Were Neanderthals More Than Cousins to Homo Sapiens?

These members of the genus Homo have long occupied two different branches on the family tree. But now that researchers think these groups interbred, scholars are giving serious consideration to whether we are the same species after all.

Around 200,000 years ago, in what is now northern Israel, a small band of tech-savvy humans dragged home and dismembered a bounty of wildlife. Using exquisitely pointed flint spearheads and blades, they hunted and butchered myriad prey, including gazelles, deer, and now-extinct aurochs, the ancestors of modern cattle.

In the cool, humid climate of the coastal plain, these early Homo sapiens foraged for acorns in nearby forests of oak, olive, and pistachio. They ate the saline leaves of shrubby saltbush and lugged ostrich eggs back to the cave, where they slurped down the yolks.

This vision of the past comes from Haifa University archaeologist Mina Weinstein-Evron. In 2002, she and her colleagues discovered the upper jaw and teeth of a H. sapiens that dated to between 177,000 and 194,000 years old in Israel’s Misliya Cave, with animal bones and sharp tools nearby.

It’s probable, Weinstein-Evron explains, that these humans migrated to the Arabian Peninsula more than 200,000 years ago, trekking along lush corridors out of Africa. “We don’t know how many crossed, and how many of them perished, and how many went back. We only know that these people arrived,” she says.

We also know that they were likely not alone. Based on small finds of teeth and bones from local caves, “we know that the area was inhabited by Neanderthal-like creatures,” or the predecessors of Neanderthals, at that time, says Tel Aviv University anthropologist Israel Hershkovitz, an expert on modern human origins.

While out foraging, H. sapiens may have mated with these Neanderthal-like inhabitants. In this land that later birthed the Bible, they likely knew each other in the Biblical sense.

The Misliya Cave in northern Israel may have seen early human habitation some 200,000 years ago. Reuveny/Wikimedia Commons

The humans* who lived in the Misliya Cave were part of a population that, many scholars suspect, ultimately died out. Later waves of H. sapiens that left the African continent succeeded in reproducing and spreading out. But braided into the story of those human migrations is that of Neanderthals, hominins—members of our family tree closest to modern humans—who may have first evolved in Europe from African ancestors some 400,000 years ago.

Many scientists now suspect that H. sapiens and Neanderthals met and mingled their genes multiple times. Geneticists have documented how Neanderthal genes survive today among modern humans, evidence of some earlier instances of interbreeding.

New studies, made possible in part by computational techniques that enable researchers to analyze huge quantities of genetic data, show that H. sapiens and Neanderthals interbred far more than previously imagined. Indeed, their proclivity for pairing off has led many researchers to question the old dictum that Neanderthals and H. sapiens were separate species.

Such ideas raise questions as to what it really means to be a distinct “species.” They also raise the possibility that perhaps H. sapiens did not outcompete Neanderthals into extinction, as some scientists have suggested. Rather, one species may have simply absorbed the other—and so, Neanderthals, in a sense, could survive in us.

In 1856, in the Neander Valley of Prussia (now Germany), limestone cutters discovered the partial skeleton of a thick-boned, brow-ridged hominin in a cave. A German anthropologist named Hermann Schaaffhausen examined the bones.

Schaaffhausen realized that the skull differed from that of modern humans but concluded it could nonetheless belong to what he called a “barbarous and savage race” of human. However, his contemporary, Irish geologist William King, disagreed.

This fragment, found in what is today Germany, comes from the skull of a Neanderthal.
This fragment, found in what is today Germany, comes from the skull of a Neanderthal. DEA Picture Library/Getty Images

King noted that the skull of this fossil, with its “strong simial [apelike] tendencies” was “generically distinct from Man.” In 1863, King declared it a new species, which he named Homo neanderthalensis.

Scientists have been arguing over whether H. sapiens and H. neanderthalensis are truly separate species ever since. By appearances alone, Neanderthal fossils resemble ours—they are clearly members of our hominin family tree. But on closer examination, Neanderthal features are also quite distinct.

There was debate back and forth: Was this just a weird variant of us—a more primitive, brutish-looking thing than living humans—or was it really something different?” asks physical anthropologist and evolutionary biologist Jeffrey Schwartz of the University of Pittsburgh.

Schwartz can rattle off a raft of anatomical differences between H. sapiens and Neanderthals: H. sapiens are flat-faced; the Neanderthal face sticks out. Neanderthals had boxy, stout bodies, and their major arm and leg bones were thick. H. sapiens, by contrast, have thinner, gracile bodies. Neanderthals had different teeth and thumb lengths, as well as longer collarbones.

The argument might have been confined to questions of anatomy had it not been for a singular discovery in 2010. A team led by evolutionary geneticist Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, extracted bits of DNA from Neanderthal fossils and published an early version of the Neanderthal genome.

Bcomparing portions of the Neanderthal genome with the genomes of five modern-day humans—from Southern Africa, West Africa, Papua New Guinea, China, and France—they found that Neanderthals share more genetic snippets with humans in Europe and Asia today than with people living presently in much of sub-Saharan Africa.

Pääbo and his team’s findings showed that between 1 and 4 percent of the genomes of modern non-African humans consist of Neanderthal DNA. That overlap suggested, for the first time, that our H. sapiens ancestors could have had intimate encounters with Neanderthals.

This 450,000-year-old jaw from Tautavel, France, held by a paleontologist, came from an archaic human.
This 450,000-year-old jaw from Tautavel, France, held by a paleontologist, came from an archaic human. Raymond Roig/AFP/Getty Images

That study would be the first of many to indicate that these two hominins interbred. And such studies matter to the question of whether Neanderthals and H. sapiens are one or two species because, by biologist Ernst Mayr’s “classic definition,” Hershkovitz explains, “if two organisms can breed and produce fertile offspring, it means that they belong to the same species.”

Genetic research has long faced a challenge in scale. There are an estimated 21,000 genes in the human genome that code for proteins, complex molecules that do most of the work in cells and play crucial roles in the body. Sequencing these genes involved studying the 3 billion DNA base pairs that make up the human genome.

Every advance that makes studying an individual genome cheaper, more accurate, and faster is a major step forward in understanding how individuals—whether H. sapiens, Neanderthal, or other—compare. For all of those reasons, the development of artificial intelligence (AI) techniques, which enable researchers to set computers to solving problems and conducting analyses, has been a game changer.

AI has not only helped to confirm earlier genetic findings that H. sapiens and Neanderthals interbred, but also suggested their sexual encounters occurred to a degree that scholars never anticipated. All of this builds the case that the two could be the same species.

In 2018, for example, research published by population geneticists Fernando Villanea and Joshua Schraiber, then at Temple University in Philadelphia, made use of an AI tool called a deep learning algorithm, which seeks patterns in complex layers of data and is inspired by the brain’s approach to acquiring knowledge.

Computer scientists “train” algorithms by instructing them to identify specific patterns based on previously assembled data. In this case, Villanea and Schraiber used an algorithm to spot Neanderthal ancestry.

The pair then analyzed the distribution of Neanderthal DNA in the genomes of about 400 contemporary East Asians and Europeans, people whose ancestors have lived in these regions for a long time. This data came from the 1000 Genomes Project, an international collaboration to catalogue human genetic variation.

By the “classic definition,” explains anthropologist Hershkovitz, “if two organisms can breed and produce fertile offspring, it means that they belong to the same species.”

Schraiber and Villanea found fragments of Neanderthal ancestry: about 1.5 percent in each individual and 1.7 percent among people in East Asia specifically. Fabrizio Mafessoni, an evolutionary geneticist at the Max Planck Institute for Evolutionary Anthropology, reviewed Schraiber and Villanea’s findings and argued that the proportion of Neanderthal fragments among modern humans was a bit higher than would be expected if there had only been one episode in which these two populations mated.

