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Strange Animals Podcast

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Welcome to Strange Animals

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Podcast. I'm your host,

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Kate Shaw. It's time

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to start the new year off with

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an episode that has me really excited.

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I was initially going to include this

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in the updates episode that usually comes

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out around summer time, but I just

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can't wait. In

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2023, scientists discovered what they

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think might be a new

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lineage of extinct human ancestors.

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We'll come back to that

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in a moment, but first

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I want to highlight another

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amazing human-related discovery from 2023.

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And just to let you know,

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I am going to be using

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the words humans and people and

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hominins more or less interchangeably. I

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try to make it clear what

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I'm talking about. Homo sapiens versus

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other species of ancient hominin. But

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these were all our ancestors. In

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many cases, our direct ancestors. So

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they're all people as far as

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I'm concerned. As you

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may know, especially if you've listened

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to previous episodes where we've discussed

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ancient human ancestors, the ancestors of

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all humans evolved in Africa. Specifically,

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we arose in the southern part

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of Africa in areas that had

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once been dense forest, but gradually

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changed to open woodland and savannah.

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Because there weren't very many trees,

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our far distant hominin ancestors, the

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Australopiths, no longer needed to be

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able to climb trees as well

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as their ape cousins. Instead,

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they evolved an upright stance and

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long legs to see over tall

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grasses, and the stamina to run

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after the animals they hunted until

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the animal was exhausted and couldn't

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run anymore. Once our ancestors

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were walking on two legs all the

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time, their hands were free to carry

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babies and food and anything else they

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wanted. Being fully bipedal meant

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that women had a harder time giving

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birth, since the pelvis had to change

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position to allow them to walk and

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run, so babies started being born when

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they were smaller. This meant

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the babies needed a whole lot more

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care for a lot longer, which meant

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that family groups became even more important

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and complicated. One thing

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we've learned about sociability in

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animals is that it leads

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to increased intelligence, and that's

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definitely what happened with our

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long-distance ancestors. As their

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brains got bigger, they became

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more creative. They made lots

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of different types of tools,

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especially weapons and items that

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helped them process food, but

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eventually they also made artwork,

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baskets, clothing, jewelry, and everything

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else they needed, until the

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present day when we're all

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making podcasts. All

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this took a long time, naturally.

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We know Australopithecus used stone tools

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over 3 million years ago, but

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we don't have evidence of human

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ancestors using fire until a little

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over 1.5 million years ago. Homo

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sapiens was once thought to have only evolved

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around 100,000 years ago, maybe less, but

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as scientists find more remains and

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are able to use more sophisticated

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techniques to study those remains, the

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date keeps getting pushed back. Currently,

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we're pretty certain that actual humans, if

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not the fully modern humans alive today,

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arose about 300,000 years ago, and maybe

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even earlier. Homo

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sapiens evolved from Homo erectus, which

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arose about 2 million years ago

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and went extinct about 100,000 years

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ago. They

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were probably the first hominin

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to use fire, which allowed

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humans to start migrating longer

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distances into colder climates. They

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might also have communicated with

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language. Basically, Homo erectus

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was a lot like us, but not quite

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a series of things. The

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modern-day country of Zambia is in

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the middle of south-central Africa, and

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naturally it's been home to humans

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and our ancestors for as long

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as humans have existed. One

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especially important part of Zambia is

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also one of its most beautiful

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places – Colombo Falls, which is

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really close to the equally important

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and beautiful country of Tanzania. Scientists

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have known that humans of one kind or

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another have lived around Colombo Falls for at

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least 447,000 years, long before Homo sapiens actually

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evolved. When

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a team of archaeologists excavated a sandbar

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near the falls in 2019, they were

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surprised to find wooden artifacts.

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Wood doesn't usually preserve for very

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long, and the site they were

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excavating was quite old. In

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addition to wooden tools, they found two

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logs that had been shaped and notched

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to allow them to fit together securely.

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The researchers thought the logs had once

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been part of a structure like a

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walkway that would keep people's feet out

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of the mud and water, or possibly

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the floor of a wooden structure used

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to store food. It might even

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have been the floor of a little house. Wood

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can be dated with simple tests to find

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out its age, but the test is only

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useful for trees that died within the last

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50,000 years. Anything

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older than that is just, you know, older

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than 50,000 years. The

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tools and logs tested as older,

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which the scientists expected. Fortunately, there

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are other ways to date older

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wood, but the results of those

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tests were surprising even to the

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scientists. The tools were at least 324,000

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years old, possibly as much as 390,000 years old, but

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the logs were even older, about 476,000

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years old. Remember,

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Homo sapiens didn't even evolve until

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about 300,000 years ago. That

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means human life. Humans didn't make those

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tools or build anything with those shaped

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logs. Some other hominin

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did, although we're not sure who.

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Even more exciting, close examination of

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the logs suggests that they may

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have been subjected to fire at

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some point. That might

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mean a natural fire, or it might

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mean that the people who were building

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with the logs were also using fire,

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as much as two million years before

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we thought people were using fire. Obviously,

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scientists are going to look carefully for

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more clues about who might have shaped

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these logs and when. Hopefully

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we'll learn more soon. Around

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the same time that scientists uncovered

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the wooden items in southern Africa,

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another discovery was made in 2019,

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this one in East China. A

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team found a jaw, skull, and

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leg bones of a hominin that

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didn't match up to any known

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human ancestor. The bones

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were dated to 300,000 years ago,

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at the dawn of Homo sapiens.

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Other hominins had migrated to

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eastern Asia long before this,

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however, including populations of Homo

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erectus. The newly discovered

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bones don't belong to Homo erectus,

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though. They don't belong to

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Homo sapiens either, or any other

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known hominin. They represent a

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completely new hominin, and at the

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moment, scientists don't know where exactly

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they fit in our own family

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tree. The bones show

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traits found in modern humans, like

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a flat face, but lack other

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uniquely human traits, most notably a

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chin. Homo sapiens have

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chins, unlike every other hominin, and

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no one's sure why. It

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might have something to do with speech,

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or maybe early humans with chins were

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just considered more attractive, and now everyone

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has a chin. The

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mystery hominin is still being

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studied, but preliminary findings indicate

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that we might have discovered

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the ancestor of a very

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close relation. The bones

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show some traits also found

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in Neanderthals, our very closest

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evolutionary cousins, even though they're

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extinct. There's a possibility that

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this new hominin gave rise to

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another line of very close human

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relations, one we don't have any fossils

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of yet. I know there

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are a lot of excited scientists wanting

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to learn more about the hominin bones.

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Hopefully more bones will turn up soon

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so we can get a better idea

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of who this distant relative is. It's

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a little too early to throw them a

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welcome home party, but maybe we can start

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planning it now. You

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can find Strange Animals

8:42

Podcast at strangeanimalspodcast.blueberry.net. That's

8:45

Blueberry without any ease. If

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you have questions, comments,

8:50

or suggestions for future

8:52

episodes, email us at

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[email protected]. We also have

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a Patreon at patreon.com/strangeanimalspodcast if

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you'd like to support us

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for as little as one

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dollar a month and get

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monthly bonus episodes. Thanks

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for listening! Which

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is really close to the equally

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important and beautiful country of Tanzania.

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It's not Tanzania. I get

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Tasmania and Tanzania mixed up because they

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look very similar like the words, but

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they are very very different.