[Disturbing News]: Humans could make babies on Mars after new sperm discovery, study says

https://nypost.com/2021/06/14/humans-could-reproduce-on-mars-due-to-durability-of-sperm/

By Ben Cost

June 14, 2021 | 9:56am | UpdatedEnlarge Image

Humans could one day be able to reproduce on Mars because sperm can survive there for up to 200 years, according to a new study.

Humans could one day be able to reproduce on Mars because sperm can survive there for up to 200 years, according to a new study.NY Post composite

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There’s no need to discover life on Mars — not when we could possibly make our own.

Scientists have discovered that sperm can potentially survive on Mars for hundreds of years, meaning that humans could possibly reproduce on the Red Planet in the future.

“These discoveries are essential for mankind to progress into the space age,” lead research author Professor Sayaka Wakayama, a scientist at Japan’s University of Yamanashi, told the Daily Mail of the study.

However, no humans pleasured themselves in the name of science, per the research published Friday in the journal Science Advances. Instead, scientists studied the effects of radiation on a batch of mouse sperm that had been freeze-dried and stored aboard the International Space Station for six years.

Experts previously believed that space radiation would destroy sperm, rendering breeding impossible — or even causing cancer.

However, new analysis revealed that the rodent reproductive fluid was perfectly healthy after its interstellar sojourn. Even subjecting the spunky stuff to X-rays on Earth didn’t affect fertility.

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Lunar sperm bank could help humanity survive apocalypse

“Many genetically normal offspring were obtained,” said Wakayama, whose team estimates that freeze-dried semen could last aboard the ISS for up to 200 years.

These space-sex findings could prove a major step in our goal of becoming an interplanetary life form, something that scientists deem increasingly essential in light of dwindling resources, the Science Times reported.

“When the time comes to migrate to other planets, we will need to maintain the diversity of genetic resources, not only for humans but also for pets and domestic animals,” said Wakayama of our intergalactic propagation plans.

Sperm isn’t the only thing that can possibly survive the vacuum of space for extended periods of time. Tardigrades — also known as “water bears” — can reportedly live for 30 years without food or water and endure temperatures of 302 degrees Fahrenheit, leading researchers to deduce that these microscopic superheroes could survive on other planets as well.

No, Humans Didn’t Evolve From the Ancestors of Living Apes

https://interestingengineering.com/no-humans-didnt-evolve-from-the-ancestors-of-living-apes

The last ancestor that we shared with apes had its own set of traits, and was different from both us and modern apes.By  Marcia WendorfMay 10, 2021No, Humans Didn't Evolve From the Ancestors of Living ApesMan-Half-tube/iStockPhoto

The truth is that we don’t know where we, homo sapiens, came from. In his 1871 work, In The Descent of Man, Charles Darwin speculated that humans originated in Africa, and that we evolved from an ancestor who was different from any currently living species.

Now, a new study by an international group of paleoanthropologists, with a wide range of specialties, have backed up Darwin by concluding that it is likely that the last ancestor that we shared with apes had its own distinct set of traits that are different from those of both modern humans and modern apes.

Who was this ancient ancestor?

Chimpanzees, with whom we share 98 percent of our DNA, are in genus Pan, while humans are in genus Homo. Humans diverged from chimpanzees between 9.3 and 6.5 million years ago.Top ArticlesEngineering Failure: Man Trapped on 300ft-High Bridge After Glass ShattersREAD MOREVoyager 1 Just Heard a Cosmic 'Hum' in the Depths of Interstellar SpaceTurn Your Favorite Hot Wheels Car into a Mini-RC ModelFacebook's User Data Enables Drug Companies to Target People with Health ConditionsFossil Fuel Emergency: US Races to Move Gasoline After a Pipeline HackEngineering Failure: Man Trapped on300ft‑High Bridge After Glass Shattershttps://imasdk.googleapis.com/js/core/bridge3.457.0_en.html#goog_1640365065https://imasdk.googleapis.com/js/core/bridge3.457.0_en.html#goog_2056904514https://imasdk.googleapis.com/js/core/bridge3.457.0_en.html#goog_562727021javascript:falseSKIP ADEngineering Failure: Man Trapped on 300ft-High Bridge After Glass Shatters

Historically, two major approaches have been used in analyzing human ancestry:

  • Top-down – uses living apes, especially chimpanzees, to reconstruct our origins
  • Bottom-up – uses the fossil record of both humans and apes; it shows multiple possibilities both for what the LCA looked like, and where he roamed.

In reviewing the studies surrounding these diverging approaches, the authors of the paper argue that there are limitations to relying on just one or the other of these opposing approaches. This is because the top-down studies often assume that modern ape species share habitat and features of earlier groups, while bottom-up studies tend to give individual fossil apes a more important evolutionary role than may be warranted.

In an attempt to reconcile these approaches to identifying our ancient ancestor, the scientists looked at what the environment must have been like for the Pan-Homo last common ancestor, or LCA. 

The Miocene epoch existed from around 23 to 5.3 million years ago, and a number of fossil ape genera from that era have been found. However, they show a combination of features common to both “orthograde” (upright) and “pronograde” (walking on all fours) body plan, which has led some scientists to exclude the Miocene apes from the human lineage, and there is no scientific consensus on the evolutionary role played by these fossil apes.

The journey from monkeys to us
The journey from monkeys to us. Source: Almécija/AAAS

Some scientists espouse the theory that some Miocene apes dispersed out of Africa and into Eurasia, approximately 16 to 14 million years ago, before the hominins diverged from apes. Some of these apes gave rise to the line that produced orangutans, and the European “Dryopith” apes, while others returned to Africa where they evolved into modern African apes and hominins. Others interpret dryopiths as broadly ancestral to hominids or as an evolutionary dead end.

During the late Miocene period in Africa, increased habitat fragmentation may have led to the evolution of African ape knuckle-walking, and hominin bipedalism, or walking on two feet, from a common orthograde ancestor who lived in the trees. Walking on two feet might have allowed our human ancestors to adapt their diets and locomotion, and escape the  “specialization trap” that kept other apes in an arboreal environment.

The study concluded that future research efforts should focus on looking for Miocene ape fossils in areas where they have yet to be found. The scientists also concluded that data-driven modeling should take precedence over trying to fit evolutionary scenarios to every fossil find.

Hominin fossils have been found in eastern and central Africa, and possibly also in Europe. Fossils of over 50 genera of ancient apes have been found in Africa and Eurasia, however, as Dr. Sergio Almécija, a researcher in the Division of Anthropology at the American Museum of Natural History told Sci-News “… there is no scientific consensus on the evolutionary role played by these fossil apes.”