The intuitive explanation,” Schraiber says, “is that there were multiple episodes of interbreeding and that [populations in East Asia] interbred more.”

A 2019 study, co-led by Oscar Lao, who studies population genomics at Spain’s National Center of Genomic Regulation, and Jaume Bertranpetit, an evolutionary biologist at Pompeu Fabra University in Barcelona, used deep learning algorithms to identify a hitherto-unknown human population, a hybrid of Neanderthals and Denisovans. (The Denisovans are archaic hominins identified from the Denisova Cave in the Altai Mountains of Siberia.)

Their data showed that—given the distribution of Neanderthal DNA in various living human groups—Neanderthals interbred with Denisovans in East Asia, creating the Neanderthal-Denisovan population, and their hybrid descendants did the deed with modern humans before their arrival in Australia some 60,000 years ago.

That evidence for “admixing” between Neanderthals, Denisovans, and modern humans, Bertranpetit says, indicates “that all of these populations belong to a single lineage.”

Still other research, published in 2017, indicates that gene flow from early H. sapiens into Neanderthals might have occurred earlier in humanity’s story—around the time that the Misliya Cave H. sapiens were sucking the yolks of those ostrich eggs.

That study, led by Cosimo Posth, an archaeogeneticist at the Max Planck Institute for the Science of Human History in Jena, Germany, examined DNA collected from an approximately 120,000-year-old femur bone excavated in a cave in southwestern Germany.

A researcher examines a Neanderthal fossil with protection on so as not to contaminate the sample’s DNA.
A researcher examines a Neanderthal fossil with protection on so as not to contaminate the sample’s DNA. Max Planck Institute for Evolutionary Anthropology via Wikimedia Commons

Specifically, they turned to mitochondrial DNA, genetic information handed down from mother to child and found within the cells’ energy-generating structures called mitochondria. The analysis concluded that the ancestors of Neanderthals and H. sapiens interbred at some point between 270,000 and 220,000 years ago, most likely in the Levant.

Taken together, these studies strengthen the case that H. sapiens-Neanderthal pairings occurred and that such mating was by no means unusual. Rather, H. sapiens, Neanderthals, Denisovans, and their hybrids all interbred (hinting, yes, that all three were the same species). And that mixing may have occurred as early as some of the first forays of modern human ancestors out of Africa.

For hundreds of thousands of years, modern humans as well as archaic humans, such as Neanderthals and Denisovans, have been … crossing modern-day borders that, of course, were not existing in the past and multiple times admixing and exchanging genetic material,” Posth says. “This was not the exception but was the norm.”

If “species” is defined in large part by the ability to breed and have young who can also reproduce, one might argue that Neanderthals and H. sapiens are indeed one species. And many of the scientists who work on these studies agree. Yet some experts still contend otherwise.

Approximately 75 kilometers south of the Misliya Cave, Hershkovitz is sitting in his tiny office in Tel Aviv. Around him, the skulls of H. sapiens—the oldest dating back 15,000 years—jostle with one another on shelves lining the walls.

These skulls, which belonged to living, breathing human beings, evoke an aura of a long-forgotten world. And once, earlier still, such humans coexisted with other hominin species. Yet determining how different these species were from each other is difficult. Hershkovitz, for example, sees H. sapiens and Neanderthals as “sister populations” within the same species.

Anthropologist Israel Hershkovitz stands by a cast of human remains in his office.
Anthropologist Israel Hershkovitz stands by a cast of human remains in his office. Josie Glausiusz

But Mayr’s “classic definition” of a species, based on interbreeding, is riddled with exceptions. For instance, if members of two different species happen to reproduce, they can have offspring but that new generation of “hybrids” may not be able to reproduce.

A horse and a donkey’s offspring, the mule, is typically sterile, for example. But lions and tigers, separate species that in the wild live on different continents, can sire “ligers” or “tigons” in captivity, and those hybrid felines can rarely or occasionally reproduce. In other words, scientists recognize instances where two species remain separate despite interbreeding—and some researchers extend that exception to H. sapiens and Neanderthals.

New York University biological anthropologist Shara Bailey believes H. sapiens and Neanderthals reproduced but remained distinct species—just like lions and tigers. She describes the two hominins as morphologically separate species who diverged from each other at least 800,000 years ago.

For all intents and purposes, they were separate species,” Bailey says, “but they maintained the ability to hybridize.” Their offspring, she argues, would have been rare and, though able to reproduce, less successful in reproducing compared with their parents. The genetic record, then, indicates that some hybrids did sometimes succeed, contributing Neanderthal DNA to the modern human gene pool.

Bailey’s not alone in this viewpoint. Anthropologist Chris Stringer, at the Natural History Museum in London, also concludes that these populations both were separated long enough in terms of their evolution and were physically distinct enough in their features to remain separate species that occasionally hybridized.

Given the complications in Mayr’s definition, some scholars argue it ought to be replaced. To that end, there are now 20 different conceptions of what a “species” could be—and no strong consensus on which should take center stage. Some scientists subscribe to the theory of species mate recognition, in which members of the same species “recognize” one another as mates through courtship rituals, breeding seasons, or protein compatibility.

Untold Homo species contributed to the eventual emergence of both Neanderthals and Homo sapiens.
Untold Homo species contributed to the eventual emergence of both Neanderthals and Homo sapiensFiorella Ikeue/SAPIENS

And at least one researcher still questions the genetic evidence for interbreeding. Schwartz says he has seen and studied almost every specimen of the entire human fossil record and notes that “Neanderthals are clearly a different species from us: They are so morphologically unique.”

Schwartz doubts the interpretation of genetic evidence thus far. Although dozens of hominins once existed, Schwartz points out, scientists have only sequenced the genomes of three specimens whose species they could clearly identify by their morphology: modern H. sapiens, the Neander Valley Neanderthal, and a 400,000-year-old hominin called Homo heidelbergensis. (Researchers have endeavored to identify the species of other, fragmentary specimens, primarily using genetic clues derived from the definitively identified Neanderthal and H. sapiens fossils.)

Because we don’t know how many hominin species there were—and because the vast majority have not had their DNA sequenced—we can’t know how many of these hominins had genes that were specifically “Denisovan” or “Neanderthal,” Schwartz argues. Therefore, he says, there is no way of knowing whether the DNA sequences extracted from Neanderthals were exclusive to Neanderthals.

Pääbo and his group are very good technicians,” Schwartz says. “I don’t doubt that they have really worked hard to make sure these sequences are not contaminated.” Still, he says, we lack the DNA of many other hominins. The evidence that the sequenced DNA is specific to Neanderthals is therefore unreliable, he argues, and so claims that they interbred with H. sapiens are also dubious.

I’m not saying that the comparisons are incorrect or that the sequences are incorrect,” Schwartz says. “I’m saying that the conclusion is not that solid.”

Schwartz doubts that Neanderthals and H. sapiens would have recognized each other as mates: “Neanderthals don’t look like us; we don’t look like them; they wouldn’t move the same way we did,” he says. Also, “they probably smelled different than we do.”

For the moment, then, the answer to whether or not H. sapiens and H. neanderthalensis were the same species is still up for debate (along with the entire messy concept of “species”). But the larger message that comes through with each wave of findings is simple: Despite a long history of derogatory “cave man” descriptors, H. neanderthalensis was probably a lot like us.

The first time H. sapiens and Neanderthals met was likely in the region that is now Israel. Just as the Misliya Cave helps establish how long anatomically modern humans were present in the region, tools associated with Neanderthals, such as spearheads and knives, have been found in other caves in Israel.

