Category: Evolution

Many Plants and Animals Quickly Adapt to Global Warming

(p. A15) Amid the ice floes of the Arctic, tiny seabirds called dovekies feed in the plankton-rich waters, a survival strategy that worked well until the pack ice began to dwindle around the islands in Russia’s Franz Josef Land, where the dovekies breed. Like their Arctic neighbors the polar bears, often seen stranded on shrinking icebergs, it appeared that the dovekies faced an existential threat because of climate change. Scientists working in the region predicted that they would have to fly an hour or more to find food.

Instead, data from radio-tagged birds have revealed something entirely different: Faced with the prospect of extinction, the dovekies adapted. They were able to pivot to a new foraging opportunity a five-minute flight away, where water from melting glaciers slams into ocean currents just offshore, making plankton there easy pickings. For now, the dovekie population is thriving, producing just as many healthy chicks as before. Unfortunately, this tactic is not a permanent solution, as Arctic glaciers are dwindling too. But it could buy the birds another century to try to adjust their survival strategy again.

The Franz Josef dovekies remind us that nature is not a passive bystander to climate change. In some surprising cases, new conditions can trigger new behaviors.

. . .

When a group of biologists recently fanned out across the eastern Pacific to study aggression in butterfly fish, they expected to witness the constant territorial skirmishes for which these feisty coral reef dwellers are famous. Then a marine heat wave caused the corals to expel their algae, a damaging process called bleaching that leaves once-colorful reefs ghostly pale and lacking in nutrients for fish.

Suddenly without meals worth fighting for, the butterfly fish changed too. They transformed from aggressors into pacifists almost overnight, becoming docile to save energy and eke out an existence, albeit a subdued one, in a calorie-starved environment. If the corals ever recover, then the fish may regain their previous territorial vigor. If not, then they’ll no longer be famous for defending their food; they’ll be too busy trying to find enough of it.

Butterfly fish and dovekies both employ what biologists call “plasticity,” a natural ability to be flexible.

. . .

Warmer temperatures are forcing conifers to shift northward, while many hardwoods are moving north and west, chasing increases in rainfall. But the direction of these shifts isn’t nearly as surprising as their speed. Red oaks like those at Walden Pond are lumbering north by more than 10 miles every decade, which is nothing next to the 40-mile pace set by honey locusts. Both are shifting considerably faster than the range of the average bird: . . .

. . .

When back-to-back hurricanes Irma and Maria battered the Turks and Caicos Islands in 2017, they flattened buildings, uprooted trees and left the community reeling. They also created a rare scientific opportunity. Surveys of a local species of anole—a distant cousin of iguanas—had just been completed prior to the storms. The researchers had intended to show the effects of predation on the lizards by non-native rats. Instead, they turned their attention to the impact of the hurricanes and immediately repeated their field work. What they found was survival of the fittest in action: Lizards in the post-storm population all had larger toe pads and stronger front legs better suited to gripping trees in high winds. And those traits were being passed on to the next generation.

While scientists expected to eventually see evolution in reaction to extreme weather, many were stunned that it could happen so fast. Understanding how some species adapt in various ways, while others can’t, may help to inform our own responses to climate change. Plasticity may become an unavoidable priority in preparing for a warmer world.

For the full commentary, see:

Thor Hanson. “Some Species Are Changing Along With the Climate.” The Wall Street Journal (Saturday, Sept. 25, 2021): A15.

(Note: ellipses added.)

(Note: the online version of the commentary has the date September 24, 2021, and has the same title as the print version.)

The commentary quoted above is adapted from Hanson’s book:

Hanson, Thor. Hurricane Lizards and Plastic Squid: The Fraught and Fascinating Biology of Climate Change. New York: Basic Books, 2021.

Human Footprints from 23,000 Years Ago Found in New Mexico

(p. A3) At the height of the last Ice Age, generations of children and teenagers ambled barefoot along a muddy lakefront in what is now New Mexico, crossing paths with mammoths, giant ground sloths and an extinct canine species known as dire wolves.

