Welcome to 2024! Let's learn about some exciting new discoveries in our own family tree! Further reading: 476,000-Year-Old Wooden Structure Unearthed in Zambia Mysterious 300,000-year-old skull could be new species of human, researchers say Show transcript: Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. It’s time to start the new year off with an episode that has me really excited. I was initially going to include this in the updates episode that usually comes out around summertime, but I just can’t wait. In 2023, scientists discovered what they think might be a new lineage of extinct human ancestors! We’ll come back to that in a moment, but first I want to highlight another amazing human-relateded discovery from 2023. And just to let you know, I am going to be using the words "humans" and "people" and "hominins" more or less interchangeably. I try to make it clear when I'm talking about Homo sapiens versus other species of ancient hominin, but these are all our ancestors--in many cases our direct ancestors--so they're all people as far as I'm concerned. As you may know, especially if you’ve listened to previous episodes where we’ve discussed ancient human ancestors, the ancestors of all humans evolved in Africa. Specifically, we arose in the southern part of Africa, in areas that had once been dense forest but gradually changed to open woodland and savanna. Because there weren’t very many trees, our far-distant hominin ancestors, the australopiths, no longer needed to be able to climb trees as well as their ape cousins. Instead, they evolved an upright stance and long legs to see over tall grasses, and the stamina to run after the animals they hunted until the animal was exhausted and couldn’t run anymore. Once our ancestors were walking on two legs all the time, their hands were free to carry babies and food and anything else they wanted. Being fully bipedal meant that women had a harder time giving birth, since the pelvis had to change position to allow them to walk and run, so babies started being born when they were smaller. This meant the babies needed a whole lot more care for a lot longer, which meant that family groups became even more important and complicated. One thing we’ve learned about sociability in animals is that it leads to increased intelligence, and that’s definitely what happened with our long-distant ancestors. As their brains got bigger, they became more creative. They made lots of different types of tools, especially weapons and items that helped them process food, but eventually they also made artwork, baskets, clothing, jewelry, and everything else they needed. All this took a long time, naturally. We know Australopithecus used stone tools over three million years ago, but we don’t have evidence of human ancestors using fire until a little over 1.5 million years ago. Homo sapiens was once thought to have only evolved around 100,000 years ago, maybe less, but as scientists find more remains and are able to use more sophisticated techniques to study those remains, the date keeps getting pushed back. Currently we’re pretty certain that actual humans, if not the fully modern humans alive today, arose about 300,000 years ago and maybe even earlier. Homo sapiens evolved from Homo erectus, which arose about two million years ago and went extinct about 100,000 years ago. They were probably the first hominin to use fire, which allowed humans to start migrating longer distances into colder climates. They might also have communicated with language. Basically, Homo erectus was a lot like us but not quite us yet. The modern-day country of Zambia is in the middle of south-central Africa, and naturally it’s been home to humans and our ancestors for as long as humans have existed. One especially important part of Zambia is also one of its most beautiful places, Kalambo Falls, which is really close to the equally important and beautiful country of Tanzania.