But many mysteries remain. Did H. sapiens and Neanderthals whisper sweet nothings to each other beneath the leaves of a pistachio tree? Was there some secret lure, facial or pheromonal, that attracted one to the other? We can only speculate.

Archaeologists fit together chipped stone pieces that may have been tools crafted by Neanderthals at a Stone Age site in northern Israel.
Archaeologists fit together chipped stone pieces that may have been tools crafted by Neanderthals at a Stone Age site in northern Israel. Netta Mitki /PLOS ONE

Neanderthals were intelligent; they were skilled toolmakers. We don’t know whether they had spoken language, because even though they had vocal anatomy similar to H. sapiens, the soft tissue associated with the vocal box—the area of the throat containing the vocal cords—has not been preserved.

Both H. sapiens and Neanderthals shared a propensity for primping. Neanderthals made jewelry out of animal teeth, shells, and ivory. They decorated themselves with feathers and probably ochre as well.

Some scholars suspect that fierce competition between H. sapiens and Neanderthals pushed the latter from the warmer Levant into an ice-covered Europe. “The world was almost empty,” Hershkovitz says. “The way I personally see this—probably most people would not agree with me—the European Neanderthals had no other choice.”

Though Hershkovitz declines to conjecture as to whether female Neanderthals were forced into sex—rape has been used as a weapon of war through the ages to punish and terrorize—he does offer, “I don’t think it was a happy marriage.”

Others, including Schraiber, posit more peaceful encounters. “I imagine that when humans ran into some vaguely human-like thing, they were like, ‘This is cool,’” he speculates. But, he demurs, “I really don’t know, Did they whisper sweet nothings beneath the leaves of a pistachio tree? We can only speculate.especially since I’m not an anthropologist, I’m a geneticist.”

At least one researcher, computational biologist Rasmus Nielsen of the University of California, Berkeley, goes further. He hypothesizes that Neanderthals never went extinct: They, or their genes, were simply absorbed into modern humans. In other words, instead of dying out through violence or starvation, the Neanderthal population hybridized with H. sapiens.

Using mathematical models, Nielsen and his colleague Kelley Harris have argued that at one point, the proportion of Neanderthal DNA in humans alive today was as high as 10 percent—and that proportion later dwindled. That 10 percent figure is significant because other researchers have estimated H. sapiens outnumbered Neanderthals 10-to-1, so perhaps, Nielsen contends, the two species interbred to such an extent that they merged together.

Over time, however, modern humans lost significant amounts of Neanderthal DNA, perhaps because it carried harmful mutations. Indeed, another research team, which included Pääbo, found that most Neanderthal genes survive in H. sapiens in regions of non-coding DNA. “The regions that are most important for function—the protein-coding genes—are depleted of Neanderthal DNA,” Nielsen says.

In a Q&A for the journal BMC BiologyNielsen and Harris write: “It is possible that Neanderthals did not truly die off at all but simply melted together with the human species. One could perhaps argue that Neanderthals did not disappear due to warfare or competition—but due to love.”

If they are right, then whether we were once one species or two does not matter because we are all one now.


*Editor’s note: Many anthropologists use the term “human” to not only mean modern Homo sapiens but also many other hominin species on our family tree. (In other words, for some scholars, Neanderthals have always been “human,” as members of the genus Homo.) In our story, we use “human” broadly while using “H. sapiens” to refer to the only living species of the Homo lineage and “modern humans” to point to “all humans living today.”

Scientists Put a Human Intelligence Gene Into a Monkey. Other Scientists are Concerned.

#9 in our top science stories of 2019.

By Teal BurrellDecember 29, 2019 2:00 PM
Monkey Barcode - Shutterstock
(Credits: Macaque, Glass and Nature/Shutterstock; DNA Barcode, Zita/Shutterstock)
Scientists adding human brain genes to monkeys — it’s the kind of thing you’d see in a movie like Rise of the Planet of the Apes. But Chinese researchers have done just that, improving the short-term memories of the monkeys in a study published in March in the Chinese journal National Science Review. While some experts downplayed the effects as minor, concerns linger over where the research may lead.

The goal of the work, led by geneticist Bing Su of Kunming Institute of Zoology, was to investigate how a gene linked to brain size, MCPH1, might contribute to the evolution of the organ in humans. All primates have some variation of this gene. However, compared with other primates, our brains are larger, more advanced and slower to develop; the researchers wondered whether differences that evolved in the human version of MCPH1 might explain our more complex brains.

Su and his team injected 11 rhesus macaque embryos with a virus carrying the human version of MCPH1. The brains of the transgenic monkeys — those with  the  human  gene —  developed at a slower pace, akin to that of a human, than those in transgene-free monkeys. And by the time they were 2 to 3 years old, the transgenic monkeys performed better and answered faster on short-term memory tests involving matching colors and shapes. However, there weren’t any differences in brain size or any other behaviors.

But the results aren’t what has the scientific community buzzing. Some individuals question the ethics of inserting a human brain gene into a monkey — an action Rebecca Walker, a bioethicist at the University of North Carolina, argues could be the start of a slippery slope toward imbuing animals with humanlike intelligence. In a 2010 paper, James Sikela, a geneticist at the University of Colorado School of Medicine, and coauthors asked whether a humanized monkey would fit into its society, or would  live in inhumane conditions due to its altered genes.

To justify the work, Su and his co- authors suggested that it could provide insights into neurodegenerative and social disorders — but they don’t describe what those applications might be. “I don’t really see anything in the paper that would make me think that [the experiment] was necessarily a good idea,” says Walker.

Su declined Discover’s request for comment, but said in an article for China Daily, “Scientists agree that monkey models are at times irreplaceable for basic research, especially in studying human physiology, cognition and disease.” And in the research paper, the authors contend that the “relatively large phylogenetic distance (about 25 million years of divergence from humans) … alleviates ethical concerns.” (Rhesus macaques are less like humans in terms of social and cognitive capacities than primates such as chimpanzees, which are more closely related to us.) This greater  evolutionary distance suggests it would be harder to wind up with a macaque that acts like a human.

But that reasoning falls flat for Walker. “It doesn’t really matter when they became differentiated from humans on the phylogenetic tree,” she says. “They’re talking about improved short-term memory, which would be putting them sort of closer to us in terms of those cognitive abilities.” She thinks manipulating these skills makes the work ethically dubious and requires stronger justification.

“While monkeys and humans have similar genomes,” Su said in the China Daily article, “there are still tens of millions of genetic differences. Changing one gene carefully designed for research will not result in drastic change.”

Sikela agrees that such a change may be minor. Still, he wonders about the possibility of finding a gene with a large effect on cognition.

“There’s some risky elements to going down this road,” Sikela says. “One needs to think about the consequences of where this is leading and what’s the best way to study these kinds of questions.”

Walker also worries about where this work leads. “Could we enhance human brains through these methods?” she asks. While she thinks we’re nowhere close to that yet, she notes that science can advance surprisingly quickly. For instance, CRISPR — the gene-editing technique that once seemed far removed from human research — was used in China to edit the genomes of twins in 2018. (See our No. 11 story of the year, page 32.)

“It does feel worrisome to be doing this research in primates,” Walker says. “And then potentially thinking about how that could be used in humans.”

You’re Not So Different From an Octopus: Rethinking Our Relationship to Animals

Remember back when we were all tubes?

Sy Montgomery does. That was a simpler time, eons before the octopus and Homo sapiens went their separate evolutionary ways, and certainly long before that highly intelligent cephalopod, which appeared some 300 million years ago, ended up boiled, stewed and fried. “Our lineage goes back a half-billion years ago when everyone was a tube,” says Montgomery, a naturalist and author of many books about animals. “That was when there were no eyes. Yet we have evolved almost identical eyes. I just love that.”