Kelsey Pugh, one of the study co-authors, added that, “The unique and sometimes unexpected features and combinations of features observed among fossil apes, which often differ from those of living apes, are necessary to untangle which features hominins inherited from our ape ancestors and which are unique to our lineage.”

Locations of Miocene ape fossils
Miocene ape fossil locations. Source: Source: Almécija/AAAS

Where do we go from here?

The new study seems to put us back to square one as to where we came from. Every ancient religion has its own theory of how we came to be. Giorgio A. Tsoukalos, better known as “the hair guy,” who is a producer of the show “Ancient Aliens” on which he often appears, theorizes that humans arose due to visits made to Earth made by ancient aliens. Tsoukalos shares those opinions with others including Erich von Däniken, Zecharia Sitchin, and Robert K. G. Temple.

A new bird flu jumps to humans. So far, it’s not a problem.

https://www.seattletimes.com/subscribe/signup-offers/?pw=redirect&subsource=paywall&return=https://www.seattletimes.com/nation-world/a-new-bird-flu-jumps-to-humans-so-far-its-not-a-problem/

April 21, 2021 at 1:00 pm Updated April 21, 2021 at 1:01 pm  By JAMES GORMANThe New York Times

When a bird flu virus struck a major poultry farm in Russia earlier this year, it was a reminder that the coronavirus causing the pandemic was not the only dangerous virus out there.

The authorities quickly tested the birds and moved into high gear, killing 800,000 chickens, disposing of the carcasses and cleaning the farm to stop the potential spread to other chicken farms. But they were also concerned for humans.

They tested the birds and sequenced the virus, determining that it was the H5N8 strain of avian flu, highly dangerous to both wild and domestic birds. It is established in Asia and has been increasingly causing deadly outbreaks in birds in Europe. H5N8 viruses have infected some poultry flocks in the United States, but the viruses come from a different though related lineage of virus, distinct from the current H5N8 viruses in Asia and Europe. Flu viruses combine and mutate frequently in unpredictable ways.

In the short period from Dec. 25 to Jan. 14, more than 7 million birds were lost to H5N8 outbreaks in Europe and Asia. Europe alone had 135 outbreaks among poultry and 35 among wild birds. Of course, to put the numbers in context, humans consume about 65 billion chickens each year, and one estimate puts the number of chickens on the globe at any one time at 23 billion.

As damaging as H5N8 has been to birds, it had never infected people. Until February. Russian health authorities also tested about 200 of the people involved in the cleanup of the farm in Astrakhan, using nasal swabs and later blood tests for antibodies. They reported that for the first time, H5N8 had jumped to people. Seven of the workers appeared to have been infected with the virus, although none of them became ill. Only one of those seven cases, however, was confirmed by genetically sequencing the virus.

Nonetheless, the potential danger of the new virus and its jump to humans set off alarm bells for Dr. Daniel R. Lucey, a physician and a specialist in pandemics at Georgetown University.ADVERTISINGSkip AdSkip AdSkip Ad

He began writing about the Astrakhan event in a blog for other infectious disease experts as soon as it was publicized. He reported that during a television interview, a Russian public health official said the H5N8 virus was likely to evolve into human-to-human transmission. That possibility was frightening.

“The WHO finally put out a report Feb. 26,” he said.

But it did not frame the event as particularly alarming because the virus was not causing human disease, and the report judged the risk of human-to-human transmission as low, despite the Russian official’s comment.

To Lucey, no one else seemed to be taking the infection of humans with H5N8 as “of any concern.” He added, “I think it’s of concern.”

Other scientists said they were not as worried.

Dr. Florian Krammer, a flu researcher at the Icahn School of Medicine at Mount Sinai, said he was more concerned about other avian flu viruses like H5N1 that have already shown themselves to be dangerous to people. Another avian influenza virus, H7N9, infected people for the first time in 2013. There have been more than 1,500 confirmed cases and more than 600 deaths since then. Since 2017 there have been only three confirmed cases, and the virus does not jump easily from person to person.

It is always possible that any virus can evolve human-to-human transmission, as well as become more dangerous. But H5N8 would have both hurdles to jump. Compared to other viral threats, Krammer said, “I’m not worried.”

Dr. Richard J. Webby, a flu specialist at the St. Jude Graduate School of Biomedical Sciences and director of the WHO’s Collaborating Centre for Studies on the Ecology of Influenza in Animals and Birds, said that all of the H5 viruses are of concern because some of them have infected and killed people. But, he said, “They all have the same sort of binding capacity to human cells, which is limited,” he said. Flu viruses use a slightly different way to attach to cells in birds than to cells in humans and being good at one usually means not being good at the other.ADVERTISINGSkip Ad

Webby also said that while seven infections would certainly be of concern, only one infection has been confirmed. The tests of the other six involved nasal swabs and blood antibody tests. In people with no symptoms, he said, nasal swabs can simply indicate that they had breathed in virus. That would not mean it had infected them.

Blood antibody tests also have a potential for error, he said, and may not be able to distinguish exposure to one flu virus from another.

Nor did he see any scientific basis for suggesting that H5N8 is more likely than any other bird flu to evolve human-to-human transmission. But any virus could evolve that ability.

Lucey said he was heartened to see that the U.S. Centers for Disease Control and Prevention had prepared a candidate vaccine for H5N8 before it had infected humans. Candidate vaccines are simply first steps in planning for potential problems, and have not been through any testing. They exist for many viruses.

“Humans should be routinely tested those for the virus, right at the time of the outbreak in birds,” Lucey said.

He favors the protocol followed in Astrakhan and argues that for any outbreak among birds, public health authorities should test people who are exposed to sick birds with nasopharyngeal swabs and an antibody test, followed by other antibody tests a few weeks later.

An upcoming editorial in the journal Travel Medicine and Infectious Disease also takes up the Astrakhan incident and calls for increased monitoring of all H5 viruses.This story was originally published at nytimes.com. Read it here.

Noisy humans are preventing forests from regrowing

Noisy humans are preventing forests from regrowing (msn.com)

Mike Wehner  14 hrs ago


Twin snowstorms to paste the Rockies and Northeast tonight into FridayChina attacked America as being divided as the world takes noticea close up of a bird: noise pollution © Provided by BGR noise pollution

Humans are great (well, that’s debatable) but we’re also super noisy. Think about all of the noise we make with our vehicles, machines, various types of entertainment devices, and even our voices and you’ll quickly come to the conclusion that humans as a species are one of the noisiest around. We’re so noisy, in fact, that other animals tend to avoid us. Cities often push many species away just by gobbling up their habitat but beyond that our incredible noise can make other types of animals like birds search for homes elsewhere.

