Name: When Hobbits Were Real
Uploaded: 2021-05-04T02:36:18.000Z
Duration: 10 min 28 s
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基礎受動態

In October 2004, our understanding of the human family tree was turned upside down.

過去完了形

That's when anthropologists reported that they'd discovered the bones of a tiny, unknown

hominin, on the Indonesian island of Flores.

This little creature stood only about a meter tall and had a brain about the size of a chimpanzee's.

We already knew about small-bodied, small-brained hominins in the human fossil record, like

What was really striking about this skeleton is that, at first at least, it appeared not

to have been very old, and yet it had features of much older, more basal hominins.

The original description of the bones dated them to between about 35,000 and 14,000 years

ago, which means that they would have lived at the same time as us.

But the last time a hominin with a brain that small was around, was millions of years ago

- not thousands - well before modern Homo sapiens was on the scene.

And the rest of its skeleton was equally baffling.

Its shoulder joint wasn't like that of any modern human.

It had short collarbones, which meant that the shoulders were rotated forward in a way

that hadn't been seen since early specimens of Homo erectus, from around 1.6 million years

The three bones of its wrist that were found were also strangely archaic-looking.

They were shaped like the bones of African apes and australopithecines - not like ours.

And its feet were really long compared to the length of its legs.

We're talking ape-like, not human-like, proportions.

And yet, it had short big toes and was probably an effective bipedal walker.

Its discoverers named this puzzling hominin Homo floresiensis, but it's often called

“the hobbit” for its short stature and oddly proportioned feet.

And it's been at the center of a major controversy in the field ever since.

It's been fifteen years now since its discovery was first announced, and we're still exploring

what this little hobbit can tell us about the shape of the human family tree, and what

it means for our own evolutionary history.

And the questions that this little creature raises are big:

Or, could it even have descended from a whole lineage of hominins that we don't even know

The partial skeleton that started the whole controversy is called LB1.

And it belonged to an adult female Homo floresiensis, based on the shape of her pelvis and the fact

But she's not the only hobbit that anthropologists have found.

Since her discovery, the remains of as many as 11 other members of her species have been

recovered, although LB1 is still the only one with a skull.

And all of these hobbits come from a single site: a limestone cave called Liang Bua, located

in the western part of the island of Flores.

So, when LB1 was discovered in 2003, one of the first things scientists had to figure

out was how to explain her tiny size and strange mix of features.

What branch of our family tree could've produced such an odd hominin - a hominin,

by the way, being a primate that's more closely related to us than to chimps?

The team suggested that her species had evolved from a population of Homo erectus that became

And then, thanks to evolutionary pressures, their bodies got smaller over time.

Now, there are fossils of Homo erectus from other Indonesian islands, and they cover a

wide range of time -- from 1.6 million to just 143,000 years ago.

So we know that Homo erectus made it to that part of the world.

And we know that mammals on islands can change dramatically in body size over time, thanks

to a phenomenon known as Foster's rule, which we've talked about before.

This rule says that big mammals on islands often get smaller, and small mammals tend

to get bigger, as they adapt to limited resources and fewer predators.

So in the original paper about the hobbit's discovery, the researchers proposed that a

group of Homo erectus somehow got stuck on Flores, and they eventually evolved into a

new species: the smaller Homo floresiensis.

And, Flores wouldn't have been a terrible place to be stranded.

Today, it's a forested tropical island, and it seems to have been pretty similar,

if more variable, while Homo floresiensis was around.

Now, it's not clear whether the hobbits actually lived in the cave where their remains

But, based on the number of animal bones and stone tools found in different layers of the

site, they seem to have used the cave more when the environment was wetter, and less

And the hobbits seem to have had a rather … exotic diet, at least by our standards.

The animal remains found in the cave include a lot of very young pygmy Stegodon, an elephant

relative that, like the hobbits, seems to have evolved into a smaller version of its

A number of these bones have cut-marks on them, and some are even burned, so Homo floresiensis

And there were also lots of bones of Komodo dragons, which are still formidable predators

It's not clear whether the hobbits were hunting the Komodo dragons or just scavenging

them - but it's possible that the hobbits might have been hunted by the dragons!

Interestingly enough, there don't seem to be any bones of adult pygmy Stegodon in the

cave, which suggests that the hobbits might not have been able to take down a full-grown

The hobbits also left behind a number of simple stone tools, like cores, flakes, and points,

some of which seem to have been used not only for hunting, but also for processing plant

But other experts weren't convinced that these artifacts had been made by a new species

Instead, they thought the so-called hobbits were actually modern Homo sapiens, but from

a population of very small-bodied people, like some groups of tropical hunter-gatherers

And, they argued, LB1 likely had some kind of pathological condition.

To support their case, these researchers compared the bones from LB1 with the skeletons of various

indigenous peoples of Indonesia and Australia.

Their thinking was that the best populations to compare them to would be ones that lived

in the same region and environments as the hobbit.

And, they said, more than 140 features of LB1's skull matched those of modern humans

But the researchers who thought Homo floresiensis was a new species countered this argument.

They said that there are a number of groups of people from around the world who have adapted

to their environments by becoming smaller - but none of them ended up with the same

tiny brain and odd limb proportions as the hobbit.

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When Hobbits Were Real

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