Montgomery’s enthusiasm and devotion to Earth’s creatures — and the similarities we share with them — has inspired her readers to get to know the eight-tentacled and big-brained wonders in The Soul of the Octopus, and taken us to the ends of the Earth and back to our own backyards in such award-winning books as Spell of the Tiger and Birdology.

A real-life Dr. Dolittle, Montgomery says she’s always related best to animals and — sometimes straining the patience of her bipedal family members — has long treated her home as a land-bound ark for orphaned animals. In scientifically precise but poetic prose, she writes that we share greater similarities than differences with the electric eel, the tarantula, the tree kangaroo and the snow leopard. Don’t forget, she says, that we hail from the same genetic pool, or more likely, gurgling swamp. By paying attention to the commonalities we have with our fellow animals — our singular capacity for what Montgomery argues is a broad range of emotions and zeal for life — humans can transcend the “we-shall-rule-the-Earth” anthropocentric focus, she says, and see that we are all in this together.

“We are on the cusp of either destroying this sweet, green Earth — or revolutionizing the way we understand the rest of animate creation,” Montgomery said. “It’s an important time to be writing about the connections we share with our fellow creatures. It’s a great time to be alive.”

Montgomery recently chatted with Leslie Crawford, author of animal-focused children’s books Gwen the Rescue Hen and Sprig the Rescue Pig, and compared notes on delving into the minds of animals.

Leslie Crawford: Do you understand animals more than people?

Sy Montgomery: As a child, I grew up on an Army base and I did not have a single human friend. It allowed me the freedom to get to know other species. I vividly remember my 20s like it was yesterday. As a young person, I was often worried about whether or not I was reading other people correctly. And yet these are organisms that use the same English language. It’s terrific to be in my 60s and know I can read animals. I have always read animals better than people.

What did you find surprising about humans as a child?

I was shocked to learn that people use their language to lie. Even little kids lie. Of course, animals will lie, too. A sea snake will say, I’m three or four sea snakes. Chimpanzees lie all the time. But the degree to which humans use language to lie shocked me. I’ve always dealt with animals in a very straightforward way. I wasn’t ever trying to conceal things from them. Humans often want incorrect information about you and project incorrect things on you.

So much has changed about our understanding of animals since you started writing about them. When did you first realize that animals are sentient beings?

I think most of us realize as children that animals are sentient beings. But then, somehow, for so many people, this truth gets overwritten — by schools teaching old theories, by agribusiness that wants us to treat animals like products, by the pharmaceutical and medical industries who want to test products on animals as if they were little more than petri dishes. But thankfully, scientific and evolutionary evidence for animal sentience has grown too obvious to ignore.

What have you learned about animals and consciousness?

You don’t want to project onto animals your wishes and desires. You have to respect your fellow animals. I don’t want to roll in vomit, but a hyena would enjoy that. I don’t want to kill everything I eat with my face, but that’s what I’d do if I’m a great white shark. If I were eating a carcass, I would not be as happy about it as a scavenger. We have different lives but what we share is astonishingly deep, evolutionarily speaking.

When did you know you were an animal person?

Animals have always been my best friends and the source of my deepest joy. Before I was 2, I toddled into the hippo pen at the Frankfurt Zoo, seeking their company, and totally unafraid. When I learned to speak, one of my first announcements to my parents was that I was really a horse. The pediatrician reassured my mother I would outgrow this phase. He was right, because next I announced I was really a dog.

My father loved animals. Growing up, my mother had a dog named Flip who she adored. But I seem to have had an even greater attachment to animals than they did. My friend, the author Brenda Peterson, says that I must have been adopted at the local animal shelter.

How many animals do you currently live with?

Right now, the only animal who lives with us is a border collie named Thurber. I travel a lot: Thailand, Ecuador, Germany, Spain. I can’t force my husband to have a house filled with animals. I had chickens but predators got almost all of them. Weasels got into the coop. They are so smart. Even though we buried wire beneath the floor, weasels need just a tiny opening to get through. You can never weasel-proof an old barn.

It sounds like you have some respect for weasels even though they killed your chickens?

They were there first. I learned my chickens were killed on Christmas morning when I brought a bowl of popcorn to them and saw this white creature with black eyes staring at me. You’d think I’d be angry. But the beauty and ferocity of this creature filled me with awe. At the same time that I mourned my beloved chickens, I admired the weasel.

You originally studied psychology. How do you go about thinking about what animals are thinking? Or is it a mistake for people to imagine animals are thinking in a way that we think?

I triple majored in college, and psychology was one of them. But thinking about animals wasn’t really part of the coursework. I think it’s perfectly reasonable to assume that nonhuman animals share our motivations and much of our thought processes. We want the same things: food, safety, interesting work and, in the case of social animals, love. But we can’t always apply human tastes to animals — otherwise fish would seek to escape from the water and hyenas wouldn’t roll in vomit.

When did you stop eating meat and dairy and why do you think some people make the decision and others don’t?

I read Animal Liberation, by Peter Singer, in my 20s. Even though I loved meat, I haven’t eaten it since. I can’t wait to try the Impossible Burger!

In writing Sprig, I learned so much about pigs, including how smart they are. What do you love most about pigs?

They are so sensitive and emotional. And they’re wise. They know what matters in life: warm sun, the touch of loving hands and great food.

Similarly, when I wrote Gwen, I found out how remarkable hens are with their own superpowers, including keen eyesight and a strong community that includes watching out for each other.

I agree with you. I love these aspects of their lives. I love how similar they are to us in so many ways, but I also love the otherness of these animals.

Speaking of “otherness,” in your book Soul of an Octopus, you came to know Athena, an octopus, as a friend. But can a person really know an octopus?

Until the day I met Athena in 2011, pretty much all of the creatures I got to know personally were vertebrates. We are so like fellow mammals, with whom we share 90 percent of our genetic material.

I didn’t know if I would be able to bring what I understand about other animals to an invertebrate, but I was delighted to see it was true of the octopus. It was clear the octopus was just as curious about me as I was about her.

There are some animals who aren’t interested in you. But when you have an octopus look you in the face and investigate you with her suckers with such an intensity, well, what that octopus taught me [about consciousness] blew me away. When Athena grabbed me, I correctly understood that she wasn’t being aggressive, just curious.

How do you convince people to consider an octopus as something other than something to eat?

I tell them about my octopus friends, Octavia and Kali and Karma — specific individuals to whom they could relate.

I have realized that preaching to people about seeing animals as worthy of the same compassion and dignity as is owed humans doesn’t work. But if preaching isn’t effective, what do you think works to change hearts and minds — and stomachs?

Teach by example. It’s the most powerful tool we have. Your love for pigs, told through your stories of Sprig and Gwen, is contagious because of your example. You show how much fun it is to let these animals enrich your life and make others want to be part of it. That’s much more appealing than a lecture.

Are there one or two calls to action you would ask of people who want to improve the world for animals?

I would suggest that individuals find the action that best suits them. For me, when I was young, working 14 hours a day and making relatively little money, I had no extra time for volunteer work, and my tithes to animal causes amounted to far too little. But I could change my diet, so I did. For another person, an overnight change to vegetarianism or veganism might be too tough, but perhaps they could volunteer at a shelter.

I personally hate politics, though I vote and donate. But other people might throw themselves joyously into working toward electing candidates that support conservation and animal welfare legislation. Happily, we can all work with our individual strengths to make the change animals deserve.

What about everything we learn daily about climate change and the growing risk of mass extinctions?