Scientists have been telling us about the effects of our noise on animal life for some time, but new research is beginning to point to another side effect that many people might not even consider. Since animal groups like birds are some of nature’s most prolific seed-spreaders, it’s looking increasingly likely that humans are actually preventing the regrowth and spread of various plant species simply because we’re making the animals that plant those seeds head for the hills.More from BGR

In the study, which was published in Proceedings of the Royal Society B, researchers observed a large area of New Mexico known as Rattlesnake Canyon, which is currently under natural resource management. The region has a lot of natural gas wells, and as Guardian reports, these facilities are extremely loud. The round-the-clock ruckus is up to 100 decibels, which would be enough to cause hearing damage in humans with extended exposure. But if the noise is painful for us, it’s perhaps even worse for wildlife that often sees loud sounds as a threat.

The study covered a whopping 115 acres and multiple wells with noisy compressors. Observations of the number of trees of various ages as well as animal activity, specifically birds, began in 2007. At the time it was thought that the noise around the wells with compressors was pushing some animal life away, including birds that spread seeds, while other species were doing just fine. Hummingbirds, for instance, didn’t mind the noise, and that led to an increase in flowering plants due to their pollinating efforts.

Over a decade later, scientists once again revisited these areas to compare how things changed over time. What they found was that some wells had removed their compressors while others that were previously quiet had installed them, turning each individual area on its head. In regions that had been noisy but had since quieted down, some trees had made a comeback with fresh seedlings, but some specific species of plants didn’t bounce back as well as others.

It’s believed that the bird species that feed on the various seeds — in the case of the pinyon pine, the California scrub jay is a big seed-spreader — had not returned to the areas for one reason or another. It’s likely, the researchers say, that the jays had associated these areas with loud or even painful noise and even though the areas were now quiet, the birds refused to return.

It’s disheartening to imagine that, because humans are so noisy, we might change entire ecosystems without even realizing it, but that appears to be not just plausible, but likely.

Also see:

Save the Earth: Pray for a Pandemic | Exposing the Big Game (wordpress.com)

New depictions of ancient hominids aim to overcome artistic biases

Reconstructions based on intuition can distort views of what extinct species looked like

a dramatic reconstruction of an ancient hominid face with coarse black hair
New standards for reconstructing extinct hominids could lead to more accurate representations, such as this sculpture of a 2.8-million-year-old Australopithecus africanus youngster known as the Taung child.G. VINAS, R.M. CAMPBELL, M. HENNEBERG AND R. DIOGO

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By Tina Hesman Saey

6 HOURS AGO

Depictions of extinct human ancestors and cousins are often more art than science.

Take, for example, two reconstructions of the Taung child, a 2.8-million-year-old Australopithecus africanus skull discovered in South Africa in 1924. One version, made using a sculptor’s intuition, appears more apelike. A second version, made while working alongside a scientist, appears more humanlike.

Now, the researchers that produced the dueling images are attempting to remove some of this subjectivity by introducing standards that may give more accurate and reproducible portraits of species known only from fossilized bone. The team points out some of the flaws in facial reconstructions of ancient hominids — and the social and ethical implications misleading portraits may have — in a report published February 26 in Frontiers in Ecology and Evolution.

side by side computer illustrations of a face and head
These two reconstructions of the Taung child depend on subjective decisions to make it appear more apelike (left) or humanlike (right).G. VINAS, R.M. CAMPBELL, M. HENNEBERG AND R. DIOGO

Getting the depictions right matters, says Rui Diogo, a biological anthropologist at Howard University in Washington, D.C. When museumgoers see artists’ renditions of Neandertals or extinct hominids, visitors often don’t realize how much bias creeps into the work. “They think it is reality,” he says. And that can skew people’s views and reinforce existing prejudices of present-day people.

For instance, reconstructions of multiple extinct hominids in the Smithsonian National Museum of Natural History in Washington, D.C., portray skin getting lighter and lighter in color as species became more and more bipedal. “But there is zero evidence to say the skin was whiter,” Diogo says. Such a depiction might give the mistaken impression that people with lighter skin are more evolved.

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Artists’ depictions can also give erroneous views of human evolution and extinct species’ intelligence and behavior, says Diogo’s coauthor Ryan Campbell, an anatomical scientist and physical anthropologist at the University of Adelaide in Australia. For instance, Neandertals are often portrayed as having matted, dirty hair. “It’s as if there is a bias toward portraying our ancestors as if they were stupid and didn’t have hygiene,” he says.

But animals of all kinds groom themselves, and there is no reason to think that Neandertals or other extinct hominids were any different. In fact, presenting reconstructions without hair might be more accurate, says Campbell. Hair is usually not preserved in fossils and DNA data from bones may hint at hair color, but don’t reveal grooming habits. 

three views of a scan of a skull
Accurate artistic depictions of extinct hominids begin with precise scans of skeletal findings, such as this digital scan of a cast made from the original Taung child skull fossil.G. VINAS, R.M. CAMPBELL, M. HENNEBERG AND R. DIOGO

“Reconstructing hair is not even informed speculation,” Campbell says. “It’s imaginary speculation.”

Scientists and artists often work together to produce reconstructions, but the choices they make may be driven more by whim than science, the researchers contend. By studying muscles in the great apes and other nonhuman primates, Diogo and colleagues have constructed reference databases that scientists might use in reconstructing faces from fossils. Even then, whether a sculptor chooses chimpanzee or human muscles as their starting point can produce very different outcomes.

“The reconstructions of the past, most of them did not have a scientific basis,” Diogo says. “Our goal is to change the methods and to change the biases” to give a more accurate view of human evolution.

An Entire Group of Whales Has Somehow Escaped Human Attention

An Entire Group of Whales Has Somehow Escaped Human Attention (msn.com)

J. B. MacKinnon  7 hrs ago


California parents of 5 killed by falling redwood treePotent cold front crashes east across U.S., with plunging temperatures…

The marine biologist Jay Barlow likes to say that he went looking for the last of the Ice Age mastodons and instead bumped into a unicorn. It’s a land-based metaphor to help us, a landlubbing species, make sense of what he witnessed late last year, though in fact the mystery unfolded entirely out of sight of land.

In 2014, a team of scientists described acoustic recordings taken far off the coast of California that they suspected were the clicks and buzzes of the Perrin’s beaked whale, the mastodon in Barlow’s metaphor. Though they include 23 known species ranging in size from the pygmy beaked whale, which is about as long as a small hatchback, to the Baird’s beaked whale, which can be nearly the scale of a cargo trailer, beaked whales as a group have remained overlooked cousins of the dolphins and great whales to the present day. Perrin’s beaked whales were among the most obscure of the obscure. Known only from a few carcasses washed ashore in California, they had never been documented alive in the wild.

