I live on the basement floor.
What you remember about Lucy is probably wrong. I seem to recall her being the remains of our oldest discovered ancestor, and so she was when discovered in the deserts of northeastern Ethiopia in 1974. But, as I learned in the stellar cellar exhibit of Addis Ababa's National Museum, Lucy is yesterday's news.
About 3.2-million years old, relatively complete (relative is a key word here), with evidence of a bipedal life, a small brain, and a hot bod, Al-288 yielded a dynamo discovery. “Lucy in the Sky with Diamonds” playing on the cassette player, her name was an easy choice for the white folk (though she’s known locally as Dinkenesh, “you are amazing” in Amharic).
But Australopithecus afarensis is a wee lassie when compared with more-recent finds as old as 6 million years. And about 360 of her kind have been found in the region so she's not as unique as she used to be (who is?). Ethiopia competes with Kenya to find our oldest ancestors. Every few years somebody discovers an older great uncle and pushes the bar a few hundred thousand years higher.
I know what you're thinking. "How do they know how old these people are?" They use the same method I use at sleazy nightclubs: the argon-argon radiometric dating method. Hasn't failed me yet. And how do they know Lucy walked upright? Because of her valgus knee. In short, stop asking stupid questions.
What I found most impressive is how much they can tell about our ancestors from so little remains. For example, the photo at top presents the earliest remains that have thus far been discovered. From them, anthropologists have confidently inferred that our ancient grandparents ate meat, enjoyed long walks on the beach, and preferred to have sex on Sundays.