Now, some 23,000 years later, the young people’s fossilized footprints are yielding new insights into when humans first populated the Americas. Unearthed in White Sands National Park by a research team that began its work in 2016, the tracks are about 10,000 years older and about 1,600 miles farther south than any other human footprints known in America, scientists reported Thursday in the journal Science.

“It is, in my view, the first unequivocal evidence of human presence in the Americas” during the last Ice Age, Daniel Odess, chief of science and research at the U.S. National Park Service and a senior author of the report, said of the discovery. “The footprints are inarguably human.”

. . .

In earlier work published in 2018, the scientists described an undated set of fossilized human tracks at the White Sands site that they believe were made by people stalking a giant sloth. The tracks overlapped those of the sloth, suggesting a pursuit.

“We will never see humans interacting with giant sloths, but the footprints are telling us the sloths were scared of humans and the humans were confident,” said Sally Reynolds, a paleontologist at Bournemouth and a member of the research team.

The scientists also uncovered what they believe to be the footprints of a prehistoric woman who traveled for almost a mile with a toddler, sometimes carrying the child and sometimes making the young one walk by her side. It is the longest fossilized human trackway ever discovered, according to their research, which was published in 2018 in the journal Quaternary Science Reviews.

For the full story, see:

Robert Lee Hotz. “Footprints Offer Clues About Earliest Americans.” The Wall Street Journal (Monday, Sept. 24, 2021): A3.

(Note: ellipsis added.)

(Note: the online version of the story has the date September 23, 2021, and has the title “Footprints Yield New Clues About the First Americans.” The last paragraph quoted above appears in the online, but not the print, version.)

If Jony Ive Had Designed a Hand Axe for Steve Jobs 200,000 Years Ago

Photo source: WSJ commentary cited below. (Original source: Metropolitan Museum of Art.)

(p. C14) From the beginning, the purpose of the Masterpiece column has been to highlight artworks of surpassing cultural significance and discuss the particular qualities that make them so. How, then, to explain the intrusion into this august company of a utilitarian object, in this case a biface, or hand axe, dated 700,000-200,000 B.C.?

Behind the creative impulse is the aesthetic sense, the desire to make something beautiful, or at least pleasing to the eye. For almost all of human history, utilitarian objects, by contrast, were all about practicality, crafting something that can get the job done. Never the twain shall meet.

Two factors, though, suggest that here the dividing line might not be crystal clear. The first is the biface’s location, not in a natural history museum where they are usually to be found, but the Metropolitan Museum, a repository of art.

The second is its label. “This is one of the largest and most finely crafted bifaces found in France,” we are told. “Its size and the care with which it was made raise the question of whether it was meant to be a tool, or if it was chiefly valued for its appearance and reserved for a different use.”

. . .

From a broadly rounded bottom the two sides flare out then turn inward, ever so gradually tapering to a rounded point that mirrors the bottom edge in miniature. Its changes in depth are equally subtle and well-calibrated, maintaining a uniform thickness along its length and slowly thinning to a shallow wedge starting about three quarters of the way up.

Then there is the material. Flint comes in many colors. The rich caramel hue of this one, lighter in spots than others, may be what caught the eye of our anonymous artisan in the first place. It has veining, too, which likewise seems to have been an attraction, since its curves are echoed by the adjacent edge of the stone.

For the full commentary, see:

Eric Gibson. “The Dawn of Aesthetics.” The Wall Street Journal (Saturday, July 10, 2021): C14.

(Note: ellipsis added.)

(Note: the online version of the commentary has the date July 9, 2021, and has the same title as the print version.)

Evolution Did Not Design an Optimal Human Body

(p. A15) In Alex Bezzerides’s entertaining “Evolution Gone Wrong: The Curious Reasons Why Our Bodies Work (or Don’t),” the author’s quest is to determine the origins of the “aches and pains of the masses and why they happen”—not the mechanical causes of our maladies but the evolutionary ones.

. . .