Four years after those first recordings, acoustic data collected during a National Oceanic and Atmospheric Administration survey captured the same noise pattern. This time it was concentrated around a nameless, undersea ridgetop in the open Pacific Ocean—the middle of nowhere, really—located about 350 kilometers south of the United States–Mexico border. “It was really abundant there,” Barlow, who specializes in marine mammals, told me. “We thought, well, this is good news, maybe we found a spot where the density of the Perrin’s beaked whale is high enough that we might actually have a chance to be the first people to see them.”

It took awhile to put together an expedition during a pandemic year. But on November 15, 2020, a search team co-led by Barlow, the U.S. Navy marine researcher Elizabeth Henderson, and Gustavo Cárdenas Hinojosa, a scientist with the agency responsible for protected areas in Mexico, set sail from a port on the Baja Peninsula. They were aboard a sailboat provided and crewed by the Sea Shepherd Conservation Society as part of a research campaign called Operation Divina Guadalupe—a reference to the image of the Virgin Mary that many Mexicans turn to when they need a miracle.

Active surveying for whales began on the second day at sea; the team saw only a few dolphins. By first light on the third day, the boat was floating nearly a kilometer above the flanks of the unnamed submarine peak where NOAA’s recordings had been made. As a general rule, beaked whales are hard to spot: They slip to the surface rather than surge to it, release no “Thar she blows” puff of exhaled mist, and can easily be hidden by waves kicked up from a gentle breeze. This day, however, the sea was so calm that, looking over the rails of the boat, the crew could see their reflections. “Beaked-whale weather,” Barlow said.

The search started at 6 a.m., with the sun still below the horizon. Eight minutes later, three beaked whales surfaced so close that the scientists didn’t even need to lift their binoculars to see them.

If beaked whales can be hard to see, they are even more difficult to identify. Most look like oversize, thuggish dolphins: They’re often described as cigar shaped, but if so, the cigar is a perfecto, thick through the middle and tapering to the tip and tail. They mainly come in muted tones of gray-brown to blue, often with stripes or polka dots. Neither pattern is as charming as it sounds. The stripes are thought to be scars from underwater battles between males. The polka dots are scars left by the cookiecutter shark, a thalassophobia-inducing creature with jaws designed to remove round plugs of flesh. They sometimes punch permanent holes through beaked whales’ fins.

Telling beaked-whale species apart often comes down to the teeth, a task complicated by the fact that, for the most part, beaked whales are toothless. In nearly all cases, only the males have visible teeth, and usually just one on each side of the lower jaw. The position of these teeth is often distinctive, and their form can be, too: Some resemble ginkgo leaves, others the oblong flensing spades used by 19th-century whalers. The tusks of the strap-toothed whale grow up and across the snout, like a bone ribbon that ties the mouth nearly shut. This apparently causes no problems, because beaked whales—keeping it weird—neither bite nor chew their food. They are suction feeders, drinking in their meals rather than eating them, and they’re also teuthivorous, meaning they primarily eat squid. To do so through a narrower mouth opening only makes the process akin to slurping up noodle soup without cutlery.

When the beaked whales surfaced near the Sea Shepherd boat, the scientists scrambled to make observations, take photographs, and deploy acoustic-recording buoys: Beaked whales are notoriously skittish. Yet these whales lingered for more than an hour, seemingly as curious about their visitors as the visitors were about them. A diver even managed to record some underwater video. Ticking through observations of the whales’ size, coloration, and head shape, the team was soon confident that they weren’t looking at any of the area’s better-known species. “We assumed that these would be Perrin’s beaked whale,” Barlow said. They had found the last mastodons, deep in their hidden valley.

A photograph taken by Henderson seemed to clinch the case. Male Perrin’s beaked whales have their teeth near the tip of the beak, or rostrum, and the image appeared to show just that. On closer inspection, however, the “teeth” turned out to be glints of sunshine. When other photos seemed to show teeth near the midpoint of the jaw, the hope that they had seen Perrin’s beaked whales began to slip away.

“I didn’t want to believe it at the time,” Barlow said. They began to compare their images and audio to descriptions of every other species of beaked whale, trying to make a match. At last, another possibility dawned: that what they had witnessed was not the never-before-seen-alive Perrin’s beaked whale, but a new species entirely. In other words, the metaphorical unicorn: a kind of beaked whale—in this case, an animal twice the size of a bottlenose dolphin and as heavy as a plow-pulling horse—that had somehow gone unnoticed, never known to be seen dead or alive by human eyes. “We were all giddy,” Henderson told me. “There might have been some dancing.”

Back onshore, the news was welcomed as a sign that, just possibly, the human race has not yet left its gaudy thumbprint everywhere. The excitement was heightened by the fact that it was the second year in a row that such a “unicorn” had been reported: In 2019, scientists announced that what had always been considered a smaller, darker variety of the Baird’s beaked whale—one of the best known of the little-known family of beaked whales—was in fact a different species hiding in its cousin’s shadow. That such large animals could remain out of sight on a planet teeming with people and our panopticon technologies into the third decade of the 21st century seemed almost beyond belief.

Whales as a whole are apostates. Life on our planet began in the water and moved onto the land, an evolution that is often represented—in graphics that show fish growing legs and ending up as human beings—as progress. Yet the cetaceans, that grouping of creatures that includes whales, dolphins, and porpoises, reversed the trend. They came ashore, took a look around—and returned to the sea, turning their backs on what would become the human dominion.

Beaked whales were the most emphatic about it. If you have never heard of beaked whales before now, rest assured you are not alone. Other cetaceans appear in the Bible, were carved into rock more than 5,000 years ago in Norway, turn up on fourth-century bas-reliefs. I found a single possible reference to a beaked whale in early art: a playful glass sculpture from Greece that depicts a cetacean with a long, birdlike beak but without the tall fin of a dolphin. Coastal cultures have always known about beaked whales, from animals stranded onshore or glimpsed at sea, but such events were probably as uncommon in antiquity as they are today. The most consistent impression the whales have left on humans is that their flesh and blubber make for dubious eating; a 13th-century Icelandic text gives fair warning that the rendered fat “runs right through” not only humans “or any other animal,” but even vessels made of wood or horn.

In 1823, the French zoologist Georges Cuvier examined the skull of an unknown sea creature and concluded that it was the fossilized remains of an extinct cetacean; the Cuvier’s beaked whale is now believed to be the most widespread of the beaked whales, ranging nearly throughout the world’s oceans. The British scientist William Flower, one of the first people who might fairly be described as anything like a beaked-whale expert, had the following to say in 1872: “Their very presence in the ocean seems to pass unnoticed and unsuspected by voyagers, and even by those whose special occupation is the pursuit and capture of various better known and more abundant cetaceans.” In other words, beaked whales have, with few exceptions, remained at such a remove from human existence that we have never made a habit of hunting and killing them.

