Ancient DNA Reveals A Girl With Parents of Two Different Species

Here is one such example. What began as a chance encounter soon became an important finding. The story made its way through various research papers, and eventually, all the way to National Geographic. To this day, this amazing research captivates the hearts and minds of geneticists, archaeologists, and paleoanthropologists all over the world.

Once the researchers tested and reconfirmed their findings, they realized the significance of their discovery. This little sample of DNA from ancient history had profound implications for the field of Paleoanthropology, and for the history of humanity.

The story began in Siberia when German researchers stumbled upon a tiny fragment of bone. At first, there was nothing remarkable about the piece. But after careful testing and identification, they discovered that it came from a hominin, a term which means “species of human”. But which type of human? The researchers were unable to say. Soon they began to ponder the mysteries of the fragment.

So, what did they find? After careful analysis, researchers were able to determine exciting facts that shed new light on how ancient people, our distant ancestors, lived during their time. Using this little fragment of bone, they began to piece together a picture of a young girl from ancient times – a young girl with a fascinating heritage.

As well as studying ancient animals, researchers have uncovered valuable information by studying our ancestors, humans who walked the earth thousands and millions of years before us. The German researchers believed that a small bone fragment from Siberia could be another piece to the puzzle. They worked hard to uncover secrets about the girl from the past.

Homo Sapiens first emerged approximately 200,000 to 300,000 years ago and are considered early modern humans or anatomically modern humans. It has been said that the earliest known human ancestors were called Australopithecines. 

Australopithecines were found in Africa. It is believed that this species of human survived for about 900,000 years before reaching extinction. They vanished because of changes in their environment, by a rapidly changing climate.

Because of their increased mental capacity, they discovered a carnivorous diet that may have helped them adapt to changes in their environment.

This species has been found in parts of Africa and Eurasia. Experts suggest that they were like modern people in appearance and ability – one of the reasons why they were able to perform simple tasks with tools. 

Scientists also believe that this was when social groups and complex social interactions became commonplace as they teamed up to take down larger animals, sharing food after a successful hunt. Despite all of these advantages, they still went extinct.

The researchers at Gran Dolina dug through 11 different layers of rock. There they found various fossils of animals and humans. Reports say that on the sixth layer, the team found human remains thought to be 780,000 years old, making them the oldest human fossil found across Europe to date.

Many of their traits can be compared to that of modern humans. Researchers say that the Homo forerunner had a brain approximately 1,000 cubic centimeters in size, whereas the modern human has 1,350 cubic centimeters. Homos are described as “similar to a modern human, but more robust”.

Research also tells us that 390,000 years ago, in the era of the Middle Pleistocene, several species were said to have split off from our common ancestor. This might have marked the emergence of modern humans.

Researchers have spent many years studying how each of these species would have reproduced. Although many studies had proven it possible, the question was – did interbreeding take place amongst early humans? It was an impossible question to answer until a group of German researchers made their breakthrough with one little fragment of bone.

Michael Marshall, a contributor at Forbes, wrote in his 2018 article that “it is a myth that two different species cannot interbreed”, citing the mule, the mutual offspring of a donkey and a horse, as an example. While the word ‘hybridization’ might be new for some, the concept has been around for a long time.

According to modern medicine, animals born with an odd number of chromosomes do not have a normal cellular arrangement. From birth, they have a genetic code that inhibits them from reproducing further. Mules cannot go on to make more mule decedents. The line stops at the first generation.

However, scientists believe that Home Sapiens began mating with Homo neanderthal after migrating from Africa to the rest of the world. From this, we know that interbreeding did take place in the past, with ancestors of those people still living today.

But Homo Sapiens wasn’t just mating with Homo Neanderthal. It seems that at some point in the distant past, Homo Sapiens also coupled with those from other parts of the human species called the Denisovans.

In 2010, a team of German researchers from the Max Planck Institute released the results of their research after analyzing a tooth and finger bone found in the Altai Mountains, Siberia. They announced that they had found a new species of an ancient human.

