How Did Our Most Famous Ancestor Really Die?

Did our most famous fossil ancestor, Lucy, die by falling out of a tall tree? The answer is part of a decades-long debate over how, exactly, our ancestors transitioned from life in the trees to life on the ground.

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[eons]

Hey Eons fans! We wanted to clarify something in this video that’s pretty important to the process of science: peer-review. The 2016 study about the damage on Lucy’s bones went through the process of peer-review before it was published in a scientific journal, which means that experts in the field were given the opportunity to evaluate everything from its introduction to its methods, data, and conclusions before it was accepted for publication. Toward the end of the video, we quoted some other paleoanthropologists who disagreed with the authors of the 2016 study and spoke about their disagreements to the press. We want to make sure to clarify that remarks to the press shouldn’t be given the same weight as peer-reviewed scientific literature.

[seattlegrrlie]

As a child I was a tree dweller. Trees, bridges, houses, playground toys, fences... you name it, I climbed it and sat on top of it. Lucy doesn't need to be full tree dwelling species to fall out of a tree

[DivinePonies]

When he mentioned how Lucy was 1m tall, it reminded me of how small the skulls of our ancestors were when I saw them all side by side in a museum. It is such bizarre thing to see up close - a skull of a grown human that can easily fit on the palm of a hand. Imagine them side by side with some of the larger animals of that time. Or rather, imagine encountering a human species like that today, somewhere in the wilderness. It would probably feel like encountering extraterrestrial.

[xooberant]

A few of our fellow humans still demonstrate truly amazing skills for climbing trees, cliffs and other things.

[tarjei]

Since these lived on the savanna, trees would be emergency exits for our ancestors. I would expect that the upper body would reflect that this was useful for a long time.

[matthewtaylor]

I just shattered my left proximal humeral head, and broke the shaft as well. Odd timing with this video. I feel bad for Lucy. It's agony. She must've suffered a lot.

[SadisticSenpai]

One of the authors of that paper came to my university in 2017 and gave a couple talks. Basically, he did scaled up the size of Lucy's arm to match human proportions, did a 3D print of it, and took it to sports doctors and surgeons to see what they thought the cause of the fracture was. They all said it was a fall from height. And then one of the surgeons added that he thinks he could fix it. lol

I think it's extremely likely that A afarensis likely still climbed trees regularly - whether to reach fruit, escape from predators, or sleep for the night. And given most of their predators in the savanna likely didn't climb trees all that well, sleeping in trees was probably the safest place to kip down for the night - esp if they didn't have fire (and there's no indication that A afarensis used fire).

It's very reasonable to think that until the adoption and widespread use of fire, our ancestors likely still retreated to the trees at night if they were available.

[boilingwateronthestove]

Even today, people especially kids love or like the idea of climbing in trees. So i wouldn't be surprised if people of Lucy's time despite already being upright walkers would chill in the trees still from time to time.

[sophierobinson]

I wish I had income enough to become a patron and have it be listed “In Memory of Steve”, a man I never knew, but miss.

[TheUltimateBlaziken]

Perhaps Lucy, assuming her species did climb trees, did so to get some fruit; or maybe to try and escape a predator and slipped or potentially even got thrown off

[stanley]

I used to talk about (a replica of) Lucy when I was a museum tour guide, I always like learning more about her

[Lilpumpkin]

I haven't finished this video yet, but even know one thing that connects children all over the world is their love for climbing. I could definitely see that children were taught to stay in the trees while parents did work on the ground in order to keep them safe

[thedarkside]

Can we be ABSOLUTELY SURE that rhinos didn't fall out of trees back then?

Great episode, I love your summary on this topic. Wish we had a time machine!

[TheDarkLasombra]

Interesting that the scientists couldn't tell the damage happened after fossilization. I would have thought there were big differences between a fresh bone break and a rock breaking.

[fernplant]

I recently saw Lucy at the Cleveland Museum of Natural History and it was incredible to see the remains of every humans’ ancestor. I highly recommend visiting the museum if you are able to

[nikkicat]

The fact that WE as humans sometimes climb trees NOW, tells me that Lucy, her kind and beyond climbed trees too, sometimes to get away from predators, but also maybe to just see the path ahead of them! But also they may have still slept in trees, since it would be safer then sleeping on the ground!

I mean a lot of humans of today do these same things, so before it was brought up that other animals had some of the same breaks in her aria, I just imagined she had climbed up into a tree to get away from something trying to eat her and maybe she was so scared she slipped and fell out! It's not out of the realm of possibilities, so she could have died that way, still!

[Merennulli]

I was compelled to give a Phillip J. Fry "I get it!" on the "we still love Lucy" line. They really like giving you the wordplay lines.

[ThiagoZwetsch]

The way that you guys present this show is awesome. Congratilations for all the team!

[Beryllahawk]

A very interesting hypothesis, it's really too bad that behaviors don't fossilize. So inconvenient, haha!
And I still love how Blake can't help but giggle about the silly word-play at the end of each video. It's great.

[mellow-jello]

Nostalgia tour with Hank and Steve narrating Eons, great Xmas gift to.viewers, thank you both.