Much of our knowledge of beaked whales is still emerging from a vast memento mori of bones and tissues gathered from stranded specimens and housed in the world’s museums. Chris Stinson, a curatorial assistant at the Beaty Biodiversity Museum in Vancouver, is a beaked-whale aficionado (“I just like things that nobody knows anything about,” he told me) and once spent 12 days on a whale survey off Canada’s west coast, during which he logged just about every kind of whale out there—except beaked whales. The closest he has come to an encounter with them is still the museum’s collection of skeletal remains.

He pulled out 10 sets of bones for me. Lifting a Hubbs’ beaked whale skull, it was humbling to think that I could dedicate the rest of my life to seeing the species alive in the wild, and would probably fail. (Humankind’s only truly close encounter with living Hubbs’ whales involved two stranded juveniles who were placed in captivity in a California oceanarium 30 years ago; both died in less than a month.) The skull was an awkward armload. Bizarrely, its size, shape, and long, narrow bill brought to mind the head of Big Bird from Sesame Street, but with none of bird-bone’s lightness: It had heft and density. Without Stinson’s help, I would never have guessed where the eye socket was, and would not have been sure which side was up or down.

“You can’t even tell it’s a skull, really,” Stinson said. “Back in 1997, when I first moved to the West Coast, if I had seen one of these washed up on a beach, I would have thought it was some kind of crazy alien.”

Ironically for animals so little known to us, many beaked whales are named after people—white men, to be exact. (One exception is Deraniyagala’s beaked whale, identified in 1963 from a carcass examined by Paul Deraniyagala, director of the national museums of what is now Sri Lanka.) Most of these men likely never saw a beaked whale alive. The first field studies didn’t begin until the late 1980s, when Hal Whitehead of Dalhousie University in Nova Scotia began to make excursions to the Gully, an underwater canyon 200 kilometers off Canada’s east coast, to research a species of beaked whale called the northern bottlenose whale.

The people who first studied beaked whales in the wild tended to share a similar experience: When they first set out, they were warned that their ambitions were hopeless, because the whales are so rarely seen. Diane Claridge is one such pioneer, having studied beaked whales in the Bahamas since 1991. She told me that even now, having discovered that the Bahamas have long-term, largely site-specific populations of Blainville’s beaked whales, and with three decades of accumulated knowledge about how and where to find them, she still only locates them on about 80 percent of field days—and doesn’t even bother to go looking if the ocean isn’t calm. The sightings often come after hours of searching, and then might involve only brief observations before the animals dive.

“Our notes are like, ‘Up. Down. Up. Down,’” Claridge said.

“Our notes say, ‘Went to this location, searched for an hour. Went to this location, searched for an hour,’” added Charlotte Dunn, her colleague at the Bahamas Marine Mammal Research Organization.

“There’s not many people in the world who would want our job,” Claridge said.

Today, thanks to a handful of dedicated researchers around the globe, four species of beaked whale are relatively well studied: the northern bottlenose whale, Baird’s beaked whale, Cuvier’s beaked whale, and Blainville’s beaked whale. That leaves 19 species of beaked whales—again, creatures of a size that would seem tricky to lose track of—that are somewhere between mysteries and total enigmas. If the species spotted by Operation Divina Guadalupe off Baja last year is confirmed to be a new one, the tally will rise to 20.

When the first handbook dedicated exclusively to beaked whales was finally published in 2017, the authors declared them “the least known of all the large animals in the world.” We know more about certain dinosaurs than some living beaked whales. Yet they are out there right now, perfectly familiar to themselves, perhaps rolling at the surface in a gale, or, in the words of one scientist, “singing their clicks and whistles into the abyss.” They have not needed to come from outer space in order to be otherworldly. They’ve only needed a parallel universe: the life aquatic of the deep sea.

Beaked whales are diving whales, or else, as some now say, they are surfacing whales. It’s a matter of emphasis, of orientation. To call them diving whales is to say that they live at the surface and visit the depths. To call them surfacing whales turns the formula around.

There are few signs that beaked whales take pleasure in time spent at the interface between water and air. When at or even near the surface, they are usually dead silent. They don’t hang around for long, either, often only a minute or two before disappearing. Night and day, probably year-round, they are either making deep dives or preparing to do so, a metronomic pattern that suggests they prefer to spend their time in the lightless waters far below, but regrettably need to breathe air to do so.

“They’re just on this really tight cycle,” Dunn said. “It’s like they don’t have any time to do anything else. Work, sleep; work, sleep.”

Dives of 1,500 meters are ordinary. The deepest on official record is nearly 3,000 meters, but only because a plunge measured at 3,568 meters was discounted due to the fact that the whale’s satellite tag had only been pressure tested to three kilometers of depth. Then there’s the fact that submersibles have photographed large gouges in the seafloor that resemble marks made elsewhere by beaked whales, but they run as deep as 4,258 meters below the surface—two and a half miles down. “I don’t know what to think about this, as it’s super deep and seems insane,” said Nicola Quick, who has studied beaked-whale diving as a research scientist with Duke University’s marine lab.

Yet it is in the deep-water “midnight zone” that beaked whales seem to come to life. There, safe from predators like sharks and killer whales, in cold darkness lit only occasionally by the ghostly glow of luminescent sea creatures, they burst into the sounds they use to echolocate their prey. Somewhere beneath the waves, too, is where the behaviors human eyes have never seen—from males slashing each other with their tusks in battles for dominance to couples mating to the basic act of feeding—presumably take place. The beaked whales might even nap as they tumble into the abyss—scientists have no clear sense, really, of how they otherwise fit enough rest into their 24-hour diving cycle.

“They do things they are not supposed to be able to,” says Andreas Fahlman, a research scientist with the Fundación Oceanogràfic in Valencia, Spain. The essence of how beaked whales have escaped our attention is not how deep they dive, but how long they stay down there. People have forever been fascinated by animals that live in water but, like us, must hold their breath when they’re under it. In an early exploration of such creatures’ limits, the American physiologist Laurence Irving once held a muskrat under water for 12 minutes, only to watch it dive again the moment he let it go. (He gave up on a beaver after just six minutes, when it started thrashing.) At the time, Irving was aware of whalers’ reports that northern bottlenose whales could linger underwater for two hours. Such claims sounded apocryphal.

