Scientists have excavated the largest dinosaur mafuta which would have been the largest terrestrial animal on our sayari.
Timu ya wanasayansi kutoka Africa Kusini, Uingereza na Brazil wakiongozwa na Chuo Kikuu cha Witwatersrand wamegundua a mafuta ya aina mpya ya dinosaur nchini Afrika Kusini inayodhaniwa kuwa inahusiana na brontosaurus. Dinosau huyu wa mapema wa Jurassic alikuwa na uzito wa pauni 26,000 yaani ukubwa mara mbili ya tembo wa Kiafrika, na anasimama mita nne kwenye kiuno. Imepewa jina la 'Ledumahadi mafube' ikimaanisha 'ngurumo kubwa wakati wa alfajiri' katika lugha ya asili ya Sesotho ya eneo lilikogunduliwa.
Mpito wa mageuzi
Ledumahadi inahusiana kwa karibu na dinosaur sauropod ikiwa ni pamoja na spishi zinazojulikana za Brontosaurus na Diplodocus. Alikuwa ni mla mimea, alikuwa na viungo vinene na alikuwa na miguu minne yaani alitembea kwa miguu yote minne kwa mkao sawa na tembo wa kisasa. Ikilinganishwa na miguu mirefu na nyembamba ya sauropod, miguu ya mbele ya Ledumahadi ilikuwa imeinama zaidi, yaani, ilikuwa na miguu iliyopinda kama dinosaur wa zamani. Babu zao walitembea kwa miguu miwili tu na lazima walizoea kutembea kwa miguu yote minne na ndio maana walikua wakubwa kusaidia mmeng'enyo wa chakula kwani walikuwa walaji wa mimea.
Watafiti walilinganisha mafuta 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 sayari, 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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{Unaweza kusoma karatasi asili ya utafiti kwa kubofya kiungo cha DOI kilichotolewa hapa chini katika orodha ya (vyanzo) vilivyotajwa}
Chanzo (s)
McPhee BW et al 2018. Dinosaur Kubwa kutoka Jurassic ya Mapema Zaidi ya Afrika Kusini na Mpito hadi Upeo Unne katika Sauropodomorphs za Mapema. Bilim. 28 (19). https://doi.org/10.1016/j.cub.2018.07.063
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