originally published at Sport -
Researcher’s fossil evidence disputes cold water Megalodon theory, suggests the largest sharks came from temperate climates and were breeding females.
— Max Hawthorne
BUCKINGHAM, PA, US, May 23, 2022 /EINPresswire.com/ — Award-winning author and independent paleontologist Max Hawthorne, best known for his Kronos Rising series of sci-fi thrillers, is also a bit of a Megalodon junkie. Several years ago, Hawthorne “made waves” with his radical Megalodon Scavenger Theory, suggesting that, as the extinct mackerel shark became bulkier and more cumbersome over the course of its ontogeny, it gradually transitioned from a primary predator and opportunistic scavenger to a primary scavenger and opportunistic predator.
Hawthorne has come forward in response to a recent study by the University of Chicago, which suggests that the biggest Megalodon sharks were found in higher latitudes and colder climates, whereas the smallest ones came from lower latitudes and warmer waters. It also suggests that more temperate locations traditionally believed by researchers to be Megalodon nurseries may not have been. The teeth believed to be from baby Megalodons may simply have been from sub-adults.
Hawthorne believes there are potential holes in the theory, based on a plethora of fossils from his personal collection. “I find myself in disagreement with portions of the ‘cold water giants’ theory,” he stated. “For examples, I own several tiny Megalodon teeth from the Hawthorn formation of North-central Florida. They’re 5-12 million years old. One anterior tooth has an enamel height of less than .75 inches which, per traditional formulas, suggests a newborn shark. We’re also talking a lower latitude and a still-warm climate. That indicates that baby sharks were in that region at that time.”
Another issue Hawthorne has with the cold water theory is evidence he possesses of what may have been the largest sharks ever. “I have an extensive fossil collection, including a section of whale rib with a spectacular gouge from a scavenging Megalodon. You can see where the flared-out cusps of one of its tooth crowns gouged deeper into the rib as the tooth slid between it and the next rib. When you compare that gouge to, say, a six-inch tooth, you see it could’ve never done the job. The shark that fed on this whale had anterior teeth that were likely at least seven inches long. This fossil hails from the Miocene strata of the Lee Creek mine in North Carolina. Granted, that is a higher latitude, but it’s also Lower Miocene, which means overall temperatures were hotter.”
The question of tooth size in the adults, is, for Hawthorne, the big fly in the ointment. “It used to be that, if you had an impressive lateral or posterior tooth and wanted to do a size estimate of the tooth’s former owner, it was difficult; there were no complete Megalodon jaws. Now there are two, CB-11 and CH-31, both of which have 46 teeth,” the author stated. “I have in my possession an assortment of massive posterior teeth. By scaling them up based on the matching tooth in the complete sets, we’re able to get an idea of how big the sharks were. And, of course, we also know where they were when they lost their teeth.”
Hawthorne focused on three Megalodon teeth from his collection. “Before getting into details, let me preface by saying we’re going to use teeth from specimen CB-11 as a reference. It’s the bigger of the two, with the largest anterior tooth (UL1) measuring 146 mm (5.75 inches) in slant height. I’m also going to focus primarily on tooth width for comparisons. I believe it will be more consistent in terms of overall jaw size. Last, but not least, to confirm placement of each of the assorted teeth in the jaw, I consulted with Seth Sorensen, Chief Paleontologist and President of The Fossil Shack and American Fossil. I am extremely grateful to him for loaning me his expertise; his assistance was invaluable.”
Before crunching numbers, Hawthorne touched on locations. “The first of the teeth we’re going to reference is from St Mary’s River on the Florida/Georgia border. It’s Early Pliocene/Late Miocene. That means it’s from a lower (warmer) latitude and a warm-to-cool time period.” In terms of stats, Hawthorne stated, “This is an UR11, meaning upper right eleven, AKA the next to last tooth. The same tooth in CB-11 is 50mm wide. Mine is 66.5mm. That suggests that, scaled up from CB-11’s 146mm, the biggest anterior tooth in the jaw would have been ~194mm in height, or 7.6 inches. A giant female shark.”