MORE: An Entire Group of Whales Has Somehow Escaped Human Attention (msn.com)

Scientists discover how humans develop larger brains than other apes

https://phys.org/news/2021-03-scientists-humans-larger-brains-apes.html

MARCH 24, 2021

by UK Research and Innovation

Scientists discover how humans develop larger brains than other apes
Human brain organoids grow substantially bigger than gorilla and chimpanzee (left to right). These brain organoids are 5 weeks old. Credit: S.Benito-Kwiecinski/MRC LMB/Cell

A new study is the first to identify how human brains grow much larger, with three times as many neurons, compared with chimpanzee and gorilla brains. The study, led by researchers at the Medical Research Council (MRC) Laboratory of Molecular Biology in Cambridge, UK, identified a key molecular switch that can make ape brain organoids grow more like human organoids, and vice versa.

The study, published in the journal Cell, compared ‘brain organoids’ – 3-D tissues grown from stem cells which model early brain development—that were grown from human, gorilla and chimpanzee stem cells.

Similar to actual brains, the human brain organoids grew a lot larger than the organoids from other apes.

Dr. Madeline Lancaster, from the MRC Laboratory of Molecular Biology, who led the study, said: “This provides some of the first insight into what is different about the developing human brain that sets us apart from our closest living relatives, the other great apes. The most striking difference between us and other apes is just how incredibly big our brains are.”

During the early stages of brain development, neurons are made by stem cells called neural progenitors. These progenitor cells initially have a cylindrical shape that makes it easy for them to split into identical daughter cells with the same shape.

The more times the neural progenitor cells multiply at this stage, the more neurons there will be later.

As the cells mature and slow their multiplication, they elongate, forming a shape like a stretched ice-cream cone.

Previously, research in mice had shown that their neural progenitor cells mature into a conical shape and slow their multiplication within hours.

Now, brain organoids have allowed researchers to uncover how this development happens in humans, gorillas and chimpanzees.

They found that in gorillas and chimpanzees this transition takes a long time, occurring over approximately five days.

Scientists discover how humans develop larger brains than other apes
After only 5 days, gorilla neural progenitor cells have matured into a conical shape (right), while human cells (left) remain cylindrical. Credit: S.Benito-Kwiecinski/MRC LMB/Cell

Human progenitors were even more delayed in this transition, taking around seven days. The human progenitor cells maintained their cylinder-like shape for longer than other apes and during this time they split more frequently, producing more cells.https://googleads.g.doubleclick.net/pagead/ads?client=ca-pub-0536483524803400&output=html&h=280&slotname=5350699939&adk=3784993980&adf=1857921027&pi=t.ma~as.5350699939&w=753&fwrn=4&fwrnh=100&lmt=1616608675&rafmt=1&psa=1&format=753×280&url=https%3A%2F%2Fphys.org%2Fnews%2F2021-03-scientists-humans-larger-brains-apes.html&flash=0&fwr=0&rpe=1&resp_fmts=3&wgl=1&uach=WyJXaW5kb3dzIiwiMTAuMCIsIng4NiIsIiIsIjg5LjAuNDM4OS45MCIsW11d&dt=1616607687425&bpp=117&bdt=2441&idt=771&shv=r20210322&cbv=r20190131&ptt=9&saldr=aa&abxe=1&cookie=ID%3D5d55f89f953c9743-22b6644a08c70033%3AT%3D1616607686%3ART%3D1616607686%3AS%3DALNI_MYBzRhJl1pJ2SevpeFZZcqkW-bxAA&prev_fmts=0x0&nras=1&correlator=1374116295303&frm=20&pv=1&ga_vid=185394846.1565457508&ga_sid=1616607688&ga_hid=522824615&ga_fc=0&u_tz=-420&u_his=1&u_java=0&u_h=640&u_w=1139&u_ah=607&u_aw=1139&u_cd=24&u_nplug=3&u_nmime=4&adx=263&ady=2425&biw=1123&bih=538&scr_x=0&scr_y=300&eid=44731609%2C21066435%2C21068083%2C44738185%2C44739387&oid=2&pvsid=839096735404007&pem=466&ref=https%3A%2F%2Fnews.google.com%2F&rx=0&eae=0&fc=896&brdim=0%2C0%2C0%2C0%2C1139%2C0%2C1139%2C607%2C1139%2C537&vis=1&rsz=%7C%7CpEebr%7C&abl=CS&pfx=0&fu=8320&bc=31&ifi=1&uci=a!1&btvi=1&fsb=1&xpc=ZHEPBo0JgA&p=https%3A//phys.org&dtd=M

This difference in the speed of transition from neural progenitors to neurons means that the human cells have more time to multiply. This could be largely responsible for the approximately three-fold greater number of neurons in human brains compared with gorilla or chimpanzee brains.

Dr. Lancaster said: “We have found that a delayed change in the shape of cells in the early brain is enough to change the course of development, helping determine the numbers of neurons that are made.

“It’s remarkable that a relatively simple evolutionary change in cell shape could have major consequences in brain evolution. I feel like we’ve really learnt something fundamental about the questions I’ve been interested in for as long as I can remember—what makes us human.”

To uncover the genetic mechanism driving these differences, the researchers compared gene expression—which genes are turned on and off—in the human brain organoids versus the other apes.

They identified differences in a gene called ‘ZEB2’, which was turned on sooner in gorilla brain organoids than in the human organoids.

To test the effects of the gene in gorilla progenitor cells, they delayed the effects of ZEB2. This slowed the maturation of the progenitor cells, making the gorilla brain organoids develop more similarly to human—slower and larger.

Conversely, turning on the ZEB2 gene sooner in human progenitor cells promoted premature transition in human organoids, so that they developed more like ape organoids.

The researchers note that organoids are a model and, like all models, do not to fully replicate real brains, especially mature brain function. But for fundamental questions about our evolution, these brain tissues in a dish provide an unprecedented view into key stages of brain development that would be impossible to study otherwise.

Dr. Lancaster was part of the team that created the first brain organoids in 2013.


Explore further‘Mini brain’ organoids grown in lab mature much like infant brains

Some Generous Apes May Help Explain The Evolution Of Human Kindness

March 20, 20217:15 AM ET

https://www.npr.org/sections/goatsandsoda/2021/03/20/978868116/some-generous-apes-may-help-explain-the-evolution-of-human-kindness

JON HAMILTON

Esake, photographed at the Lola ya Bonobo sanctuary in the Democratic Republic of the Congo in 2019, was rescued from a hunter who killed her mom.Ley Uwera for NPR

It’s feeding time at Lola ya Bonobo, a sanctuary for bonobos in the Democratic Republic of the Congo.

Allez,” caretaker Bernard Nsangu shouts in French as he gets ready to distribute a morning snack. The air fills with piercing shrieks as bonobos nearby tell their friends in the forest that pineapple is coming.