Sometimes you don’t want to read the headlines. It’s so depressing. During the civil rights movement, I was too young to have anything to do with that. But now we can choose to be part of what is definitely a movement, one that recognizes that nonhuman animals think and know and feel the way we do. We know this based on cognitive and behavioral science. That change has happened within my lifetime, which is fantastic.

The fact that we live during a challenging time gives us an opportunity to be courageous. I’m thrilled to be able to apply my courage to such a worthy endeavor and with such worthy partners.

This article was produced as part of a partnership between Stone Pier Press and Earth | Food | Life, a project of the Independent Media Institute.

Did Humans Survive an Extinction Level Event?

November 30, 2019  Topic: History  Region: Europe  Blog Brand: The Buzz  Tags: EvolutionHumansExtinctionAnthropologySurvival

Warfare became a check on population growth, perhaps the most important one.

Nine human species walked the Earth 300,000 years ago. Now there is just one. The Neanderthals, Homo neanderthalensis, were stocky hunters adapted to Europe’s cold steppes. The related Denisovans inhabited Asia, while the more primitive Homo erectus lived in Indonesia, and Homo rhodesiensis in central Africa.

Several short, small-brained species survived alongside them: Homo naledi in South Africa, Homo luzonensis in the Philippines, Homo floresiensis (“hobbits”) in Indonesia, and the mysterious Red Deer Cave People in China. Given how quickly we’re discovering new species, more are likely waiting to be found.

By 10,000 years ago, they were all gone. The disappearance of these other species resembles a mass extinction. But there’s no obvious environmental catastrophe – volcanic eruptions, climate change, asteroid impact – driving it. Instead, the extinctions’ timing suggests they were caused by the spread of a new species, evolving 260,000-350,000 years ago in Southern AfricaHomo sapiens.

The spread of modern humans out of Africa has caused a sixth mass extinction, a greater than 40,000-year event extending from the disappearance of Ice Age mammals to the destruction of rainforests by civilisation today. But were other humans the first casualties?

Human evolution. Nick Longrich

We are a uniquely dangerous species. We hunted wooly mammoths, ground sloths and moas to extinction. We destroyed plains and forests for farming, modifying over half the planet’s land area. We altered the planet’s climate. But we are most dangerous to other human populations, because we compete for resources and land.

History is full of examples of people warring, displacing and wiping out other groups over territory, from Rome’s destruction of Carthage, to the American conquest of the West and the British colonisation of Australia. There have also been recent genocides and ethnic cleansing in Bosnia, Rwanda and Myanmar. Like language or tool use, a capacity for and tendency to engage in genocide is arguably an intrinsic, instinctive part of human nature. There’s little reason to think that early Homo sapiens were less territorial, less violent, less intolerant – less human.

Optimists have painted early hunter-gatherers as peaceful, noble savages, and have argued that our culture, not our nature, creates violence. But field studies, historical accounts, and archaeology all show that war in primitive cultures was intense, pervasive and lethal. Neolithic weapons such as clubs, spears, axes and bows, combined with guerrilla tactics like raids and ambushes, were devastatingly effective. Violence was the leading cause of death among men in these societies, and wars saw higher casualty levels per person than World Wars I and II.

Old bones and artefacts show this violence is ancient. The 9,000-year-old Kennewick Man, from North America, has a spear point embedded in his pelvis. The 10,000-year-old Nataruk site in Kenya documents the brutal massacre of at least 27 men, women, and children.

It’s unlikely that the other human species were much more peaceful. The existence of cooperative violence in male chimps suggests that war predates the evolution of humans. Neanderthal skeletons show patterns of trauma consistent with warfare. But sophisticated weapons likely gave Homo sapiens a military advantage. The arsenal of early Homo sapiens probably included projectile weapons like javelins and spear-throwers, throwing sticks and clubs.

Complex tools and culture would also have helped us efficiently harvest a wider range of animals and plants, feeding larger tribes, and giving our species a strategic advantage in numbers.

The ultimate weapon

But cave paintingscarvings, and musical instruments hint at something far more dangerous: a sophisticated capacity for abstract thought and communication. The ability to cooperate, plan, strategisemanipulate and deceive may have been our ultimate weapon.

The incompleteness of the fossil record makes it hard to test these ideas. But in Europe, the only place with a relatively complete archaeological record, fossils show that within a few thousand years of our arrival , Neanderthals vanished. Traces of Neanderthal DNA in some Eurasian people prove we didn’t just replace them after they went extinct. We met, and we mated.

Elsewhere, DNA tells of other encounters with archaic humans. East Asian, Polynesian and Australian groups have DNA from Denisovans. DNA from another species, possibly Homo erectus, occurs in many Asian people. African genomes show traces of DNA from yet another archaic species. The fact that we interbred with these other species proves that they disappeared only after encountering us.

But why would our ancestors wipe out their relatives, causing a mass extinction – or, perhaps more accurately, a mass genocide?

13,000-year-old spear points from Colorado. Chip Clark, Smithsonian Institution

The answer lies in population growth. Humans reproduce exponentially, like all species. Unchecked, we historically doubled our numbers every 25 years. And once humans became cooperative hunters, we had no predators. Without predation controlling our numbers, and little family planning beyond delayed marriage and infanticide, populations grew to exploit the available resources.

Further growth, or food shortages caused by drought, harsh winters or overharvesting resources would inevitably lead tribes into conflict over food and foraging territory. Warfare became a check on population growth, perhaps the most important one.

Our elimination of other species probably wasn’t a planned, coordinated effort of the sort practised by civilisations, but a war of attrition. The end result, however, was just as final. Raid by raid, ambush by ambush, valley by valley, modern humans would have worn down their enemies and taken their land.

Yet the extinction of Neanderthals, at least, took a long time – thousands of years. This was partly because early Homo sapiens lacked the advantages of later conquering civilisations: large numbers, supported by farming, and epidemic diseases like smallpox, flu, and measles that devastated their opponents. But while Neanderthals lost the war, to hold on so long they must have fought and won many battles against us, suggesting a level of intelligence close to our own.

The Conversation————————————————————————————————————–

Nick Longrich, Senior Lecturer, Paleontology and Evolutionary Biology, University of Bath

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Image: Reuters

The problem with bears in our backyards isn’t a bear problem at all; it’s a human one

Bear-human conflict increases substantially in years when natural foods fail.


Kyle Artelle is an adjunct assistant professor at the University of Victoria and a biologist with the Raincoast Conservation Foundation.

Last month, in Penticton, B.C. a group of five black bears – three males and two younger females – had been spotted feasting on residents’ garbage. Conservation authorities were called in, and the five bears were shot dead. This came just a week after six bears were shot in a three-day period near Kelowna. These bears – who have grown accustomed to humans and are comfortable in our proximity – are deemed “conflict bears” in the conservation community.

Unfortunately these incidents were anything but anomalies. This year there has been a substantial increase in the number of bears killed across B.C. The common response to these kinds of conflicts is to focus on the bears themselves: killing bears, relocating bears, or having a fear of humans instilled in bears. Hunters will even argue that the best solution to reducing human-bear conflict is to hunt more bears, with the assumption that fewer bears will lead to less conflict.

Unfortunately, these responses are at best misguided, and often counterproductive. The truth is that the root of bear-human conflicts has little to do with bears – and a lot to do with us. However, better co-existence with our ursine neighbours is possible, based on solid understanding of bears, problem human behaviour and the ecology of bear-human conflict.

Research my colleagues and I have conducted has found that in the long-term, killing so-called conflict bears does not seem to affect conflict patterns in the long-term. Similar research has found the same in Ontario, Colorado, and elsewhere. You kill some conflict bears, and others will replace them.

