The discovery of a skeleton called "Lucy" in 1974 sent waves through the scientific community, as she essentially represented a "missing link" between our ape ancestors and modern-day humans. Lucy hails from the species Australopithecus afarensis, natives of Eastern Africa around 3 million years ago.
Lucy walked upright, possessed a face resembling a cross between modern humans and apes, and, like many Australopithecus, displayed other traits familiar to us. Lucy the Hominid told a story through her bones, but she did much more than that. For many people, Lucy started the debate about what it means to be human.
Lucy only stood around 3.5 feet tall and weighed between 60-65 pounds. Although some scientists believe her small size shouldn't lead to assumptions about her gender, others think it points towards her being female. The species Australopithecus afarensis is sexually dimorphic, meaning the males differed in size and appearance from the females.
In most sexually dimorphic ape species, the males possessed larger teeth - but with Australopithecus afarensis, teeth size in both men and women remained the same. Scientists posit the theory that this species didn't require large teeth for displays of male dominance.
To date, only one plausible theory exists for Lucy's death: a considerable amount of circumstantial evidence points to a fall from a great height. Lucy suffered compressive fractures to many areas of her body, and some experts believe she died from these injuries. Australopithecus afarensis transitioned from living in trees to walking upright on the ground, so a fall from a high tree makes sense.
With no evidence of carnivores feeding on her body, a predator likely didn't attack or kill Lucy. Scientists, however, may never determine her cause of death with any certainty.
According to researchers, Lucy's skeleton bears "evidence clearly pointing to bipedality." Her legs hold a few clues, as the knee joints and kneecaps show signs of biped motion. Her pelvis also indicates adaptations for standing upright rather than living on all fours.
Also, her toes look closer to human toes than those of an ape (big toe forward instead of to the side), and her spinal vertebrae possess the curvature needed for standing up straight.