Soon, more than a dozen bonobos have assembled near the grassy perimeter of their enclosure.

With chimpanzees, the prospect of food can lead to aggression.

But bonobos take a different approach, says Suzy Kwetuenda, a biologist at Lola, for whom English is a third language.”As you see, there is many action of sex, many negotiation,” she tells me. “So that make peace.”

This sort of harmony is why, for more than a decade, scientists from around the world have been coming to this sanctuary just outside Kinshasa, along the banks of the Lukaya River. The researchers think bonobos may help explain how humans evolved the capacity to be nice – at least some of the time.

Same genes, different behavior

Bonobos look like smallish chimpanzees, with whom they share 99.6% of their DNA. And both of these great apes share 98.7% of their DNA with humans, making them our closest living relatives.Article continues after sponsor message

What intrigues scientists is that bonobos and chimps often behave very differently, despite their genetic similarity. What’s more, human behavior seems to incorporate aspects of both species.

For example, chimps tend to rely on cunning and competition, while bonobos emphasize cooperation and sharing. The two species also diverge when it comes to leadership, says Dr. Jonas Mukamba, the head veterinarian at Lola.

Bonobos willingly share their food with strangers and value cooperation among members of their group.Ley Uwera for NPR

Chez bonobo,” he tells me, “it is the females who dominate and it is a female who is chief of the group.”

That’s one reason meals at Lola ya Bonobo are so peaceful, Kwetuenda tells me as we watch a group of bonobos gather for what will soon turn into a sort of polyamorous picnic.

She points to the alpha female. “This is Semendua, big mom, tough mom,” she says. “And as you can see she is in the front just to show that she is very concerned by all organization in the group.”

Semendua is smaller than many of the males around her. But if a male were to become aggressive, all the females would rally around her to chase him into the forest.

Sharing with strangers

One way that bonobos differ from other great apes is in their eagerness to share, something that has been documented in a series of experiments here at Lola.

The experiments were carried out by a team that included Kwetuenda and Brian Hare, a professor of evolutionary anthropology at Duke University. They were done in Lola’s “bonobo lab,” a building that features room-size cages and a place for scientists to observe what happens inside them.

In one experiment, the scientists put two bonobos in adjacent rooms. Then they gave one of the animals a plate of prized food, like bananas or apples, which have to be imported. The fruit plate was topped with a type of cream Kwetuenda calls “bonobo sauce.”

The bonobo with food was given a choice: eat alone, or use a special key to let in their neighbor.

“In our mind, we thought that because of nice food they would first eat,” Kwetuenda says. “But we were surprised to see that roommate is more important than favorite food.”

Later, the scientists repeated the experiment with three bonobos, one of whom was a stranger. This time, the bonobo with food usually shared with the stranger first, then invited the friend to join in.

Bonobos avoid confrontation and promote cooperation, often through sex.Ley Uwera for NPR

In another study, scientists showed that bonobos are willing to help one another obtain food even if they know they won’t get to share it. This generosity with food does not extend to tools, though.

Apparently selfless behavior may seem odd from an evolutionary perspective. But scientists believe it paved the way to the sort of large-scale cooperation that has helped Homo sapiens outlast other early humans, like Homo erectus. And this sort of cooperation has allowed our species to share new ideas, create vast nations and explore other planets.

A lab in the forest

Research at Lola ya Bonobo has produced more than 75 published studies. Scientists keep returning because the DRC is the only place on earth where these animals still live in the wild, and this sanctuary provides a unique place to study their behavior in a naturalistic setting.

Lola was founded nearly 30 years ago by Claudine André, a Belgian whose father was a veterinarian in Kinshasa. In 1991, while working at the Kinshasa Zoo, André looked into the eyes of a bonobo and, she says, “fell in love with this species.”

After Lola moved into its current home (once a summer residence for former president Mobutu Sese Seko), André began hosting scientists from countries including the U.S., Japan and Germany. Over the years, scientific research has been able to document many of the bonobo behaviors that André and the Lola staff see every day.

A trio of young bonobos play under the watchful eyes of their caregivers.Ley Uwera for NPR

For example, André has often said that bonobos are “full of empathy.” And sure enough, an Italian team found that if one bonobo yawns, others will yawn too — a behavior closely associated with empathy.

Research also support André’s belief that bonobos have a keen understanding of what’s going on in another individual’s mind, and when that individual wants to help them.

SHOTS – HEALTH NEWS

How Humans Domesticated Themselves

In their book Survival of the Friendliest, published in 2020, Brian Hare and Vanessa Woods describe an experiment in which a researcher would hide a treat under one of two upside-down cups. Then they invited several different animal species to figure out which cup hid the treat.

Chimps, despite their cleverness, just kept choosing one of the cups at random. But bonobos (and dogs) almost immediately learned to look to the scientist for a gesture indicating the right cup.

One study even found a structural difference between the brains of bonobos and chimps. The difference involved circuits controlling social and emotional behaviors.

What all the science suggests is that bonobos have evolved in a way that predisposes them to sharing, tolerance, negotiation and cooperation.

Those are all traits you can see in humans, on a good day, André says.

“Humans can be a fantastic bonobo with a big heart or a very dangerous warrior,” she says. “We are mixed.”

Lessons from a close relative

It’s been about 6 million years since the death of the last common ancestor we shared with chimps and bonobos. Since then, we humans have channeled our inner bonobo to share and cooperate on a massive scale.

But we’ve often acted more like chimps — whose murder rate in the wild is comparable to our own — when it comes to behaviors like violence against members of our own species.

Humans do not share bonobos’ assumption that every stranger is a potential friend. Studies show we may not even consider a stranger fully human if they belong to a group perceived as other and threatening.

When that happens, scientists say, we tend to suppress empathy and embrace cruelty.

Human cruelty is something Yvonne Vela Tona, a caretaker at Lola ya Bonobo, has seen up close.

Yvonne Vela Tona, one of the “mamas” at the sanctuary, looks after the young bonobo Esake.Ley Uwera for NPR

Vela Tona fled Angola more than 20 years ago to escape a civil war that would eventually kill more than 500,000 people. Since then, she’s lived in the DRC, a nation where decades of armed conflict has led to millions of deaths.

Vela Tona has raised children of her own and served as a surrogate mother to more than 20 bonobos. She’s seen both the chimp and bonobo sides of human behavior.

What people can learn from bonobos, she tells me through an interpreter, is that war and violence are not inevitable, that we, like bonobos, have the capacity to resolve conflicts through other means.

