Buzz
Humans stand alone as the only surviving members of the Homo genus—no other species from our family are left. Some, like the Neanderthals, are widely recognized, while others remain less well-known, though equally fascinating. The more we discover about these early relatives, the more we uncover what we've lost as Homo sapiens rose to dominance across the globe.
10. Neanderthals
Neanderthals, or Homo neanderthalensis, were either a close kin to modern humans or possibly a subspecies of Homo sapiens. Emerging about 250,000 years ago, they continued to thrive in isolation until roughly 28,000 years ago. This means humans and Neanderthals shared the Earth for a significant period of time. It was once believed that Neanderthals went extinct because they were too primitive to survive competition. When President Biden referred to anti-mask protests as 'Neanderthal thinking,' it revealed how enduring these outdated views of Neanderthals are.
The ongoing Covid pandemic has highlighted just how significant Neanderthals were in shaping modern humans. The interbreeding between humans and Neanderthals was far more common than previously thought, with modern humans carrying between 0 and 2% Neanderthal DNA. This genetic inheritance continues to affect us today, with some individuals experiencing more severe symptoms from Covid due to Neanderthal genes.
Modern scientists no longer view Neanderthals as simple-minded relatives of humans. We've uncovered evidence of elaborate burials, hinting at possible beliefs about life after death. They created artwork and controlled fire. There’s even evidence that they cared for ill members of their communities. The mystery remains: Why did the Neanderthals go extinct despite their impressive abilities?
9. The Red Deer Cave People
Determining what qualifies as human can be surprisingly complex, especially when all you have are a few skeletal remains. When human bones were found in the Red Deer Cave in China, researchers made an unexpected claim that sparked debate: an ancient branch of human relatives inhabited the region just 14,000 years ago.
The remains of the Red Deer Cave People revealed they were strong, had thick skulls, flat faces, large molars, and an unexpectedly small brain. These characteristics pointed to human species from over a million years ago that somehow survived until relatively recently. Unfortunately, the bones couldn’t be preserved well enough for DNA analysis, leaving their true nature a subject of controversy.
The red deer, after which the cave is named, might have been hunted by the Red Deer Cave People, as evidence of stone tools was found alongside the remains, suggesting they had a complex society. However, there is skepticism about whether these people were an entirely separate species. Could they have been a subspecies, or simply modern humans with unusual physical traits? More research is needed.
8. Homo luzonensis
Caves are prime locations for finding the remains of our early ancestors. They served as shelters for ancient humans, and the forces of floods and rainfall often carried bones into them, gathering the remains in one spot. Given this, it's not surprising that many human relatives have been discovered in caves. Recently, a new species was uncovered in a cave on the island of Luzon.
The Callao cave contained seven teeth and six bones, leading to the identification of a new human relative species. Homo luzonensis lived on Luzon around 60,000 years ago. The remains show a mix of modern and ancient traits, rarely seen together in the same species. The bones also suggest these humans were smaller than modern humans, possibly due to Island Dwarfism, a condition where species shrink when living on islands. Deer bones in the cave showed signs of being butchered with tools, though no tools were found, implying that Homo luzonensis may have processed their meat outside the cave before bringing it inside to eat.
Since the Philippines is separated from Asia by water, the ancestors of Homo luzonensis must have made a difficult journey across the sea to reach the island by boat.
7. Homo habilis
Homo habilis, often called 'handy man,' earned its name from its likely role as the creator of some of the earliest stone tools in human history. This species, which lived from approximately 2.3 to 1.6 million years ago, shows that the ability to craft tools predates the emergence of Homo sapiens.
The first evidence of Homo habilis came from a solitary tooth discovered in Tanzania in 1959. It wasn’t until additional skeletal remains were found that this species was classified separately. The fossils reveal that Homo habilis had a considerably smaller brain size than later hominids, but this did not hinder their skill in making tools, such as those used for skinning animals and butchering meat.
We have gained considerable knowledge about Homo habilis from their fossilized bones. Their long arms suggest they spent time in trees. Some evidence even points to the possibility that they were predominantly right-handed, as seen from the wear patterns on their teeth, which indicate they may have held food in their right hand while pulling.
6. Homo erectus
Homo erectus was one of the most successful human species, thought to have evolved in Africa around two million years ago. Some populations may have survived until as recently as 250,000 years ago in parts of Indonesia.
The widespread fossil discoveries of Homo erectus indicate that this species rapidly expanded beyond Africa, with evidence of their presence found throughout Asia. Their ability to adapt to environmental changes, which created new habitable regions, played a significant role in this spread. Additionally, their partial carnivorous diet likely contributed to their extensive range, as carnivores must travel far to hunt, making it easier for them to discover new areas to inhabit.
