Final answer:
The Laetoli Footprints are fossilized tracks found in East Africa, which provide key evidence that Australopithecus afarensis walked on two feet with a striding gait over 3.5 million years ago.
Step-by-step explanation:
The Laetoli Footprints represent one of the most significant archaeological discoveries in the study of human evolution. Unearthed by Mary Leakey in the 1980s, these footprints were found in a layer of volcanic ash in East Africa, specifically at the site of Laetoli. They provide crucial evidence that Australopithecus afarensis, an early hominin species, walked upright using a modern striding gait over 3.5 million years ago (MYA). These footprints are about 75 feet in length and were made by three bipedal individuals. Such insights have been pivotal in understanding the evolutionary changes that have occurred in human ancestry, particularly concerning bipedal locomotion. Comparative studies with more recent "ghost tracks" found in locations like White Sands National Park complement the findings at Laetoli by showing the prolonged history of human footprints over time. Homo naledi, another early hominin species, further illustrates the mixture of ancestral and modern traits leading up to contemporary humans. Historic artistic depictions left by early humans, such as handprints and sculptures, add to the narrative of early human culture and craftsmanship, underscoring the importance of these physical traces left behind by our ancestors.