Previous: 6 Dangerous Diseases Hiding in U.S. Backyards
Next: Can Cold Showers Actually Change Your Life?



View count:136,078
Last sync:2022-11-27 10:45
Right now, you can sign up for 2 months of free unlimited access to Skillshare:

Check out Matt Bellassai’s Skillshare class “Creating for the Viral Internet.”:

Luzia, the oldest human fossil in the Western hemisphere, was lost to the Brazil National Museum fire, but around same time, three new species of ancient primates were discovered in San Diego Natural History Museum.

Hosted by: Hank Green

Head to for hand selected artifacts of the universe!
Support SciShow by becoming a patron on Patreon:
Dooblydoo thanks go to the following Patreon supporters: Lazarus G, Sam Lutfi, D.A. Noe, سلطان الخليفي, Piya Shedden, KatieMarie Magnone, Scott Satovsky Jr, Charles Southerland, Patrick D. Ashmore, Tim Curwick, charles george, Kevin Bealer, Chris Peters
Looking for SciShow elsewhere on the internet?
Sources: [PDF]®ion=rank&module=package&version=highlights&contentPlacement=2&pgtype=sectionfront

Image Sources:
Thanks to Skillshare for supporting this episode of SciShow. [ ♪ INTRO ].

Luzia was pretty much like every other 20 year old of her generation. She was fairly short — around 152 centimeters tall — and liked hanging out with her friends and snacking on fruit and nuts.

All of which might seem pretty boring, except that Luzia died over 11,000 years ago. Her remains — which include her skull, pelvis, an arm bone, and a couple of leg bones — are the oldest human fossil in the Western hemisphere. And about two weeks ago, they burned alongside some 20 million items in the Brazil National.

Museum when the main buildings caught fire. The museum had stood for 200 years before the blaze brought it to the ground on September 2. The fire started in the evening, after the museum was closed, and thankfully, none of the museum staff were harmed.

But the fire didn’t spare countless priceless and irreplaceable artifacts. Until authorities sort through the ash, we won’t know exactly what is gone and what can be salvaged. But it’s likely that Luzia’s remains are among the treasures destroyed by the flames — which is not only a loss for the museum and the country of Brazil but also for science.

Radiocarbon estimates of charcoal found near her bones estimate that she’s roughly between 11,200 - 11,700 years old. That makes her about 2000 years older than any other human fossils from the Americas. And it’s not just her age that makes her special.

It’s also her face. You see, her oval cranium, pronounced chin and projecting face kind of put a damper on the main theory of how the Americas were first populated. When Luzia was discovered in 1975, paleontologists thought our species arrived in the Americas via a single movement of people from Northern Asia.

That’s because the fossil skulls they had at the time all had facial features that were similar to North Asian faces. But Luzia’s skull looks more like the skulls of people living in Africa. And because of that, along with other bits of evidence that have arisen since, paleontologists now think the Americas were populated in waves.

For all that Luzia taught scientists, though, she had so many more secrets she could have revealed. Paleontologists were especially eager to look at Luzia’s genes but the methods for extracting. DNA weren't advanced enough yet for such an old fossil.

And the museum was hoping to preserve the skeleton until those advancement happen. Even if parts of her are recovered from the ash, the heat from the blaze likely destroyed what little DNA may have remained. And Luzia is one of just millions of specimens that burned.

Much of the anthropological collection is likely gone, including stunning cultural artifacts from around the world and the only recordings of indigenous languages no longer spoken. Species of delicate lace bugs found nowhere else were incinerated, alongside much of the entomology collection. And many of the destroyed are what scientists call holotypes — the specimens that define species.

These heartbreaking losses show just how fragile museum collections are. ☆It’s all too easy to lose these institutions that let us travel back in time, and that protect specimens until technology or our understanding advances far enough to learn more from them — which is exactly what happened with our next discovery. In a new paper in the Journal of Human Evolution, a team of two scientists describe three new species of ancient primates using fossils that sat pretty much untouched for decades in the San Diego Natural History Museum. The fossils — which are teeth and jaw fragments — came from the Friars Formation, an area with layers of sandstone, siltstone, and mudstone in Southern California.

Scientists compared the teeth with epoxy resin casts of teeth from other fossil primates under a microscope. And based on their structure, they concluded they came from new species of omomyids, ancient primates that gave rise to modern day haplorhines like tarsiers. They think these three species lived between 46 to 42 million years ago, which falls in the middle of the Eocene epoch.

The smallest probably weighed between 120 and 130 grams, and was distinguished by tooth features like its smooth enamel and that it lacks a ridge of enamel on its first molar. The mid-sized species likely weighed between 290 and 350 grams. Its lower molars were less wavy in texture and had longer trigonids — the parts that grinds food.

The low body weight and shearing cusps of the small and medium species suggest they ate a lot of insects, much like many smaller primates do now. Insects provide a lot of protein in a small package. And that’s different than the likely diet of the heaviest new species, which weighed around 750 to 1000 grams.

These heftier little primates had premolars that were fairly narrow with small cusps, suggesting they ate mostly fruit and leaves. As if discovering new species isn’t exciting enough, this finding upends the idea that the middle Eocene was a time when primate species were dying out. While the number of primate species were declining in some areas, it seems that primate communities were growing in places like Southern California.

And these new omomyids haven’t been found anywhere outside of Southern California yet, indicating that maybe this region had its own unique community of mammals at the time. There’s a lot more to learn from these fossil teeth, as well as the millions of unexamined fossils and other specimens that await study in the back rooms of museums around the world. So findings like these further underscore value of natural history collections and the treasures they hold — a sobering but important reminder in the wake of the tragic losses in Brazil.

All this week, we’re taking a moment each day to point you to a class on Skillshare we think is fun and valuable. In the fast pace of the internet, it can sometimes be hard to find content that feels authentic. At SciShow, it’s important to us to make videos we think are going to help people appreciate the world and look at it in a slightly new way.

Which is why we liked Matt Bellassai’s take on “Creating for the Viral Internet.” Matt’s a writer and comedian and he’s really good at making shareable content. But he’s not pandering to the lowest common denominator. In his new class on Skillshare, he teaches how to develop your own voice and make content that’s genuine to who you are and who you want to connect with.

Check it out for free, along with any of Skillshare’s 20,000 other classes by following the link in the description. Right now, you can sign up for 2 months of free unlimited access to Skillshare. Let us know what classes you take.

And thanks for supporting SciShow and all the content that feels important to you. [♪ OUTRO ].