Oh, hi there! Squeaks and I were just checking our e-mail,
and it looks like you have a message from your sister.
Hm, I wonder what it is...Oooh, it's your family tree!
There are his grandparents, and that's his parents in the middle,
and then their kids, including Squeaks and his sister!
Your family is pretty great! I have my own family tree, too.
Everybody does, and it can be arranged in all kinds of different ways
depending on the people that make up your family.
And people, all people, make up one branch on a really big, complicated family tree.
We're related to all the other animals on earth.
And each type of animal or species, has its own special scientific name.
Our species is called "Homo sapiens", which just means "wise people."
Human beings, all 7 billion people on earth, are all members of Homo sapiens.
And we Homo sapiens have a lot of relatives!
Of the animals that are alive today,
we're most closely related to the great apes, like chimpanzees and bonobos,
but our families went their separate ways millions of years ago.
These days, we're the only living species that's considered human.
But we weren't always the only species of humans.
There were others, like the Neanderthals!
See, over thousands or millions of years,
the earth's weather changes a lot, from hot to cold and back again.
Sometimes food is easy to find,
but sometimes animals and people need special talents and tricks to find food and survive.
If a new species came along while the earth was going through a change,
and if it had some special talents to help it survive,
that species might last through a really cold or really warm period, while some other species wouldn't.
And that's what happened to the other types of humans,
when things changed, they weren't able to survive.
Some of them were our ancestors, meaning that we come from them.
Other species are more like our distant cousins,
but a lot of them died out before any Homo sapiens ever got to meet them. Some didn't, though!
A few other species of humans lived on earth at the same time as early Homo sapiens,
including the Neanderthals.
Neanderthals weren't people in the exact same way Homo sapiens are,
but they acted a lot like the humans we know!
They lived in families and took care of each other when they got sick;
they used fire; they wore clothes; and they had big brains.
And we know they existed because we have the fossil record.
Fossils are any preserved remains we find of species that used to be alive.
Like dinosaur bones! Or the remains of a meal, or footprints.
Scientists have found thousands of fossils of our early human relatives from other species.
And we sometimes find evidence of things those early humans made, like tools and art.
Some species have only left us a few clues.
But even just from a fossil or two, we can make a pretty good guess about a species:
whether they walked upright like us, what they ate, how big they grew up to be,
and whether their species would have survived better in a hot or cold climate.
The Neanderthals had smaller bodies that looked a lot like Homo sapiens, but were better for the cold.
They had big noses that could heat up the cold air they breathed.
And their bodies were stronger and broader than ours, with wider shoulders and hips, and shorter arms and legs.
That kept them from losing too much heat,
which was perfect for surviving the freezing cold weather during the time they lived.
They also invented tools that helped them become super talented at hunting the enormous animals that were around back then.
But then things changed a lot, and the Neanderthals weren't able to adjust.
When the types of animals they ate started to die out, or go extinct, there was less food for the Neanderthals.
And when Homo sapiens spread out across Europe, where Neanderthals lived,
it's possible that Neanderthals couldn't compete with them for food and shelter.
Neanderthals went extinct about 40,000 years ago.
So we don't have any living Neanderthals around today, but we still have their fossils,
along with some of the tools they made, to help us learn about how they lived.
Relationships with family sure are complicated!
If Homo sapiens are the only human species we've got,
I guess we need to make sure we're really good at getting along!
Thanks for joining us!
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and we'll see you next time, here at the Fort!