His next two teeth both hail from St. Catherine’s Sound in Georgia and are Late Miocene (11.65-5.33mya), suggesting a hot-to-warm climate, with a lower/warmer latitude. “Both of these teeth are a bit disturbing, as they suggest that not only were the sharks in that region huge, breeding females, they may have been the largest Megalodon sharks ever. For example, one tooth is a confirmed UR12 (upper right, most posterior/smallest tooth). In CB-11, that same tooth is 48mm wide. Mine is 69.5mm. Morphological changes notwithstanding, that suggests the largest anterior tooth in this shark’s mouth was 1.45x as wide, i.e., 211.7mm or 8.33 inches. Astonishing. And the last tooth – which, by the way, I have a juvenile version of which was found in the exact same spot – is even scarier. It’s either an LR9 (lower right 9) or an LR10 – it’s difficult to say. The tooth is enormous, 1.42x as high and 1.54x as wide as the #9 tooth in CB-11, suggesting a maximum upper anterior tooth length of 207mm (8.16 inches) scaled up from height, and 225mm (8.85 inches) scaled up from width. If compared to the same tooth in CH-31, it’s even bigger. And I don’t want to even THINK about the possibility of that tooth being an LR10 (which, based on root shape, it may be) because the implications are borderline ridiculous. The bottom line is that these teeth overwhelmingly suggest that the biggest Megalodon sharks we currently have evidence of both swam and gave birth off the coast of what is now the USA. They were in temperate waters, and also in warmer climates.”
Utafiti wa utafiti wa fossil unaonyesha kwamba shark kubwa zaidi zilitoka maeneo yenye hali ya hewa ya wastani na zilikuwa zinazalisha wanawake. Max Hawthorne, mwandishi wa vitabu na paleontolojia wa kujitegemea, anajulikana zaidi kwa safu yake ya Kronos Rising ya thriller za sci-fi, pia ni mraibu wa Megalodon. Hawthorne alianzisha nadharia ya Megalodon Scavenger, ambayo ilionyesha kwamba, wakati papa wa makereli alipokuwa mkubwa na mzito zaidi katika kipindi cha ontogeny yake, hatua kwa hatua alibadilika kutoka kuwa mwindaji wa msingi na mwindaji wa fursa hadi mwindaji wa msingi na mwindaji wa fursa. Hawthorne ametoa taarifa hiyo baada ya utafiti uliofanywa na Chuo Kikuu cha Chicago, ambao ulionyesha kuwa papa wakubwa zaidi wa aina ya Megalodon waliishi katika maeneo yenye joto la chini na maeneo yenye joto la juu. Pia inadokeza kwamba maeneo yenye hali ya hewa ya wastani zaidi ambayo kwa kawaida huaminiwa na watafiti kuwa maeneo ya kuzaliana ya Megalodon huenda yasikuwa hivyo. Huenda meno hayo ambayo yanaaminika kuwa ya watoto wa Megalodon yalikuwa ya watu wazima. Hawthorne anaamini kuna mashimo ya uwezekano katika nadharia, kulingana na wingi wa visukuku kutoka mkusanyiko wake binafsi. "Ninajikuta sikubaliani na sehemu za nadharia ya "watu wakubwa wa maji baridi", alisema. <unk>Kwa mfano, nina meno kadhaa madogo ya Megalodon kutoka kwa muundo wa Hawthorn wa Kaskazini-kati mwa Florida. Zina umri wa miaka milioni 5 hadi 12. Meno ya mbele yana enamel ya chini ya inchi 0.75 ambayo, kwa formula za jadi, zinaonyesha kuwa ni papa mchanga. Pia tunazungumza juu ya latitudo ya chini na hali ya hewa yenye joto. "Hawa ni watoto wa papa ambao walikuwa katika eneo hilo wakati huo, na suala jingine Hawthorne ana na nadharia ya maji baridi ni ushahidi anao wa kile ambacho inaweza kuwa ni papa kubwa zaidi milele. """ <unk>Nina mkusanyiko mkubwa wa visukuku, kutia ndani sehemu ya mbavu za nyangumi zenye madoa yenye kuvutia kutoka kwa Megalodon anayekula taka. Unaweza kuona sehemu ya mgongo wa moja ya meno yake iliyokuwa imeinuka ilichomeka ndani zaidi ya ubavu wakati jino lilipokuwa likipita kati ya ubavu huo na ule uliofuata. Unapolinganisha shimo hilo na, tuseme, jino la inchi sita, unaona kwamba