Fossils Are Filling Out the Human Family Tree

By Anonymous

The more fossils we find, the more we learn that many kinds of humans have lived on Earth.

ImageFossils Are Filling Out the Human Family Tree
A reconstructed Neanderthal skeleton, right, and a modern Homo sapiens skeleton, left.CreditCreditFrank Franklin II/Associated Press

Homo sapiens is a pretty impressive species. We built the pyramids, landed on the moon and connected the internet. All of our successes are the fortunate result of a tremendous evolutionary journey from ape to the hominins who would become modern humans.

Along the way, other human relatives emerged and disappeared. Most lived before we did; some of the more recent ones met up with our species before going extinct, for reasons that are still mysterious to scientists.

On Wednesday, researchers welcomed the newest long-gone relative: Homo luzonensis. Here’s a quick guide to some of the other archaic humans that filled out the branches on our evolutionary tree, and what we have learned from them.

ImageFossils Are Filling Out the Human Family Tree
Cave art in the El Castillo Cave in Spain that uranium-series dating revealed to be more than 37,000 years old, suggesting they were possibly authored by Neanderthals.CreditPedro Saura/Agence France-Presse — Getty Images

Our most famous ancient relatives, the Neanderthals trotted across Eurasia some 400,000 to 40,000 years ago. Their bones were first discovered in 1856 in a cave in the Neander Valley in Germany.

Neanderthals shared the world with Homo sapiens for a while, which led to competition — and interbreeding. Today only people of purely African descent do not have Neanderthal DNA coursing through their veins.

In the early 20th century, Neanderthals were thought of as simple-minded brutes. But research over the past decades has helped burnish their reputation. Neanderthals, it turns out, made art, crafted jewelry, may have used speech, and even buried their dead.

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Layers of sediment revealed by a museum guide in the Denisovan Cave in Siberia.CreditBrendan Hoffman for The New York Times

When it came to interspecies breeding, early Homo sapiens didn’t just mate with Neanderthals. We also partnered with another ancient hominin species known as Denisovans. Traces of the encounters exist in modern DNA, too, especially in people who have roots in parts of East Asia. (Denisovans mated with Neanderthals, as well.)

The first Denisovan bone, a molar, was discovered in 1984 in the Denisova Cave in Siberia. But it wasn’t until 2010 that researchers identified the species after extracting DNA from a pinkie bone. They later sequenced the entire Denisovan genome. Some Denisovan remains uncovered so far are more than 100,000 old, and others may be just 30,000 years old.

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A 600,000 year old jaw belonging to Homo heidelbergensis, found in Germany in 1908. Creditdpa picture alliance/Alamy

Homo heidelbergensis peered at the world through robust protruding brow ridges some 700,000 to 200,000 years ago. A mandible belonging to this ancient human relative was identified by a German scientist named Otto Schoetensack in 1908 near Heidelberg, Germany, and its fossils have been found in Africa and Europe.

Sometimes this species is referred to as Homo rhodesiensis, because of very similar fossils found in what is now Zambia. Some scientists think that Homo sapiens, Neanderthals and Densiovans all may have descended from Homo heidelbergensis.

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Homo naledi fossils on display in Johannesburg.CreditJohn Hawks/Agence France-Presse — Getty Images

Deep within a dark limestone cave in South Africa in 2015, paleoanthropologists discovered the bones of an ancient human relative called Homo naledi.

Within the Dinaledi Chamber of the Rising Star Cave, the researchers discovered more than 1,500 fossilized remains from 15 individuals. The bones were between 335,000 and 236,000 years old. Homo naledi adults are believed to have been about 4 feet 9 inches tall.

Last year researchers published a study that looked at the brain impressions left on the skulls of some Homo naledi specimens and concluded that despite their diminutive size, members of the species had a brain that had similarly complex structures to our own.

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A cast of a skull belonging to H. floresiensis, the "Hobbit" person. CreditRichard Lewis/Associated Press

Nicknamed the “Hobbit” because of its small stature — measuring only about 3 feet 6 inches tall — this tiny hominin was discovered in Liang Bua cave on the island of Flores in eastern Indonesia in 2003 by an archaeologist named Michael Morwood.

The specimen was one of about a dozen such individuals that have since been discovered on the island. Homo floresiensis fossils date to as recently as 60,000 years ago. But there are also 700,000-year-old fossils on the island that may have come from their ancestors. In addition to their small bodies, Homo floresiensis had small brains, about as big as a chimpanzee’s.

A study published in 2018 tried to determine whether the current population of Flores had any genetic links to Homo floresiensis. Though the researchers found evidence of Neanderthal and Denisovan DNA among villagers, they came up short of Homo floresiensis DNA.

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Paleoanthropologist Richard Leakey in 1977 holding an Australopithecus skull in his right hand, and that of Homo habilis in his left.CreditMarion Kaplan/Alamy

Homo habilis was discovered in Tanzania in the early 1960s by a group led by Louis and Mary Leakey, a married pair of paleoanthropologists. It was dubbed the “handyman” because it was thought to have made stone tools.

This species lived in eastern and southern Africa between 2.4 million and 1.4 million years ago. Of the multiple species in our genus, Homo habilis is the least humanlike in its anatomy and most similar to apes, according to the Bradshaw Foundation.

Scientists found that for nearly 500,000 years, Homo habilis lived alongside Homo erectus in eastern Africa, a prehistoric gathering of multiple species of the Homo group, presaging the period when Homo sapiens would cohabitate in Eurasia with Neanderthals and Denisovans.

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Homo erectus fossils at the Sangiran Museum and Early Man Site in central Java, Indonesia.CreditAgoes Rudianto/Anadolu Agency, via Getty Images

In 1891, a Dutch anatomist named Eugène Dubois explored the muddy banks of the Solo River on Java, Indonesia. There, he uncovered the skullcap and thigh bone of a creature that appeared to be something between ape and modern man.

The femur indicated that it walked upright. At first, he labeled the find Anthropopithecus erectus, an upright “man-ape.” But after further inspection, he changed the name to Pithecanthropus erectus, an upright “ape-man.”

Today scientists call it Homo erectus, but popular audiences know Dr. Dubois’ discovery as Java Man. The first specimen was about half a million years old, but other Homo erectus fossils are nearly 2 million years old; they have been found throughout Asia and Africa. The species is believed to have lived from about 1.89 million to 143,000 years ago, making it the longest surviving hominin species — about nine times as long as Homo sapiens has been around, according to the Smithsonian.

More recent reporting on ancient human lineages

Nicholas St. Fleur is a science reporter who writes about archaeology, paleontology, space and other topics. He joined The Times in 2015. Before that, he was an assistant editor at The Atlantic. @scifleur Facebook