Scientists have excavated the largest dinosaur ຟອດຊິວ which would have been the largest terrestrial animal on our ດາວ.
ທີມນັກວິທະຍາສາດຈາກ ອາຟຣິກາໃຕ້, UK ແລະ Brazil ນໍາພາໂດຍ University of Witwatersrand ໄດ້ຄົ້ນພົບ a ຟອດຊິວ ຂອງຊະນິດໃຫມ່ຂອງ ໄດໂນເສົາ ໃນອາຟຣິກາໃຕ້ຄິດວ່າເປັນທີ່ກ່ຽວຂ້ອງກັບ brontosaurus. ໄດໂນເສົາ Jurassic ໃນຕົ້ນປີນີ້ມີນໍ້າຫນັກ 26,000 ປອນ, ເຊິ່ງມີຂະຫນາດຂອງຊ້າງອາຟຣິກາສອງເທົ່າ, ແລະຢືນຢູ່ສີ່ແມັດ. ມັນໄດ້ຖືກຕັ້ງຊື່ 'Ledumahadi mafube' ຊຶ່ງຫມາຍຄວາມວ່າ 'thunderclap ຍັກໃຫຍ່ໃນຕອນເຊົ້າ' ໃນພາສາພື້ນເມືອງ Sesotho ຂອງພາກພື້ນທີ່ມັນຖືກຄົ້ນພົບ.
ການຫັນປ່ຽນວິວັດທະນາການ
Ledumahadi ມີຄວາມກ່ຽວຂ້ອງຢ່າງໃກ້ຊິດກັບໄດໂນເສົາ sauropod ລວມທັງຊະນິດທີ່ມີຊື່ສຽງ Brontosaurus ແລະ Diplodocus. ມັນເປັນສັດກິນຫຍ້າກິນພືດ, ມີແຂນຂາຫນາແລະເປັນ quadruped ເຊັ່ນວ່າມັນຍ່າງທັງສີ່ຂາໃນທ່າທີ່ຄ້າຍຄືກັບຊ້າງທີ່ທັນສະໄຫມ. ເມື່ອປຽບທຽບກັບແຂນຂາຍາວ, ຮຽວຂອງ sauropod, forelimbs ຂອງ Ledumahadi ແມ່ນ crouched ຫຼາຍ, ເຊັ່ນ: ມັນມີປີກ flexed ຫຼາຍຄືໄດໂນເສົາ primitive. ບັນພະບຸລຸດຂອງພວກເຂົາຍ່າງສອງຂາເທົ່ານັ້ນແລະພວກເຂົາຕ້ອງປັບຕົວເພື່ອຍ່າງທັງຫມົດສີ່ແລະນັ້ນແມ່ນເຫດຜົນທີ່ວ່າພວກມັນເຕີບໃຫຍ່ຂຶ້ນເພື່ອສະຫນັບສະຫນູນການຍ່ອຍອາຫານຍ້ອນວ່າພວກມັນເປັນສັດກິນພືດ.
Researchers compared ຟອດຊິວ data from dinosaurs, reptiles etc who walked on two or four legs and they measured limb size and thickness. This is how they concluded Ledumahadi’s posture and its way of walking on all four limbs. It is understood that many other dinosaurs must have experimented walking on all four limbs which could optimally balance a bigger body. Based upon these collective observations, researchers say that Ledumahadi was definitely a ‘transitional’ dinosaur, as it had ‘crouched’ yet very thick limbs to support its large body. Their limb bones– both arms and legs – are very robust and similar in shape to giant sauropod dinosaurs but obviously thicker while sauropods had more slender limbs. The evolution of four-legged postures came before their giant bodies. Just sheer size and elephant-like limb posture helped them, example sauropods, to become one of the most dominant dinosaur groups during the Jurassic era. Ledumahadi definitely represents a transitional stage between two major groups of dinosaurs. The group of early dinosaurs were experimenting with various ways of becoming bigger in size during the first tens of millions of years of their evolution. What it means for research is that the evolutionary transition from a small, bipedal creature to a large, quadrupled sauropod is a complex path and this evolution certainly led to survival and achieving dominance.
The discovery published tells us that even more than 200 million years ago, these dinosaurs were the largest vertebrates to be present on the ດາວ, and this time period was almost 40-50 million years earlier than giant sauropods were first seen. The new dinosaur is closely related to giant dinosaurs who lived in Argentina around that time supporting the idea that all continents that we see today were assembled as Pangea – a supercontinent comprised of world’s land mass during Early Jurassic. And at that time this region of South Africa was not mountainous as we see it today but was flat and semi-arid with shallow streams. Certainly, it was a thriving ecosystem. Like Ledumahadi, many other dinosaurs – both giant and tiny – roamed the place at the time. It is fascinating that South Africa has helped to understand the rise of giant dinosaurs during Jurassic era.
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{ທ່ານສາມາດອ່ານເອກະສານການຄົ້ນຄວ້າຕົ້ນສະບັບໄດ້ໂດຍການຄລິກທີ່ລິ້ງ DOI ທີ່ໃຫ້ໄວ້ຂ້າງລຸ່ມນີ້ໃນລາຍຊື່ແຫຼ່ງທີ່ອ້າງອີງ}
ແຫຼ່ງຂໍ້ມູນ (s)
McPhee BW et al 2018. Giant Dinosaur ຈາກ Jurassic ທຳອິດຂອງອາຟຣິກາໃຕ້ ແລະ ການຫັນປ່ຽນໄປສູ່ Quadrupedality ໃນ Early Sauropodomorphs. ວິທະຍາສາດ. 28(19). https://doi.org/10.1016/j.cub.2018.07.063
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