When you purchase through links on our site , we may earn an affiliate committee . Here ’s how it do work .
" Lucy , " our 3.2 million - yr - older hominin relation , could n’t run very tight , according to a new study . But model her track ability has provided new insights into the evolution of human general anatomy key to run performance .
The human power to take the air and operate efficiently on two invertebrate foot move up around 2 million age ago with ourHomo erectusancestors . But our earlier relatives , the australopithecine , were also bipedal around 4 million age ago . give the long arms and different body proportion of metal money likeAustralopithecus afarensis , though , research worker have assumed that australopithecines were less adequate to of walking on two branch than modern human beings .
A virtual model showing Lucy’s speed at 9.5 mph (15.3 km/h). Research showed thatAustralopithecus afarensis’s speed topped out at 11 mph (18 km/h).
In a study bring out online Dec. 18 in the journalCurrent Biology , a squad of researchers mold the gaunt and muscular physical body of Lucy to determine her maximum running speed , the energetic costs associated with running , and her head for the hills endurance .
Through a serial of simulations of fly the coop gait , the researcher wrote in their study that Lucy ’s " maximum run speed was considerably lower than our human model , " topping out around 11 miles per hour ( 18 km / h ) . For reference , Usain Bolt ’s top speedis more than 27 miles per hour ( 43 km / h ) and arecreational runner’stop sprinting f number is about 13.5 mph ( 22 klick / h ) . to boot , in spite of this lower top stop number , Lucy used up between 1.7 and 2.9 times more energy than modern human being do to be given that tight , hint she would have postulate importantly more DOE to journey a given distance than a modern human would .
australopithecine like Lucy had large upper bodies , long weaponry and light legs , which likely limited their track pep pill . But the researchers discovered that another potential cause for Lucy ’s dumb , inefficient track may have been a differently shapedAchilles tendonand triceps surae , a chemical group of muscles in the calf .
relate : Lucy ’s last daylight : What the iconic fossil reveals about our ancient ascendant ’s last hours
Modern humans have a long , outpouring - like Achilles tendon , the researchers noted , which connects calf and articulatio talocruralis sinew to the heel osseous tissue . This anatomic arrangement furnish man with the powerful and efficient mortise joint all-important to high running performance .
When the researchers modeled Lucy ’s movement with man - similar Achilles and calf muscles , she was still slower , but the differences in this tweaked running ability were mostly due to her small-scale consistency size .
— From ' Lucy ' to the ' Hobbits ' : The most noted fogey of human relatives
— Ancient human ascendant Lucy was not alone — she live alongside at least 4 other proto - human species , emerging inquiry suggests
— Our antecedent Lucy may have used puppet more than 3 million years ago
" This wider context therefore emphasizes the important purpose of the Achilles tendon and triceps surae architecture in the evolution of hominin move energetics , " the researcher write in the sketch . " primal feature in the human organic structure plan evolved specifically for improved pass performance . "
The new study is the first time researcher have directly judge carry ability in Lucy ’s species using musculoskeletal modeling , the investigator mark , but further study is needed , such as models that include arm swing and torso rotations to more fully understand the difference between australopithecine and human locomotion .
