arabia fossil evidence suggests that the earliest afro Arabian carnivorans were pretty small mezzo carnivores animals that get at least half of their calories from meat and the rest from other things think like raccoons or coyotes and they're usually less dramatically affected by environmental changes than large hyper carnivores are so as new
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carnivorans dispersed into africa from Eurasia they became more diverse and started to compete with the hyena dots plus carnivorans with complex cooperative behaviors like living in packs may have been able to steal prey from lone hyena dots between the changing environment lack of food and the introduction of smart and sneaky competition Simba kuba and its relatives might have simply met their match after succeeding on three continents for at least 15 million years the evolution and extinction of these hyper carnivores offers rare insight
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into a time that saw massive changes in the climate oceans tectonic activity and the dynamics of mini ecosystems and as more fossils are found we may be able to recreate and better understand the African landscape in which they lived which is also the landscape where our early ancestors evolved ultimately the giant hyena dance of Africa serve as a stark reminder that even the most powerful beasts are no match for a changing world thanks to Ray Khan for supporting PBS Digital Studios break on
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makes wireless earphones that come with bluetooth pairing a portable charging capsule in six hours of play time instead of traditional single channel distribution ray con uses true wireless audio which uses independent frequencies for the left and right channels ray khan's latest e 25 model comes in six different color options every ear is different so Ray Khan has six differently sized gel tips designed to fit any size with a noise isolating fit and no wires or stem the earphones are sweat resistant too if working out is
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your thing for more information go to buy recon comm slash Aeons I hope you enjoyed this episode of Keeping Up with the Kardashians but I've always got to give a shout out to this month's Yount ologist Patrick Seyfert Jake Hart John Davidson Ian and Steve go pledge your support at patreon.com slash yawns and become an e on ight and also thanks for joining me in the Konstantin Hustlas studio if you like what we do here then subscribe at youtube.com slash yawns [Music]
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