An understanding of the ecology of conflict between bears and humans reveals another important insight: although, the saying “a fed bear is a dead bear” can certainly be true when bears become too dependent on human food, bears who venture near human habitation in years of particularly poor natural food availability do not necessarily return the next year, if natural food conditions improve.

This is perhaps not a surprise given bears’ preference for human avoidance: other than in extreme garbage-conditioning cases, if natural foods return, so too should avoidance of people.

Key to effectively addressing bear-human conflict is instead realizing that for the most part, it’s not bears that need to be managed – but people. Conflict can be thought to arise from two inter-related processes: proximate causes, such as someone’s garbage drawing a bear into their yard or someone surprising a mother grizzly bear with her cub, and ultimate or ecological causes, such as humans encroaching into bear territory or loss of natural foods. When we start to see bears coming into towns and backyards it is helpful to avoid knee-jerk reactions and to instead ask: why? Finding out what is actually driving the pattern will inform effective solutions.

Poor attractant management is by and large the most consistent problem human behaviour. Although bears generally avoid human habitation, persistent human food sources (for example, fruit trees, garbage, compost) can be too hard to resist, especially in late summer and fall when bears are desperately trying to pack on the pounds pre-hibernation. Treating this as a bear problem is to propel an unending cycle that not only results in the needless killing of bears but also in a waste of time and energy.

It is also helpful to understand the ecological context. Our research in B.C. has found that bear-human conflict increases substantially in years when natural foods fail. Examples of this include poor salmon returns, berry failures, or similar. This highlights the importance of management that takes an ecosystem approach, for example managing to ensure sufficient berries on the landscape, and fisheries management that ensures sufficient salmon for bears. An ecological understanding can also be used to predict when conflict might be at its worst. Years with poor natural food availability could signal a need for extra vigilance and management of problem human behaviour.

There have been some promising developments highlighting how we can shift toward a more informed and effective approach to mitigating bear-human conflict. For example, Port Moody recently increased the fines for improperly stored garbage by 10-fold – with repeat offenders facing fines of up to $1,000 – in an effort to reduce the number of black bears killed each year.

In Bella Coola, a provincial hot spot for grizzly bear-human conflict, the Nuxalk First Nation-led Bear Safety program takes a holistic approach to conflict mitigation involving public education and programs that work with landowners to take measures such as removing attractants and constructing strategic electric fencing.

Although managing landscapes and fisheries with bears and other wildlife in mind is not yet the norm in B.C., there are some promising cases of where it is increasingly being taken into account. For example, a number of Coastal First Nations explicitly consider the needs of bears and other salmon consumers in their salmon stewardship planning.

A recent report commissioned by Raincoast Conservation Foundation and produced by the University of Victoria’s Environmental Law Centre offers policy reforms that could improve agency responses to conflict, including independent oversight and a shift toward a more restrained (and less lethal) response to conflicts.

This year’s high rates of bear-human conflict have been frustrating and upsetting for many. This is in many ways more of a symptom of our own behaviour than that of bears. The sooner we can learn from successful examples of bear-human co-existence and adjust our focus to our own behaviour, the sooner the widespread and consistent stories of bears being shot in cities and towns of B.C. and beyond could become a thing of the past.


Am I an Anti-Natalist?

If children were brought into the world by an act of pure reason alone, would the human race continue to exist? Would not a man rather have so much sympathy with the coming generation as to spare it the burden of existence, or at any rate not take it upon himself to impose that burden upon it in cold blood?~ Arthur Schopenhauer 

I have been accused of being an anti-natalist. The accusations suggest my particular variety of anti-natalism is congruent with life as a serial killer. Because I do not appreciate being called such names without supporting evidence, I decided the issue was worth a quick etymological investigation.

The definition of natalism, according to the Merriam-Webster online dictionary, is “an attitude or policy favoring or encouraging population growth.” The definition includes no mention of serial killers. Indeed, the definition mentions no murder of any kind.

I decided not to have children of my own at the age of 19 years. At the time, it made no sense to me to bring another human into the world without his or her permission, particularly in light of the publication of Limits to Growth seven years earlier. It still makes no sense to me. So far, I have succeeded in my personal quest to avoid adding more people to Earth.

I explained the horrors of continued growth of the human population for more than two decades in college and university classrooms. Few students took my advice seriously. I learned to not be attached to the outcome of my efforts, in the classroom and beyond. I thank my students for serving as my teachers.

I dedicated my first book-length work of social criticism, Killing the Natives, “to those who selflessly stop at zero.” Based on the responses I subsequently received, you would have thought I was suggesting we murder all babies, human and otherwise. That was not my point.

I am no fan of continued growth of the human population. At more than 7.7 billion and growing rapidly, I think there are plenty of us.

I am no fan of death. I am no fan of extinction, human or otherwise.

I know I will die. I am pretty sure you will die. I know our species, Homo sapiens, will go extinct. The only serious questions about death and extinction involve cause and timing.

I am certain my own death and extinction of Homo sapiens will occur soon. I am still no fan of death. I am still no fan of extinction, human or otherwise.

Apparently I am an anti-natalist. Apparently, based upon logic, I need not apologize for donning this label.

Too many humans, combined with an astonishing rate of consumption, have brought us to the brink of extinction. Too late to turn back now, I do not judge, shame, or blame people for bringing more humans to life. I am an educator, not a judge.


Thanks to muse Mimi German for inspiring this essay


Who is holding up the war on global warming? You may be surprised

Who is holding up the war on global warming? You may be surprised
© Getty Images

The good news is that the American public finally appears to accept that global warming is a problem. The bad news is that a substantial percentage of the public is unwilling to pay much to do anything about it. At first glance these may seem to be contradictory messages. But the public may be reacting to the initial symptoms of a warming planet rather than the dire consequences envisioned by the scientific community if global warming remains unchecked.

This explanation is supported by recent findings that a majority of Americans believe that the weather-related disasters we have been experiencing are becoming more severe and that the main culprit is a warmer global climate. But what the public foresees for the future is unclear. The outlook may be unambiguous to climatologists. But does the public buy into what the science shows about the implications of failure to reduce greenhouse emissions?

If the answer to this question is “no,” then it may help explain why a substantial share of the public gives such low priority to efforts to address longer-term climate change risk. Many people simply do not yet believe that continued procrastination will likely have catastrophic consequences for society and the environment. Perhaps a well-paid opposition has been more successful in sowing doubt than we had feared.

But in any event, if the adage “to see is to believe” plays a dominant role in shaping public attitudes, we are in trouble. Due to lags in the climate system, it will take decades for many of the effects of today’s emissions to play themselves out. By then, we will likely have committed the planet to much of the damage we fear the most.

Most troublesome is that, if the public is fixated on what they can see on a given day, season or year, they will be vulnerable to the machinations of those who see cold snaps as confirming that global warming is a ruse. They argue that short-term deviations are explained by the natural variability in local weather.

For example, a U.S. senator once brought a snowball on to the Senate floor as proof that climate change is a hoax. That year (2015) turned out to be the hottest in recorded history until that time.

So, what has the public seen to date? The government provides an exhaustive accounting of deaths, direct economic losses and other impacts for natural disasters whose frequency and intensity are associated with climate warming. Those disasters include heat waves, severe storms, hurricanes, droughts, floods, wildfires, famines and sea level rise. Accounts of such events are also increasingly reaching the public eye, either when people look out their kitchen windows or when they turn on the evening news. What is stunning is how fast damages have risen over the past four decades.

So what can we do? Much has been written about the need for better communication and better education. Those are no-brainers. But there is other work to be done, including addressing this fundamental question: What is driving current public attitudes about climate change? That’s where we need to focus more of our resources. Good natural science is critical, but so is research into the behavioral science behind the public’s attitudes.

