La mécanique de marche humaine a évolué avant le genre Homo [apparu entre 200 000 et 300 000 ans] il y a 3.6 millions d’années.
23 avril 2018
Human-like walking mechanics evolved before the genus Homo: Ancient footprints help researchers date the switch from a crouched to more straight-legged gait.
Le résumé : ▻https://www.sciencedaily.com/releases/2018/04/180423085443.htm
L’article original est paru dans “Experimental Biology 2018”.
Walking upright with the legs fully extended uses less energy than bipedal walking in a more ape-like crouched manner, allowing one to endure longer journeys. This suggests that the switch to a more human-like gait likely had something to do with how our ancestors found food — and how far they had to travel to find it.
The data suggest that by this time in our evolutionary history, selection for reduced energy expenditures during walking was strong," said Raichlen. "This work suggests that, by 3.6 million years ago, climate and habitat changes likely led to the need for ancestral hominins to walk longer distances during their daily foraging bouts. Selection may have acted at this time to improve energy economy during locomotion, generating the human-like mechanics we employ today.
Footprints from (A) a modern human walking normally, (B) a modern human walking with a stooped posture known as the “bent knees, bent hip,” or BKBH, posture, and (C) 3.6 million-year-old hominin footprints found in Laetoli, Tanzania. The team’s analysis suggests ancient hominins probably walked in a way that is very similar to modern humans.
#Préhistoire #mutation #évolution #David_Raichlen #Université_de_l'_Arizona