The tiny foot, about the size of a human thumb, is part of a almost complete 3.32-million-year-old skeleton of a young female Australopithecus afarensis discovered in 2002 in the Dikika region of Ethiopia by Zeresenay (Zeray) Alemseged, a professor of organismal biology and anatomy at the University of Chicago and senior author of the study. When she died, she was nearly 3 years old.
"For me the surprise was finding features that are ape-like in an otherwise human-like foot", Alemseged said.
For the first time, scientists have figured out how the toddlers of humanity's earliest ancestors walked and climbed trees to escape from predators. "For the first time, we have an unbelievable window into what walking was like for a two-and-a-half-year-old, more than 3 million years ago". "The Dikika foot adds to the wealth of knowledge on the mosaic nature of hominin skeletal evolution" explained Alemseged.
At just two and a half years of age, this Dikika child was already walking on two legs. The skeleton was initially dubbed "Lucy's baby" because of its close proximity to the adult female A. afarensis fossil named Lucy, found in 1974. "This is the most complete foot of an ancient juvenile ever discovered", stated the study's leading author Jeremy DeSilva from the Dartmouth College.
Scientists started to study one of Selam's foot to find out more about how our ancestors walked.
Concerned England fans make the same joke about the referee against Sweden
Here's how the nation watched and reacted to another England win in Russian Federation . You have to respect you are faced with a good keeper", Andersson said.
Before this discovery, the oldest and most complete fossilized foot was 1.8 million years old and belonged to a Homo habilis, nicknamed OH 8. Since the 2006 analysis, the bones have been exposed and cleared of sediment, revealing more information.
Accordingly, the base of the big toe and the skeletal structure surrounding it suggests that vulnerable children spent more time in the trees than their adult carers.
An important piece in the hominid evolution, Australopithecus afarensis was spending more time walking upright, preferring the ground over the trees and exhibiting some of the traits of the modern human. However, the bone at the base of our big toe-called the medial cuneiform-has a connection for the big toe that is more curved and slightly more angled than what is found in humans today. "We conclude from this, and from previous studies on the shoulders of the Dikika child that she would have been able to climb, and to also grasp onto her mother during travel".
"[Children] were smaller, probably more playful, and also had to scurry up into the trees to get away from predators more frequently than the adults did", DeSilva told Gizmodo. Even with those abilities, she would have been better at walking than climbing. He holds a B.A.in Psychology from the University of Toronto, and a Master of Science in Public Health (M.S.P.H.) from the School of Public Health, Department of Health Administration, at the University of North Carolina at Chapel Hill.