Public opinion isn’t the only barrier to action. Lawmakers need to play a far greater role in combatting this existential challenge. They naturally carefully judge the mood of the public, with eyes on polls that reflect their electability. When a sufficient fraction of their constituents tilt towards action, they will be happy to jump to the front of the parade. Hopefully, when that finally happens it will not be too late.

Five bears killed after coming too close to elementary school in Penticton, B.C.

Animals drew dozens of complaints since the summer, says conservation officer

These five bears travelled together in a pack in the Okanagan city of Penticton, B.C., before being put down by conservation officers on Thursday. (Submitted by Tobe Sprado/Conservation Officer Service)

Five bears were destroyed by conservation officers in Penticton, B.C., Thursday after the group ventured too close to an elementary school.

Tobe Sprado, an inspector for the Okanagan region with the B.C. Conservation Officer Service, says the service has received 44 complaints about these particular bears since August.

“We were hoping that we’re going to be able to coexist with these bears,” Sprado said. “But things had escalated over that period of time.”

Sprado said the bears were attracted to garbage and fruit, and were starting to cause property damage.

On Wednesday afternoon, things escalated after one of the bears charged a person out walking.

“That [was] an aggressive behaviour that definitely put these bears more on our radar,” Sprado said.

“Then when they entered into the vicinity of the elementary school, we ended up making the decision to put down all five bears.”

The children and teachers were kept inside until the bears were shot dead.

Bears can cause problems in towns and cities as they look for food to eat before winter hibernation. (Submitted by Rachel Rowbottom)

Unusual grouping

Sprado said the bears would travel together in a pack, unusual for black bears. The group comprised three adult male bears and two females who were sub-adults.

“It wasn’t your typical sow with the cubs at all … [it’s] a bit of an anomaly from what we’re used to dealing with,” he said. “They could be a bunch of siblings.”

Sprado said his team was emotionally drained and frustrated by the turn of events.

It comes a little over a week after six bears were shot in the space of three days in the area of Lake Okanagan Resort northwest of Kelowna. In that case, the bears were eating garbage that hadn’t properly been secured and had lost their fear of humans.

An undisclosed company near Kelowna was fined $230 and ordered to improve the way it stores its garbage.

Sprado implored people to safely secure bear attractants like garbage, fruit, as well as pet food, bird feeders, barbecues and compost.

The truth about bovines, badgers and the spread of TB

Convention held that humans had caught tuberculosis from cattle – but the DNA record tells a different story
Badger and cow
 The UK’s proposed large-scale cull of badgers to control the spread of TB in cattle has been postponed. Photograph: Natural Visions/Alamy

Mycobacteria and TB have been in the news a lot recently. In fact, one particular species has been hogging the limelight: Mycobacterium bovis. As its name suggests, it likes to infect cows, but as we’re recently all too aware, it’s quite happy in badgers too.

There are about 120 species of mycobacteria. They’re rod-like bacilli with a thick, waxy cell wall. The “human” member of the Mycobacterium family (using this word conversationally, as Mycobacterium is of course a genus, not a family, taxonomically) is M tuberculosis. From its point of view, it’s very successful. From our point of view, it’s the most important bacterial disease that afflicts us, causing about one-and-a-half million deaths a year.

This is how TB is caught: you breathe in tiny droplets of fluid containing just a few bacilli. In your lungs, your own immune cells move in and swallow up the bugs – but this is exactly what they want. Inside the immune cell, the bacilli replicate and pile up. More immune cells pile in. If you’re lucky, the bacilli are held tight in this lump, this tubercle. If you’re unlucky, the bugs get out and the disease spreads – through your lungs (and you start coughing up droplets with bacilli in, ready to infect someone else), through your whole body, even getting into your bones.

But this isn’t the story written in the DNA of the bacilli. In 1999, an early genetic study cast doubt on the ancestor-descendant relationship between the bovine and human forms of TB. More studies confirmed the new story. If anything, the ancestor of both human and bovine forms must have been closer to the human form – with its larger chromosome. It’s even possible that cows caught TB from us (or at least, from another mammal that had caught “human” TB).

Using molecular clocks to date the age of M tuberculosis, looking for the last common ancestor of current versions of the bug, is problematic, and has produced a great range of dates from 15-40,000 years ago. All of these easily predate farming. However, this date is likely to just record a population crash in TB, probably because of a crash in the numbers of its host. Humans (and their ancestors) could have been suffering from TB for hundreds of thousands of years before then.

Earlier this year, filming for BBC2’s Prehistoric Autopsy series, I visited Göttingen, and the lab of Professor Michael Schultz. He showed me a fascinating fossil, a piece of a Homo erectus skull, found in a travertine tile factory in Turkey. Scientific articles can be dry, stuffy things, but the one in which Michael described the fossil includes this fantastic quote: “Given the nature of its discovery in a factory workshop, the hominin was unfortunately reduced to a standard rough-cut tile thickness of 35mm.”

Despite the rough treatment of the fossil, the bone was very well preserved, and on the inner surface of the skull, Michael showed me clusters of small pits – things that just shouldn’t be there in normal bone. They were quite clearly pathological, and Michael believed that the best explanation for them, given their appearance and their position inside the skull, was meningitis caused by M tuberculosis. Here was evidence for a human ancestor suffering from TB, half a million years ago.

Back to the present, and TB has scarcely been out of the news for the past few weeks. The Great Badger Cull has become one of the hottest political potatoes of the year. So what is the scientific evidence? Well, it seems pretty clear that badgers do help spread bovine TB. But that also seems to be where the certainty ends. Bovine TB in the UK has been going up and up – but how much of that is due to better diagnosis? And could culling badgers really help to reduce it? A study published in the journal Nature in 2006 showed that culling badgers reduced the rates of TB among cattle in the area where the cull took place – but increased it in neighbouring areas. In 2011, based on the results of previous trials, scientists advised the current government that culling 70% of badgers in large areas could result in a 16% reduction in bovine TB. For the government, that was enough.

But some scientists are now concerned that the cull – particularly if carried out by free shooting, which hasn’t been trialled, or if targets are missed – could make matters worse.

For this winter, the badgers are safe. Like Caesar presiding over a bizarre gladiatorial contest, environment secretary Owen Paterson granted the badgers a stay of execution, at the eleventh hour. There are just too many of them to make a 70% cull achievable this late in the year.

So the debate continues. It’s an argument about science, politics and economics. It centres on protecting food animals from harm, just as our ancestors have done since farming first got started. But, to me, it also raises interesting questions about how we see ourselves and other animals. It’s about how much we see ourselves as a “dominant” species, entitled to subjugate the needs of other animals beneath our own. It’s about how much room we demand as a human population (with a taste for milk and beef) and how much room we’re prepared to make for wildlife.

And let’s not forget, if it hadn’t been for us, cattle and badgers might not have had TB in the first place.

It’s Not Just Fires. Your Phone Is Also Destroying The Amazon.

“You could drop a nuclear bomb on the forest, and it would be better than mining it.”

Last updated on August 31, 2019, at 12:00 p.m. ET

Posted on August 31, 2019, at 11:37 a.m. ET

Cris Bouroncle / AFP / Getty Images

An aerial view over a chemically deforested area of the Amazon jungle caused by illegal mining activities in the river basin of the Madre de Dios region in southeast Peru, on May 17, 2019, during the ‘Mercury’ joint operation by Peruvian military and police ongoing since February 2019.

The wildfires ripping through the Amazon have drawn the world’s attention to the destruction of the “lungs of the planet.” Many scientists believe cattle ranchers clearing land caused the flames, spurring groups around the world — including the government of Finland — to call for a boycott of Brazilian beef. But to boycott all of the products damaging the Amazon, you’d have to do much more than give up steak. You’d have to toss out your phone, laptop, wedding band, and anything else with gold in it.