However, it seems that the fossil they found was not enough to interpret the data thoroughly. But the researchers were in luck. in 2012, they discovered another fragment of bone in the same place in Siberia. Since then, a few other fossils have been uncovered in the caves. Through testing, it has become known that the genes of this species were carried on through people in parts of China and South-East Asia today.

Samantha Brown of the University of Oxford, a well-known archaeologist immersed in the field of Denisovan research, analyzed the proteins inside the bone fragments and it was realized that the animal fossils that were found inside the cave belonged to a human, not to animals.

The one-inch bone fragment, which would be indistinguishable from an animal bone or rock to the naked eye, came from the body of a teenage girl who was likely 13-16 years old. She died approximately 90,000 years ago. But there was more to the story.

Slon was ecstatic when she spoke about her findings on National Geographic in 2018. All the evidence told them that the child had a Neanderthal mother. While they expected the father to be a Neanderthal as well, this was not the case.

However, Slon thought something was a little off about the test. At first, she doubted the validity of the results, believing that a mistake had been made. She thought that someone had altered the data without her knowledge, or perhaps that someone had spoiled the test and had attempted to make it look like an accident. Whatever the case, Slon double-checked her work.

Another surprise was waiting in store for the research team as they analyzed the bone fragment. Slon found the teenage girl’s genetic makeup to be remarkably varied as a whole. This is where the word Heterozygosity comes in.

To put that in English, a lack of heterozygosity in your genes means that your parents were probably closely related. An abundance of heterozygosity means that your parents came from varied backgrounds, perhaps even different species. In that case, your heterozygosity levels would be incredibly high.

Slon discovered one of the most important findings in the school of evolution theory – the first generational interbreeding between species. Slon and her team were very proud of their achievement. Species interbreeding was just a concept before, but with a piece of evidence in their hands, they had turned it into a fact of history.

The researchers considered their own discovery incidental. They were looking to expand their knowledge of Denisovans, yet they uncovered something new – something incredibly valuable in the field of genetics and science in general. It raised new questions on species interbreeding. How common was it? Would they find more DNA like this?

Finding the bone fragment might have just been a stroke of luck, but maybe not. There are other explanations and theories – one of which is that the two species of hominin interbred with each other on a regular basis.

In 2018, scientists conducted genetic research on a few of the fossils of ancient humans, 23 to be exact. Even with such a small sample size, the tests revealed that the ancestors of at least two specimens had a history with species interbreeding.

Homo Sapiens, meaning “wise human” (possibly an ironic term) have been walking on the planet for about 300,000 years. They are the modern humans that you see around you today. Both you and I are Homo Sapiens. The oldest fossils of our descendants were found in Africa.

With this in mind, Pääbo had assumed that interbreeding between different species only occurred rarely and that discoveries regarding interbreeding would be few, making verification difficult.

Pääbo concluded that ancient humans interacted, and when they did, they interacted pretty freely with one another. What an incredible discovery!

“We aim to find out where they lived, when they came into contact with modern humans, and why they went extinct,” said project leader Katerina Douka, of the Max Planck Institute. Denisova Cave, where they first found Denny’s bone, is the sole source, and as of the moment, only a few handfuls of fossils have been found there.”

In this study, researchers processed the proteins present in an 800,000-year-old tooth. Using its proteins, they analyzed the genetic code of the ancient man, and the results were surprising. The DNA of the enamel was so different that it did not fit the DNA of Neanderthals or the Denisovans.

How do these developments change our views of our ancestors? David Reich, the Harvard University geneticist, said “discoveries transform and change our views of the world, and this is something that we should be excited about.”

Caves served as “houses” for the ancient people, where they sheltered themselves from the elements. And since there probably wasn’t enough space to go around, the different species probably found themselves bunking up with strange bedfellows from time to time.

The Max Planck Institute added that usually human groups in ancient times were very small and they had a high mortality rate. Broadening their social groups was one of the few ways they could improve their chances of survival. It was a good strategy.

Joshua Akey, a researcher from Princeton University agrees that Denny’s DNA points the way to a new study concerning species interbreeding. But this still has a long way to go. Scientists are hoping to find more clues in the next few years.

The University has started its funding for protein-centric research. Perhaps in the future, they will uncover more connections between humans and our origin species. Capellini is very excited about what is to come.