Ancient teeth reveal secrets of human cousins

Have you ever wondered how scientists figure out what our ancient human relatives were like? It turns out, the answer might be hiding in something as small as a tooth! Thanks to new research, we are now learning amazing facts about a distant human cousin, Paranthropus robustus, who lived in southern Africa around 2 million years ago. This discovery is a big step forward for health AI and science, as it uses some of the latest technology to unlock secrets from the past.

What are ancient proteins and why do they matter?

When scientists study ancient bones and teeth, they usually try to find DNA. But DNA breaks down quickly, especially in hot places like Africa. That is where proteins come in. Proteins survive much longer than DNA. In a recent study, researchers looked at special protein sequences preserved in four fossil teeth of Paranthropus robustus, giving us a new way to learn about these ancient creatures (see the original research here).

Finding out if fossils belonged to males or females

Scientists have always tried to guess if a fossil belonged to a male or a female by looking at the size of the bones or teeth. Bigger usually meant male, smaller meant female. But, according to this new research, that is not always true! By searching for a protein made only on the Y chromosome (which only males have), researchers could actually tell which fossils belonged to males and which to females. They were surprised to find that some small teeth, once thought to be from females, actually belonged to males. This changes how we understand ancient populations and shows us why using proteins is much more accurate than just looking at size (original study).

Genetic differences in ancient families

But the discoveries did not stop there. When scientists looked closer at other protein sequences, they found that the ancient Paranthropus robustus group was not all the same. Some teeth had slightly different protein versions, hinting that there were different groups or even families living together. One tooth even had a mix of both protein types, showing there was more variety than anyone realized. This suggests that these ancient creatures might have lived in different groups and sometimes mixed together, just like people do today. For more on how ancient populations can be diverse, you can read about deep population structures in Africa (Nature study).

Comparing ancient species with new technology

This kind of protein analysis is called "palaeoproteomics." It is a big deal because it helps scientists compare different ancient species, even when DNA is too old or gone. Researchers have already started using this method on other ancient species, like Australopithecus africanus, to find out more about their lives (South African Journal of Science study). These studies are helping us understand which species are related and how ancient groups changed over time. If scientists can collect enough data from fossils in different places, they might be able to settle some big debates about our evolutionary family tree (Journal of Human Evolution study).

What it means for patients and the future of health AI

You might be wondering why learning about ancient teeth is important for us today. The answer is that the tools and techniques developed for these studies are helping us build better health AI, which can one day be used to study our own health and even fight diseases. For example, similar methods are already being used to make cancer-fighting T cells more effective (see how scientists are making cancer-fighting T cells easier), and to build giant maps of how our body’s cells work together (how our body's cells work together and change in cancer)—all using health AI.

The big picture: learning from the past

Every new discovery about our ancient relatives like Paranthropus robustus helps us understand not just where we came from, but also how our bodies and health have changed over time. By learning about their genetic differences, family structures, and even their diets, we get clues about why we look and act the way we do today. And thanks to new tools like palaeoproteomics and health AI, the next big discovery might be right around the corner.