WEBVTT - How Did Allosaurus Work? 0:00:01.920 --> 0:00:07.000 Welcome to brain Stuff production of iHeart Radio, Hey brain Stuff, 0:00:07.040 --> 0:00:11.240 Lauren Vogelbaum. Here between about a hundred and fifty seven 0:00:11.280 --> 0:00:14.840 and a hundred forty five million years ago, Alasaurus, a 0:00:14.960 --> 0:00:19.360 large predatory dinosaur, stopped what's now North America and Europe. 0:00:20.400 --> 0:00:23.599 The fossil record suggests that the beast was pretty common 0:00:24.000 --> 0:00:27.960 and did we mention it was big. Full grown Allosaurus 0:00:27.960 --> 0:00:30.280 could grow to be thirty four ft or ten and 0:00:30.280 --> 0:00:33.560 a half meters long, nine ft or three meters tall 0:00:33.640 --> 0:00:37.720 at the hip, and way around three point two tons. 0:00:37.720 --> 0:00:41.400 Sherlock Holmes creators or Arthur Conan Doyle mentioned the Alosaurus 0:00:41.440 --> 0:00:44.160 by name in his nineteen twelve science fiction adventure novel 0:00:44.240 --> 0:00:48.960 The Lost World. Yet, even giant carnivores take their lumps. 0:00:49.040 --> 0:00:53.280 From time to time, Ladies and gents, meet Big Al. 0:00:54.600 --> 0:00:58.280 A sub adult Alasaurus with a killer nickname big Ol 0:00:58.400 --> 0:01:02.320 lived in what's now North sun Troll, Wyoming. Scientists would 0:01:02.320 --> 0:01:08.280 eventually recover of his or maybe her or skeleton. Look 0:01:08.360 --> 0:01:11.160 closely at the remains and you'll find no fewer than 0:01:11.280 --> 0:01:16.399 nineteen separate bone fractures, and somehow al sustained injuries to 0:01:16.600 --> 0:01:20.880 multiple backbones. Towbones and ribs. There's also evidence of a 0:01:20.959 --> 0:01:25.040 serious infection on the right foot. Big Owl was unearthed 0:01:25.040 --> 0:01:29.679 at a Wyoming quarry. In five years later, fossil hunters 0:01:29.720 --> 0:01:32.800 working in the same state found another Allosaurus skeleton that's 0:01:32.800 --> 0:01:35.920 come to be known as big Al two, and just 0:01:36.080 --> 0:01:39.920 like its predecessor, this specimen was pretty banged up. Many 0:01:39.959 --> 0:01:43.360 of its bones have been fractured or otherwise damaged, only 0:01:43.400 --> 0:01:47.240 to be re healed during the dinosaur's lifetime, although one 0:01:47.319 --> 0:01:50.320 hip injury apparently never healed over and may have been 0:01:50.320 --> 0:01:54.400 implicated in the ultimate demise of Big Al two. Other 0:01:54.480 --> 0:01:58.320 Alosaurus fossils also bear the telltale signs of serious wounds. 0:01:59.000 --> 0:02:01.880 To fully appreciate eate these, we beat take a step 0:02:01.920 --> 0:02:06.520 back and consider the animals role in its environment. Allosaurus 0:02:06.640 --> 0:02:10.840 lived during the Late Jurassic period. Back then, giant herbivore 0:02:10.880 --> 0:02:15.200 dinosaurs called sauropods thundered across the planet, but we often 0:02:15.240 --> 0:02:20.160 find their bones in close association with Alosaurus materials. At 0:02:20.320 --> 0:02:25.080 Dinosaur National Monument, which straddles the Utah Colorado border, there's 0:02:25.120 --> 0:02:28.200 a protected quarry where visitors can look at a jumbled 0:02:28.240 --> 0:02:31.040 collection of fossils that's been lying together for the past 0:02:31.040 --> 0:02:35.760 a hundred and forty nine million years. Besides Allosaurus remains, 0:02:35.760 --> 0:02:39.040 this quarry includes the bones of such long necked sauropods 0:02:39.080 --> 0:02:44.240 as Diplodocus, Camarasaurus, and a Patosaurus. Fossils belonging to the 0:02:44.320 --> 