Homo erectus exhibited some of the most prominent brow ridges seen in early human species. While there was initial speculation that these thick ridges provided skull protection, it is now believed they served a social purpose, possibly aiding in communication or signaling—much like how modern human eyebrows function today.
5. Homo ergaster
Homo ergaster, a close relative of Homo habilis, lived in Africa about 1.5 million years ago. They appear to have been more similar to modern humans, with some individuals reaching heights over 6 feet. The structure of their pelvises suggests they could give birth to babies with large heads, a trait shared with modern humans.
In addition to their physical prowess, Homo ergaster demonstrated impressive technical abilities. The 'ergaster' portion of their name, which means 'work,' was given due to the large stone tools found alongside their remains. Their tool use likely supported their nomadic lifestyle, as their body shape helped them endure the hot and arid environments they traversed.
In contrast to some other hominid species, there seems to be a clear distinction in height between males and females. This variation may reflect different roles for males and females within their society or culture.
4. Australopithecus afarensis
Australopithecus, while a more distant relative compared to some of the species listed here, has provided valuable insights into human evolution. Evolving around 3.9 million years ago, they became one of the earliest primates capable of walking upright for extended periods.
Evidence for their bipedalism comes primarily from their skeletal remains, but a remarkable discovery at Laetoli, Tanzania, provides near-conclusive proof. The site contains a series of footprints left in volcanic ash around 3.9 million years ago. While it's impossible to definitively identify the species responsible, Australopithecus is the most plausible candidate.
Further evidence of Australopithecus's place in human evolution comes from a cave in South Africa, where bones from Australopithecus, Paranthropus, and Homo species have been found, all deposited within a few thousand years of each other about 2 million years ago.
3. Homo floresiensis
The discovery of Homo floresiensis in 2004 shocked the world. Often called ‘Hobbits’ due to their tiny size, these individuals were found on the island of Flores in Indonesia. The adults stood at a mere 1.1 meters (3 feet 7 inches) tall. Surprisingly, Homo floresiensis survived up until around 50,000 years ago, making them a relatively recent member of the human family tree.
Homo floresiensis is believed to have evolved through a process known as island dwarfism. On isolated islands, where large predators are scarce, species often shrink in size. This allows them to thrive in environments that can support many smaller individuals. This phenomenon was also seen in the dwarf Stegadon, a type of elephant found on the island. Homo floresiensis is thought to have hunted these Stegadons, as evidenced by numerous Stegadon bones, some showing signs of butchery. Despite having brains just a third of the size of modern humans, Homo floresiensis were adept at creating tools.
The timing of the arrival of modern humans seems to have aligned with the extinction of Homo floresiensis. If humanity is solitary today, it might be because our ancestors were responsible for the extinction of many of our distant relatives.
2. Homo naledi
In 2013, a group of cavers exploring the expansive Rising Star Cave system in South Africa stumbled upon fragments of hominid fossils that were unlike any previously discovered. In total, more than 1,500 bone fragments from at least 15 different individuals were recovered. This represents the largest collection of hominid fossils found at a single site in Africa.
The fossils have been classified as belonging to a single species known as Homo naledi, a name derived from the Sotho word for star. Homo naledi exhibited a combination of both modern and archaic characteristics. While the wrists and ankles appeared modern, the chest and small brain were more reminiscent of older hominid species. Some researchers believe that Homo naledi may have evolved alongside early humans.
One of the most debated aspects of the discovery is the theory that the bodies may have been intentionally placed in the cave for burial. To access the cave's deepest parts, a source of light would have been necessary. Given the absence of flooding in the cave, it seems improbable that the bodies were simply washed in. Could Homo naledi have purposely carried their dead into the cave for burial? Further research is needed.
1. Denisovans
The advent of DNA analysis has dramatically transformed our understanding of species, leading to many unexpected revelations. What were once obscure bone fragments gathering dust in museum drawers can now be analyzed to define a species in its entirety. This was the case with the Denisovans.
Despite having only a limited number of bones and teeth, researchers were able to extract DNA, revealing that these remains belonged to a human population that could either be a separate species or subspecies. The DNA analysis showed that the Denisovans were more genetically similar to Neanderthals than to modern humans. Nevertheless, humans and Denisovans did interbreed, and in some current populations, up to 8% of their genome could be traced back to Denisovans.
A fascinating discovery about the Denisovans is that they thrived at high altitudes. It’s possible that the adaptations seen in modern Tibetans for living in the Himalayas stem from their Denisovan ancestors.
