Dude, we found some more old bones!
That’s not probably the official headline you’ve seen in the last couple of weeks about this recent paleoanthropological find but it could have been.
There has been quite a bit of media coverage in the past two months about a recent discovery of a 3.8 million years old cranium from the Afar region of Ethiopia. You can read all about it here.
This new discovery is of an individual in the hominin species called Australopithecus anamensis. The big deal about this find is that it questions the currently accepted idea that Lucy, an Australopithecus afarensis dated to approximately 3.2 million years old, is the direct ancestor to subsequent Australopiths that led to H. sapiens or modern man.
It’s really an important find and a very interesting read in the above mentioned article but it’s not what this post is entirely about.
Let me do a quick 11 point recap of the last 50 years of just the Homo sapiens timeline.
In the mid 1970’s we all studied Cro Magnons. The oldest known examples of modern man. They were dated to have lived no older than 30,000 to 32,000 years ago. Cro Magnons were based on 5 skeletons found in France in 1868. In 1932 another Cro Magnon discovery was unearthed at Mount Carmel, Israel and dated to basically the same timeframe of 30 to 40K ya.
Then in the early 1980’s another Cro Magnon find in Israel and a re-examination of the previous one pushed back the timeframe to 100,000 ya. Which of course immediately more than doubled the age of man.
Then in 1967 two different fossil skull remains were found in Omo (Africa) but not accurately dated until decades later. They turned out to be 195,000 ya. Another doubling of the age for man.
So now we are at 195K and in walks Mitochondrial Eve. Mitochondrial Eve, a fictional character, was established through the study of genetics in 1987. She is the most recent woman from whom all living humans descend in an unbroken line purely through their mothers, and through the mothers of those mothers, back until all lines converge on one woman. The date for Eve was between 152 and 234 thousand years ago. A general estimate given the Omo finds was tagged at 200,000 years ago for Mitochondrial Eve. This DNA evidence along with Omo finds provided a solid foundation for establishing the 200,000 years ago mark as the beginning of Homo sapiens. This dating has been the benchmark as the consensus of opinion on the age of man for the last few decades.
And now we come to Y Chromosomal Adam who is the male counterpart to Eve. Y-chromosomal Adam is the name given to the most recent common ancestor (MRCA) from whom all living people are descended through the male lines of their family tree. Up until 2013 genetics had given the date to Adam of basically the same as Eve which is around 200K give or take.
Then in another re-examination of fossil remains a skull found in 1932 in Florisbad, South Africa using electron spin resonance dating to around between 259±35 ka (between 294,000 and 224,000 years old.
There are also fossil skull remains of the Dali skull from China found in 2017 that have been dated to 250,000 ya. Interestingly when this find was first dated the scientific community poo pooed it as nonsense. After all it was claimed modern man didn’t exist then and even if they did, they certainly didn’t leave Africa until 60,000 ya. Both assumptions we now know are totally wrong.
Then an African American man submitted his DNA to a family tree website for testing and astonishingly it tested for 338,000 years old. His heritage points to Western Cameroon in Africa. Researchers went there and found 11 other men with the same date, 338,000 years old, in their DNA. This has been baffling to scientists since then as it did not fit into any accepted model for Homo sapiens.
Then in 2017 another re-examination of skeletal remains from a cave in Morocco. Bone fragments from 22 individuals. New technological advances gave a date to the fossil remains to 300,000 to 350,000 years old.
There is a dig site in India where although there are no bone fragments there are ample other artifacts, mostly in the way of modern man’s tool kit, that establish the site as being habited by modern man, it dates to 385,000 years ago.
- Since 2018 other indications from studying DNA in Homo sapiens and Neanderthals have placed the birthing of the Homo sapiens species around 500,000 years ago or earlier.
We only know what we know at this point in time.
To me it’s pretty obvious we only know what we know. And what we know gets updated and changed on a regular basis through new finds and new technology. Here are five new species of hominin discovered since 2004.
- Homo floresiensis in 2004, found on the island of Flores in Indonesia.
- Australopithecus sediba in 2008, found in South Africa
- Homo denisova in 2010, found in the Denisova Cave in Siberia, Russia
- Homo naledi in 2013, found in South Africa
- Homo luzonensis found in 2019, from Luzon Island, Philippines
With the discovery of a new species establishing a timeline is of great importance. Anthropologists bring out the whole arsenal of dating techniques with every find of course, as you can imagine the timeline for a new species is critical to establishing at what point in the human lineage the new species fits into.
In the past, Anthropologists did the best they could with what they had but now we have so much more and so many more working on it.
90% of all the scientists that have ever lived are alive today. This simple statistic captures the power of the exponential growth in science that has been taking place over the past half century. Nowhere more evident than in the science of Anthropology. There are literally hundreds of individuals on digs everyday looking for fossils and artifacts. There are literally thousands involved in the analysis of the data discovered. Major technological advancements and upheavals are announced practically on a daily basis as the understanding of our world and our human lineage moves forward.
Skull of 1.77 million year old Rino
Paleoanthropology Game Changer
So, what is the new game changer?
DNA has been nothing sort of a revolutionary way with which researches have been able to study evolution. But DNA has a half-life of 521 years and the oldest sequence disovered so far comes a horse about 700,000 years old.
A new technique based on the study of proteomics (the study of proteins) has been discovered. Tooth enamel of a rhinoceros has yielded genetic information from 1.7 million years ago.
This is incredibly promising as it applies the paleoanthropology. The newly discovered Australopithecus anamensis I talked about earlier could in fact usurp and take the place of Lucy as a direct decedent of modern man. Many think that is already the case but with the backing of DNA analysis to support the morphological findings it would seem pretty conclusive.
We are a ways off on that but the path seems on track to one day soon find out the direct lineage of Homo sapiens. Which is not to say tomorrow another species or even an entirely new genus could yet be unearthed. There are thousands out there looking. However, with being able to unlock DNA from millions of years ago a new and deeper understanding of human evolution is upon us.