Homo Naledi's Bones Were Made For Walking … and Climbing

Peter Schmid and William Harcourt-Smith / Wits University
Peter Schmid and William Harcourt-Smith / Wits University

Its bones were made for walking—and for climbing, and possibly for tool making. That’s the latest insight to emerge from the ongoing analysis of Homo Naledi, our newest human relative, discovered in 2013 in the deep, nearly inaccessible Rising Star cave system in South Africa’s Cradle of Humankind. A pair of papers recently published in Nature Communications—one on the creature’s foot, and the other on the hand—paint a more detailed picture of these small-brained creatures.  

In the foot study, a team of researchers led by William Harcourt-Smith, a paleoanthropologist at Lehman College and a resident research assistant at the American Museum of Natural History, analyzed 107 bones from the foot of H. Naledi, including one nearly complete adult foot.

“The key finding is that this is a foot that is really, really human-like in most respects,” Harcourt-Smith told mental_floss. “However, in such a human-like foot, we did also find a couple of features that aren’t so human-like.”

He points to the creature’s slightly curved bones in its toes—a more primitive feature that may have been used to climb trees. It also seems to have had an arch that was quite low, which may have affected how it could have walked long distances on two legs, Harcourt-Smith says: “That in itself is quite interesting, because it points to how these animals were experimenting with walking upright. And, of course, bipedalism defines us as being human.”

A digital reconstruction of the H. Naledi foot. (a) Dorsal view. (b) Distal view of the cuneiforms and cuboid showing transverse arch reconstruction. (c) Medial view showing the moderate longitudinal arch. Image credit: Harcourt-Smith et al. in Nature Communications

In the hand study, a team lead by paleoanthropologist Tracy Kivell, of the University of Kent’s Skeletal Biology Research Centre, studied the near-complete hand (it’s missing one wrist bone known as a pisiform) of H. Naledi that was found with the bones still partially connected—an extraordinarily rare find. Some 150 hand bones were unearthed in the cave in all.

The 26 bones show a mix of characteristics that have never been seen before in any other hominin species, they say. The wrist bones have adaptive features that would’ve helped H. Naledi use tools (though none have been discovered) that are consistently found only in modern humans and Neanderthals. On the other hand, the finger bones are curved more than most australopiths—bipedal hominids like the 3.3-million-year-old Lucy—and very different from the straight fingers of humans and Neanderthals, which indicates the creature spent a good amount of time climbing.

The H. Naledi bones have yet to be dated, which means we don't know where they fit in among our hominid relatives. "Depending on how old (geologically) the H. naledi remains turn out to be, there will be important implications for interpreting the South African archaeological record, who made the various stone tools that have been found, and what anatomical adaptations were necessary to craft these implements," Kivell said in a statement sent to mental_floss.  

The hand of H. Naledi. (a) Palmar (left) and dorsal (right) views of the right hand bones, (b) found in situ in semi-articulation with the palm up and fingers flexed. The palmar surface of the metacarpals (Mc) and dorsal surface of the intermediate phalanges (IP) can be seen. Image credit: Kivell et al. in Nature Communications

When you put together the mostly modern foot and the modern-primitive hand with other features of the H. naledi body—especially the shoulder suited for climbing and a tiny skull that is decidedly un-human like in size—you get a picture of a creature that is utterly unlike anything else in the fossil record, Harcourt-Smith says. H. Naledi’s unique suite of characteristics “really speak to a unique experiment with being upright, with some part of the time spent being in the trees and some of the time walking around on the ground,” he says.

They’re not yet sure how the creature would have walked. “We haven’t come up with a really good model how it moved yet,” Harcourt-Smith says. “It’s a real conundrum. But I can tell you this: It would’ve spending most of its time walking upright. Its heel would’ve struck the ground the way ours does, and when it was walking it would’ve [looked] distinct from us—but not that much so.”

He continues, “What’s really interesting is that we always used to think with the genus Homo that one of the hallmarks of it was being a full upright, sort of obligate, 100 percent biped. But we now have a creature that we’ve assigned to Homo based on its feet and skull, and yet it’s not really walking upright 100 percent of the time. It raises as many questions as it answers about bipeds.”

Figuring out how H. naledi moved is one of the next big areas of inquiry for the foot researchers. “We really want to reconstruct the gait of this creature,” Harcourt-Smith says. “That means working with all of the teams and coming up with a really robust biomechanical evaluation of the whole. It’ll be a few years worth of work.”