0:02:49.640 unrelated spiky tailed plant eater Steatosaurus are also present. These 0:02:49.680 --> 0:02:53.560 were just some of the vegetarian dinos that Allosaurus interacted with, 0:02:54.320 --> 0:02:57.520 and there was competition at the buffet line. One of 0:02:57.520 --> 0:03:00.880 its rival predators in late Jurassic North Amera Rica was 0:03:00.919 --> 0:03:04.560 the Seratosaurus, a horn nosed carnivore that could grow over 0:03:04.639 --> 0:03:07.920 nineteen feet or six meters long, and which had a 0:03:07.919 --> 0:03:10.880 short cameo in the movie Jurassic Park three from two 0:03:10.880 --> 0:03:16.000 thousand one. Compared to some other dinosaurs, Alisaurus had a 0:03:16.000 --> 0:03:19.480 weak bite force. The bite of a Tyrannosaurus rex, the 0:03:19.600 --> 0:03:22.560 famous carnivore that evolved tens of millions of years after 0:03:22.600 --> 0:03:26.440 the last Allosaurus died out, may have been four times stronger. 0:03:27.919 --> 0:03:32.880 Even so, Allosaurus performed well under pressure. Mathematical models show 0:03:33.000 --> 0:03:35.960 that the beast's head could withstand lots of physical strain. 0:03:37.320 --> 0:03:42.320 In Paleontologists used computer simulations to learn more about how 0:03:42.320 --> 0:03:47.000 this dinosaur dismembered its prey. According to their research, Allosaurus 0:03:47.160 --> 0:03:50.680 may have sometimes behaved like an overgrown falcon at dinner. 0:03:51.760 --> 0:03:55.400 The animals skull was light and its nick muscles were peculiar, 0:03:56.040 --> 0:03:59.520 but with their simulations, the researchers showed Alasaurus would have 0:03:59.520 --> 0:04:02.960 had an see time plucking meat off of corpses by 0:04:03.000 --> 0:04:05.240 grabbing a hunk of flesh and its jaws and then 0:04:05.320 --> 0:04:09.560 yanking its head backwards. The falcons do the same thing today, 0:04:10.320 --> 0:04:14.200 but while those hunting birds have flight ready wings, Alasaurus 0:04:14.240 --> 0:04:18.080 had clawed hands. Noting their size and range of motion, 0:04:18.480 --> 0:04:21.919 dinosaur expert Kenneth Carpenter wrote in two thousand two that 0:04:22.000 --> 0:04:26.000 Allosaurus could use its arms to quote grasp moderately large 0:04:26.040 --> 0:04:30.960 prey and pull it towards the body. So what counted 0:04:31.000 --> 0:04:35.400 as moderately large prey for a ravenous Alasaurus Maybe beaked 0:04:35.400 --> 0:04:39.599 herbivores like the twenty three ft or seven meter Compotosaurus 0:04:39.680 --> 0:04:44.520 fit the bill, or perhaps juvenile sauropods. If Alosaurus hunted 0:04:44.520 --> 0:04:49.400 adults auropods, scientists aren't sure how. Some species alive in 0:04:49.440 --> 0:04:52.279 the late Jurassic were around twenty four to thirty four 0:04:52.320 --> 0:04:56.120 times heavier than even the biggest allosaurus, so the predators 0:04:56.240 --> 0:04:59.760 might not have bothered A few experts think Alasaurus only 0:05:00.000 --> 0:05:04.400 targeted young, sick, or dead sauropods, leaving healthy grown ups alone. 0:05:05.680 --> 0:05:08.480 On the other hand, it's possible that the dinosaur used 0:05:08.480 --> 0:05:11.240 its serrated teeth to rip the flesh off of giant, 0:05:11.360 --> 0:05:15.679 still living sauropods in non fatal attacks. There's a pretty 0:05:15.720 --> 0:05:21.120 awesome name for this hypothetical feeding technique, flesh grazing. A 0:05:21.240 --> 0:05:24.039 bite marks tell Us. Stegosaurus, for one, was on the 0:05:24.040 --> 0:05:28.839 menu only sometimes, though attacking and armored dinosaur might not 0:05:28.960 --> 0:05:33.279 have been the brightest IDEA one Alosaurus pubic bone shows 0:05:33.360 --> 0:05:36.240 a gaping wound that matches the size and shape of 0:05:36.240 --> 0:05:42.480 a Stegosaurus tail spike. Alosaurus has also been suspected of cannibalism. 