halingeweza kamwe kufanya kazi hiyo. Mbwa-mwitu aliyekula nyangumi huyo alikuwa na meno ya mbele ambayo yaelekea yalikuwa na urefu wa angalau inchi saba. Fosili hii ilitoka katika tabaka la Miocene la mgodi wa Lee Creek huko North Carolina. Kwa kweli, hiyo ni latitudo ya juu, lakini pia ni Miocene ya Chini, ambayo inamaanisha joto la jumla lilikuwa moto. Swali la ukubwa wa meno katika watu wazima, ni, kwa Hawthorne, nzi kubwa katika mafuta. Ilikuwa vigumu, ikiwa ulikuwa na jino la upande au la nyuma lenye kuvutia na ulitaka kukadiria ukubwa wa mmiliki wa zamani wa jino hilo; hakukuwa na taya kamili za Megalodon. Sasa kuna mbili, CB-11 na CH-31, zote mbili zina meno 46, <unk> mwandishi alisema. <unk>Nina aina mbalimbali za meno makubwa ya nyuma. Kwa kupanua ukubwa wao kulingana na meno yanayolingana katika seti kamili, tunaweza kupata wazo la jinsi papa walikuwa wakubwa. Na, bila shaka, tunajua pia mahali walipokuwa walipopoteza meno yao. Hawthorne alizingatia meno matatu ya Megalodon kutoka mkusanyiko wake. Kabla ya kuingia katika maelezo, napenda kuanzisha kwa kusema sisi ni kwenda kutumia meno kutoka sampuli CB-11 kama rejea. Ni kubwa zaidi ya mbili, na meno makubwa ya mbele (UL1) kupima 146 mm (5.75 inchi) katika urefu slant. Mimi pia nina kwenda kuzingatia hasa juu ya tooth upana kwa ajili ya kulinganisha. Ninaamini itakuwa thabiti zaidi katika suala la ukubwa wa jumla wa taya. "Kwa mfano, katika utafiti wa ""Fossil Shack,"" Seth Sorensen, mkuu wa paleontolojia na rais wa The Fossil Shack na American Fossil, alitoa maoni kuhusu jinsi meno hayo yalivyowekwa." Mimi ni shukrani sana kwake kwa kunikopesha utaalamu wake; msaada wake ulikuwa wa thamani. <unk> Kabla ya crunching namba, Hawthorne kugusa juu ya maeneo. <unk>Meno ya kwanza tutakayozungumzia ni kutoka Mto St. Mary's kwenye mpaka wa Florida/Georgia. Ni mapema Pliocene / Late Miocene. "Hii ni kwa sababu ya hali ya hewa ya hewa ya joto, na kwa sababu ya hali ya hewa ya joto, Hawthorne alisema, ""Hii ni UR11, ambayo inamaanisha juu kulia kumi na moja, AKA jino la pili hadi la mwisho.""" Kwa mfano, jino la CB11 lina upana wa 50mm. Mfano wangu ni 66.5mm. Kwa mfano, kwa mfano, kwa CB-11, jino la mbele la mgongo lilikuwa na urefu wa ~ 194mm. Mnyama huyo wa kike mwenye meno mawili ya pili, wote wawili wanatoka St. Catherine's Sound huko Georgia na ni wa Miocene ya Mwisho (11.65-5.33mya), ikidokeza hali ya hewa ya joto hadi ya joto, na latitudo ya chini au ya joto. Meno haya mawili ni ya kusumbua kidogo, kwani yanaonyesha kwamba si tu kwamba papa katika eneo hilo walikuwa wakubwa, wanawake wa kuzaliana, wanaweza kuwa walikuwa papa wakubwa zaidi wa Megalodon milele. Kwa mfano, kuna meno mawili ya UR12 (ya juu kulia, nyuma zaidi au ndogo zaidi). Katika CB-11, jino hilo lina upana wa milimita 48. Ndio maana ni 69.5mm. Kwa mujibu wa utafiti huo, jino kubwa zaidi la mbele la papa huyo lilikuwa na upana wa sentimita 1.45 (mm 211.7). Jambo lenye kushangaza. Na jino la mwisho - ambalo, kwa njia, nina toleo la utotoni ambalo lilipatikana katika sehemu ileile - ni la kutisha zaidi. Ni ama LR9 (chini kulia 9) au LR10 <unk> ni vigumu kusema. Meno hayo ni makubwa, na ni ya urefu wa 1.42x na upana wa 1.54x kama meno ya #9 katika CB-11, na hivyo inaonyesha urefu wa juu wa meno ya mbele ya juu ya 8.16mm (inchi) kwa urefu na 225mm (inchi) kwa upana. Ikilinganishwa na jino lile lile katika CH-31, ni kubwa hata zaidi. Na sitaki hata kufikiri juu ya uwezekano wa jino hilo kuwa LR10 (ambayo, kulingana na umbo la mizizi, inaweza kuwa) kwa sababu athari ni mpaka ridiculous. "Hii ni kwa sababu ""sharks"" kubwa zaidi ya Megalodon, ambayo kwa sasa tuna ushahidi wa, ilisonga na kuzaa pwani ya Marekani." Walikuwa katika maji yenye joto la wastani, na pia katika hali ya hewa ya joto. <unk>