They're also going to investigate the internal architecture, he says. “We’re going to be looking at the molecular structure, and that requires very high-resolution CT scanning.”

As for the hand, Kivell too will be peering inside. “We have done microCT scans of the hand bones and will next analyze the internal bony structure—trabecular and cortical bone—which can tell us more information about function and how the H. naledi hand was used,” she told mental_floss in an email.     

While the science continues, the scientists themselves seem to still be riding the high of the discovery of this unprecedentedly large assemblage of unique bones, and excited by what they can teach us about our evolutionary past.

“When I got down there, it was fossil heaven,” Harcourt-Smith says. “There were so many different things. You never get these sort of opportunities with this amount of stuff found so quickly, and it really was an extraordinary privilege to work on. It’s not normal to get this sort of treasure trove of material in one go. It’s new territory in some ways.”

The Fossil of a Human-Sized Penguin Has Been Unearthed in New Zealand

DurkTalsma/iStock via Getty Images
DurkTalsma/iStock via Getty Images

Penguins are known for looking cute and cuddly, but if the monster penguins of the Paleocene epoch were still around today, they might have developed a different reputation. As The Guardian reports, the fossil of a new species of one of these giant prehistoric penguins was recently discovered in New Zealand, and scientists say it would have gone head-to-head with many adult humans.

The bird, dubbed Crossvallia waiparensis, stood about 5 feet 3 inches tall and weighed about 175 pounds. For comparison, emperor penguins weigh up to 88 pounds and can reach 3 feet 8 inches in height. The prehistoric bird waddled the Earth some time between 66 and 56 million years ago—shortly after the mass extinction event that wiped out the dinosaurs and marine reptiles, which were probably its main predators.

An amateur paleontologist named Leigh Love discovered the creature's fossilized leg bones on New Zealand's South Island. From those fossils alone, a team of scientists from the Canterbury Museum in New Zealand and the Senckenberg natural history museum in Germany were able to estimate the penguin's height and weight and determine that it belonged to a previously undiscovered species. The large leg bones also indicate that the animal was more reliant on its feet for paddling through the water than the penguins of today.

Crossvallia waiparensis is massive by today's penguin standards, but it's not even the largest prehistoric penguin that we know of. When carnivorous reptiles began disappearing from the world's oceans, the waters opened up for new predators like penguins to flourish. Kumimanu biceae is estimated to have weighed about 223 pounds; Palaeeudyptes klekowskii may have weighed 253 pounds and stretched 6 feet 5 inches long.

[h/t The Guardian]

Scientists Are Creating a 3D Model of an 18th-Century ‘Vampire Witch’ Who Was Tortured to Death

Tonkovic/iStock via Getty Images
Tonkovic/iStock via Getty Images

In 2014, archaeologists uncovered a skeleton in Kamień Pomorski, Poland, with a brick wedged in its mouth and stakes driven through its legs. They believed the man was put to death in the 18th century because townspeople thought he was a vampire.

Now, genetic and forensic analysis has shown that the vampire burial site didn't contain a man at all: It was a 5-foot-6-inch, blue-eyed, blonde woman who was at least 65 years old when she died. Newsweek reports that scientists at the Pomeranian Medical University in Szczecin, Poland are now making a 3D computer model of the woman’s skull, which they plan to use to recreate what her face looked like.

The Forensics Genetics Unit at the university will then build her face on a physical model from layers of plastic material and reveal it to the public within the next few months. Andrzej Ossowski, the head of the unit, told the website Science in Poland that he hopes a museum might display the rendering. “We want to show that with the help of modern methods, we are able to replace skeletons that are very common in museums with 3D models based on research,” he said.

He said that townspeople may have killed the woman because they thought she was a witch, and they gave her an “anti-vampiric” burial to prevent her from rising from her grave à la Nosferatu. The brick in her mouth was meant to weigh her down—in other burials a sickle might have been placed across the neck of the body, which would slit the revenant's throat should it try to rise.

We often think of Salem when it comes to witch trials, but they were common throughout Europe before the 19th century, and archaeologists have discovered “anti-vampiric” graves in Poland, Bulgaria, and Italy. Wondering if you might have qualified as a witch during the 17th-century period of Puritan paranoia? Find out here.

[h/t Newsweek]

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