0:05:42.520 --> 0:05:46.200 A survey that was published in May looked at two thousand, 0:05:46.320 --> 0:05:49.040 three hundred and sixty eight fossil bones, all were covered 0:05:49.080 --> 0:05:54.040 at the same Jurrassic quarry in Colorado, almost tent bore 0:05:54.080 --> 0:05:57.200 the bite marks of meat eating dinosaurs with serrated teeth. 0:05:58.400 --> 0:06:01.400 Many of these not on bones belonged to sauropods and 0:06:01.520 --> 0:06:07.240 other herbivores. However, some of them came from Alasaurus. Since 0:06:07.279 --> 0:06:10.760 Alasaurus is also the most abundant predatory dinosaur found at 0:06:10.760 --> 0:06:13.880 this dig site, it's entirely possible that we're looking at 0:06:13.880 --> 0:06:19.720 evidence of cannibalistic behavior. Also, no discussion about Allosaurus would 0:06:19.720 --> 0:06:24.240 be complete without mentioning Utah's mysterious Cleveland Lloyd Dinosaur Quarry 0:06:24.520 --> 0:06:28.200 or c l d Q. Fossils of ten different dinos 0:06:28.200 --> 0:06:32.400 species have been excavated here, including plant eaters like Stegosaurus 0:06:32.440 --> 0:06:36.520 and a Patosaurus. Yet a remarkable sixty percent of all 0:06:36.520 --> 0:06:39.520 the dinosaur bones found in the quarry were left behind 0:06:39.680 --> 0:06:44.440 by Allosaurus. Altogether, the quarry has yielded parts of at 0:06:44.520 --> 0:06:48.920 least forty six Allosaurus skeletons. Some were juveniles, others were 0:06:48.920 --> 0:06:52.200 full grown adults, but they all died in the same spot. 0:06:52.720 --> 0:06:56.560 And the question is why and why are the numbers 0:06:56.600 --> 0:07:02.200 so skewed? Why is Alosaurus so overrepresented there? Several explanations 0:07:02.200 --> 0:07:05.640 have been put forth over the years. Maybe the c 0:07:05.920 --> 0:07:09.640 l d Q was once a Jurassic predator trap, and 0:07:09.720 --> 0:07:12.720 basically that's a place where herbivores get caught in the 0:07:12.760 --> 0:07:16.640 thick mud or another substance and then attract carnivores who 0:07:16.760 --> 0:07:20.920 die the same way. All those bodies attract even more carnivores, 0:07:21.200 --> 0:07:27.200 with dead and dying predators vastly outnumbering prey species. Critics 0:07:27.280 --> 0:07:29.920 say the rarity of bite marks on the quarries dinosaur 0:07:29.960 --> 0:07:35.240 bones is a strike against this hypothesis, though Another hypothesis 0:07:35.360 --> 0:07:37.800 is that the quarry was the home of a poisoned 0:07:37.800 --> 0:07:41.400 watering hole or a normal one that dried up, leaving 0:07:41.400 --> 0:07:45.320 thirsty dinosaurs to die on its banks, and a third 0:07:45.320 --> 0:07:49.440 proposed scenario blames flooding for the accumulation of the skeletons. 0:07:54.840 --> 0:07:57.600 Today's episode is based on the article Allosaurus was a 0:07:57.640 --> 0:08:00.880 massive flesh grazer and possible cannibal on how stuff works 0:08:00.920 --> 0:08:04.320 dot Com, written by Mark Vancini. Brain Stuff is production 0:08:04.320 --> 0:08:06.480 of by Heart Radio in partnership of how stuff works 0:08:06.480 --> 0:08:09.320 dot Com and is produced by Tyler Klang. Four more 0:08:09.360 --> 0:08:12.040 podcasts my heart Radio, visit the i heart Radio app, 0:08:12.200 --> 0:08:14.920 Apple Podcasts, or wherever you listen to your favorite show.