How early humans’ quest for food stoked the flames of evolution

The Banquet of the Monarchs, c1579, by Alonzo Sanchez Coello
The Banquet of the Monarchs, c1579, by Alonzo Sanchez Coello: ‘high food culture’ in the middle ages. Photograph: Album/Alamy

[The painting with the elephant being burned alive tells the whole story.]

https://www.theguardian.com/science/2021/mar/07/how-early-humans-quest-for-food-stoked-the-flames-of-evolution

A love of complex smells and flavours gave our ancestors an edge and stove pped hangoversDonna FergusonSun 7 Mar 2021 01.16 EST

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Human evolution and exploration of the world were shaped by a hunger for tasty food – “a quest for deliciousness” – according to two leading academics.

Ancient humans who had the ability to smell and desire more complex aromas, and enjoy food and drink with a sour taste, gained evolutionary advantages over their less-discerning rivals, argue the authors of a new book about the part played by flavour in our development.

Some of the most significant inventions early humans made, such as stone tools and the controlled use of fire, were also partly driven by their pursuit of flavour and a preference for food they considered delicious, according to the new hypothesis.Advertisementhttps://5037925012011699e0d1c13b2cbcd914.safeframe.googlesyndication.com/safeframe/1-0-37/html/container.html

“This key moment when we decide whether or not to use fire has, at its core, just the tastiness of food and the pleasure it provides. That is the moment in which our ancestors confront a choice between cooking things and not cooking things,” said Rob Dunn, a professor of applied ecology at North Carolina State University. “And they chose flavour.”

Cooked food tasted more delicious than uncooked food – and that’s why we opted to continue cooking it, he says: not just because, as academics have argued, cooked roots and meat were easier and safer to digest, and rewarded us with more calories.

Some scientists think the controlled use of fire, which was probably adopted a million years ago, was central to human evolution and helped us to evolve bigger brains.

“Having a big brain becomes less costly when you free up more calories from your food by cooking it,” said Dunn, who co-wrote Delicious: The Evolution of Flavour and How it Made Us Human with Monica Sanchez, a medical anthropologist.Advertisementhttps://5037925012011699e0d1c13b2cbcd914.safeframe.googlesyndication.com/safeframe/1-0-37/html/container.html

However, accessing more calories was not the primary reason our ancestors decided to cook food. “Scientists often focus on what the eventual benefit is, rather than the immediate mechanism that allowed our ancestors to make the choice. We made the choice because of deliciousness. And then the eventual benefit was more calories and fewer pathogens.”

Human ancestors who preferred the taste of cooked meat over raw meat began to enjoy an evolutionary advantage over others. “In general, flavour rewards us for eating the things we’ve needed to eat in the past,” said Dunn.

In particular, people who evolved a preference for complex aromas are likely to have developed an evolutionary advantage, because the smell of cooked meat, for example, is much more complex than that of raw meat. “Meat goes from having tens of aromas to having hundreds of different aroma compounds,” said Dunn.

Prehistoric woolly mammoth hunters
Prehistoric woolly mammoth hunters. Photograph: North Wind Picture Archives/Alamy

This predilection for more complex aromas made early humans more likely to turn their noses up at old, rotten meat, which often has “really simple smells”. “They would have been less likely to eat that food,” said Dunn. “Retronasal olfaction is a super-important part of our flavour system.”

The legacy of humanity’s remarkable preference for food which has a multitude of aroma compounds is reflected in “high food culture” today, Dunn says. “It’s a food culture that really caters for our ability to appreciate these complexities of aroma. We’ve made this very expensive kind of cuisine that somehow fits into our ancient sensory ability.”Advertisement

Similarly, our proclivity for sour-tasting food and fermented beverages like beer and wine may stem from the evolutionary advantage that eating sour food and drink gave our ancestors.

“Most mammals have sour taste receptors,” said Dunn. “But in almost all of them, with very few exceptions, the sour taste is aversive – so most primates and other mammals, in general, will, if they taste something sour, spit it out. They don’t like it.”

Humans are among the few species that like sour, he says, another notable exception being pigs.

At some point, he thinks, humans’ and pigs’ sour taste receptors evolved to reward them if they found and ate decomposing food that tasted sour, especially if it also tasted a little sweet – because that is how acidic bacteria tastes. And that, in turn, is a sign that the food is fermenting, not putrefying.

“The acid produced by the bacteria kills off the pathogens in the rotten food. So we think that the sour taste on our tongue, and the way we appreciate it, actually may have served our ancestors as a kind of pH strip to know which of these fermented foods was safe,” said Dunn.

Human ancestors who were able to accurately identify rotting food that was actually fermenting, and therefore OK to eat, would have had an evolutionary advantage over others, he argues. If they also figured out how to safely ferment food to eat over winter, they further increased their food supply.

The negative consequence of this is that fermented, alcoholic fruit juice, a sort of “proto wine”, would also have tasted good – and that probably led to horrific hangovers.

“At some point, our ancestors evolved a version of the gene that produces the enzyme that breaks down alcohol in our bodies, which is 40 times faster than that of other primates,” added Dunn. “And so that really made our ancestors much more able to get the calories out of these fermented drinks, and it would also probably have lessened the extent to which they had hangovers every day from drinking.”Advertisementhttps://5037925012011699e0d1c13b2cbcd914.safeframe.googlesyndication.com/safeframe/1-0-37/html/container.html

Flavour also drove humanity to innovate and explore, Dunn says. He thinks one reason our ancestors were inspired to begin using tools was to get hold of otherwise inaccessible food that tasted delicious: “If you look at what chimpanzees use tools to get, it’s almost always really delicious things, like honey.”

Having a portfolio of tools that they could use to find tasty things to eatgave our ancestors the confidence to explore new environments, knowing they would be able to find food, whatever the season threw at them. “It really allows our ancestors to move out into the world and do new things.”

Still Life with a Turkey Pie, by Pieter Claesz, 1627.
Still Life with a Turkey Pie, by Pieter Claesz, 1627. Photograph: FineArt/Alamy

Stone tools in particular “fast-forward” the ability of humans to find delicious food. “Once they can hunt, using spears, they have access to this whole world of foods that were not available to them before.”

At this point, Dunn thinks humanity’s pursuit of tasty food started to have terrible consequences for other species. “We know that humans around the world hunted species to extinction, once they figured out how to hunt really effectively.”

Dunn strongly suspects that the mammals that first went extinct were the most delicious ones. “From what we were able to reconstruct, it looks like the mammoths, mastodons and giant sloths all would have been unusually tasty.”Paleolithic diet may not have been that ‘paleo’, scientists sayRead more

To replicate the eating habits of prehistoric humans, the book, published later this month, details how one scientist dropped a horse who had just died into a pond and assessed how it fermented over time. “He would sample some meat to see if it was safe to eat. He described it as delicious – a little bit like a blue cheese,” said Dunn.