“There’s no way to get the gold out without destroying the forest. The more acres you cut down, the more gold you get. It’s directly proportional,” Miles Silman, the cofounder of Wake Forest University’s Center for Amazonian Scientific Innovation (CINCIA), told

“There’s no way to get the gold out without destroying the forest.”

Fueling that demand is not just the world’s appetite for gold bars and jewelry — the largest categories for which gold is used — but also high tech. Tiny electrical currents are constantly running through your iPhone, Alexa speaker, and laptop — and carrying those currents is gold, a fantastic conductor of electricity that’s also resistant to corrosion. While there isn’t much gold inside a single device — an iPhone 6, for example, contains 0.014 grams, or around 50 cents’ worth — in the aggregate, the amount is staggering. According to market researcher Gartner, over 1.5 billion smartphones were sold last year, with 1.3 billion of them being Android devices. It was followed by 215 million iOS devices.

So the tech industry, which consumes nearly 335 tons of gold yearly, will only need more and more of the metal. “There’s a gold rush in the Amazon right now that’s just like the gold rush that happened in California in the 1850s,” said Silman.

According to a 2018 CINCIA study, artisanal mining, or small-scale mining conducted by independent miners, have uprooted nearly 250,000 acres of rainforest in the Madre de Dios region of Peru, where Silman focuses his work. Another study, by researchers at the University of Puerto Rico in 2015, found that approximately 415,000 acres of tropical forest across South America has been lost to gold mining. A map compiled by environmental group Amazon Geo-Referenced Socio-Environmental Information Network shows 2,312 illegal mining sites in 245 areas across six countries, which the group called an “epidemic.”

And just as the California gold rush gave rise to a lawlessness that took generations to tame, the tech industry’s suppliers can’t always meet demand and sometimes turn to the Amazon’s illegal mining economy.

Afp / AFP / Getty Images

An artisan miner shows a piece of gold after extraction and processing on May 6, 2008 in El Ingenio, Peru, 420 kms south of Lima. Artisan mining accounts for the livelihood of more than 40 thousand Peruvian families, though almost 15% of the nation’s gold production comes from this activity. Since the 1980s many extracting camps have been converted into small mining towns lacking basic services and containing high levels of pollution.

Miami Herald investigation in 2018 detailed how a handful of traders from Southern Florida–based precious metals company NTR Metals bought $3.6 billion of gold from outlaw mines across South America. NTR Metals has since been shut down and the traders arrested. The company was a subsidiary of Elemetal, a major US gold refinery that supplied Tiffany & Co. and other consumer brands, like Apple, which said it stopped working with the supplier, in corporate disclosures for the year 2017 and 2018.

Apple is far from the only tech giant that sources gold from the Amazon region. A review of corporate disclosures by BuzzFeed News found that Amazon (the company), AppleSamsungSony, and Google list refiners Asahi and Metalor as suppliers. In turn, these firms, based respectively in Switzerland and Japan, buy some of their gold from South American mines. According to the Herald, those companies buy from brokers, who source their gold from a range of legal and illegal mines in the region.

Companies like Alphabet, the parent company of Google, are aware of the impacts of gold mining in the Amazon, and have taken steps to address it. A Google company spokesperson pointed to its conflict minerals policy, and says it relies on third party audits to ensure that smelters are in compliance. Samsung, Sony, and Amazon did not return a request for comment. Apple told BuzzFeed News all its gold refiners participate in third party audits. “If a refiner is unable or unwilling to meet our standards, they will be removed from our supply chain,” an Apple spokesperson said it a statement. “Since 2015, we’ve stopped working with 60 refiners of gold for this reason.”

Dirty gold doesn’t just end up in electronics. A 2015 report by Ojo Publico reported that companies with ties to the London Bullion Market Association — an organization that determines the international price of gold — acquired precious metal from illegal mining camps in Peru, Bolivia, and Brazil.

“A part of the problem with gold is that it all goes into one melting pot. So you can have a bar of gold where some of it comes from responsible sources, some of it comes from illegal sources, but it looks like one bar of gold,” said Sarah duPont, president of the Amazon Aid Foundation.

That illegal and dirty gold extraction takes a toll on the environment and the humans who mine it. Compared to soybean farming or cattle ranching, the mining industry clears fewer acres of forest from the Amazon.

However, according to Silman, the carbon emissions of mining can make the industry’s environmental footprint between three to eight times as big as the surface acres lost to mining might suggest. In addition to uprooting trees and other plants, miners dig two to four meters deep into the ground, where soil is rich in carbon. That soil can be thousands of years old, and gold mining liberates that carbon back into the atmosphere, killing nutrients in the dirt that are vital to plants in the rainforest.

“If you think about an Amazonian forest, there’s nothing you do that’s worse to it than alluvial mining.”

“The growth rates around the mines are so slow because you’ve washed everything that’s good out of the soil,” Silman explained.

Gold mining also transforms the landscape in another way: “1 out of every 5 acres converted by mining can’t be reforested because it’s converted into a body of water. So it ends up looking like Minnesota, with thousands of lakes all across the landscape,” said Silman. “If you think about an Amazonian forest, there’s nothing you do that’s worse to it than alluvial mining. You could drop a nuclear bomb on the forest, and it would be better than mining it.”

On top of the environmental devastation, mercury, used as an amalgam to retrieve gold from the dirt, contaminates the region’s water and food supply. According to the US National Institute of Health, artisanal and small-scale gold mining is the leading source of mercury released into the environment. Researchers have found high levels of mercury, which has serious health effects on the nervous, digestive, and immune systems, in people living along the Brazil–Venezuela border, the Madre de Dios area of Peru, and in Suriname.

Joao Laet / AFP / Getty Images

Aerial view of the Esperanca IV informal gold mining camp, near the Menkragnoti indigenous territory, in Altamira, Para state, Brazil, in the Amazon basin, on August 28, 2019.

Despite the dangers, gold mining in the Amazon region is unlikely to slow down. Brazilian president Jair Bolsonaro has loosened the country’s environmental laws and is working to open up more of the Amazon to mining. Bolsonaro fired the head of the country’s agency that tracks deforestation, after a report that some 1,330 square milesof Amazonian forest in Brazil had been lost since the president took office in January — a 39% increase over last year.

What can be done? According to Kevin Telmer, executive director of the Artisanal Gold Council, an organization working to professionalize and train the sector, the environmental problem is linked to that of extreme poverty.

Banning small-scale mining would not be effective, according to Telmer: “People have asked the miners to leave for 40 years and they haven’t. What [bans] do is drive the economy into the black market.”

“What’s needed really is sustainable economic pathways for those individuals who are currently pursuing illegal mining,” said Payal Sampat, the mining program director at Earthworks, a nonprofit that started a campaign called No Dirty Gold in 2008. Sampat added that buying vintage jewelry and holding on to electronics for longer is a good way for consumers to cut down on their gold consumption.

Silman, the CINCIA researcher, agrees. Legally placed mines, he said, are at least confined to a small area, instead of thousands of mines sprawled across a landscape. Taxing mining operations could also help money flow back into job placement and other programs: “There was $3 billion made out of Madre de Dios, and a lot of it flowed through mafias. There’s a little over 100,000 people living in that land, and they would have had $300 million of tax revenue,” he said.

The formalization and professionalization of the sector can help miners be more productive, and be less impactful on the environment, too, Silman said: “Once you do all these things, at least you can get some good from mining, and you still don’t destroy all the opportunities for the future that rely on biodiversity.”