. . ., according to Mr. Bezzerides, . . . four million years ago our ancestors transitioned from a fruit- and leaves-based diet to one of grasses and sedges. Their molars ballooned out to gargantuan proportions, which was not at first problematic, since their substantive jaws readily accommodated the newly enlarged teeth. But as humans controlled fire, learned to cook, became cooperative, and developed hunting techniques and an accompanying armamentarium of cutting implements, the requirement for robust dentition diminished. We were nevertheless stuck with the legacy of “a mouth full of large teeth.”

. . .

One requires no better evidence of our design’s lack of metaphysical oversight than the absurd configuration of our esophagus and trachea—so near each other as to invite trouble. A benign creator would surely have designed a respiratory system in a way that did not leave us in perpetual fear of choking. But once again this apparently bizarre arrangement results both from our evolutionary origins—the lungs began as an offshoot of the digestive system—and from the requirement for a descended larynx. This “clunky anatomical fault” may give us a fright every time a “hot dog takes a wrong turn at the intersection,” as Mr. Bezzerides writes, but it also facilitated the origin of human speech.

. . .

. . . , he has provided us with a timely reminder that we, as a species, may be outgrowing our evolutionary history and the biology we are constructed from. The emerging technology of genome writing may offer an opportunity to take human design back to first principles.

For the full review, see:

Adrian Woolfson. “BOOKSHELF; Our Fallible Bodies.” The Wall Street Journal (Tuesday, June 1, 2021): A15.

(Note: ellipses added.)

(Note: the online version of the review has the date May 31, 2021, and has the title “BOOKSHELF; ‘Evolution Gone Wrong’ Review: Our Fallible Bodies.”)

The book under review is:

Bezzerides, Alex. Evolution Gone Wrong: The Curious Reasons Why Our Bodies Work (or Don’t). Toronto, Canada: Hanover Square Press, 2021.

As “Neotenous Apes,” Humans Retain Their “Wandering, Exploratory Inner Child”

(p. C4) Cephalopods are having a moment. An octopus stars in a documentary nominated for an Academy Award (“My Octopus Teacher”). Octos, as scuba-diving philosopher Peter Godfrey Smith calls them, also play a leading role in his marvelous new book “Metazoa,” alongside a supporting cast of corals, sponges, sharks and crabs.

. . .

Smart birds and mammals also keep their neurons in one place—their brains. But octos split them up. They have over 500 million neurons altogether, about as many as dogs. But there are as many neurons altogether in their eight arms as in their heads. The arms seem able to act as independent agents, waving and wandering, exploring and sensing the world around them—even reaching out to the occasional diving philosopher or filmmaker. Mr. Godfrey-Smith’s book has a fascinating discussion of how it must feel to have this sort of split consciousness, nine selves all inhabiting the same body.

I think there might be a link between these two strange facts of octopus life. I’ve previously argued that childhood and intelligence are correlated because of what computer scientists call the “explore-exploit” trade-off: It’s very difficult to design a single system that’s curious and imaginative—that is, good at exploring—and at the same time, efficient and effective—or good at exploiting. Childhood gives animals a chance to explore and learn first; then when they grow up, they can exploit what they’ve learned to get things done.

. . .

Human adults are “neotenous apes,” which means we retain more childhood characteristics than our primate relatives do. We keep our brains in our heads, but neuroscience and everyday experience suggest that we too have divided selves. My grown-up, efficient prefrontal cortex keeps my wandering, exploratory inner child in line. Or tries to, anyway.

For the full commentary, see:

Alison Gopnik. “MIND AND MATTER; The Many Minds of the Octopus.” The Wall Street Journal (Saturday, April 17, 2021): C4.

(Note: ellipses added.)

(Note: the online version of the commentary has the date April 15, 2021, and has the same title as the print version.)

The book discussed in Gopnik’s commentary is:

Godfrey-Smith, Peter. Metazoa: Animal Life and the Birth of the Mind. New York: Farrar, Straus and Giroux, 2020.

An Octopus “Is a Being With Multiple Selves”

(p. 11) What makes this book shimmer and shine is Godfrey-Smith’s exploration of marine life (drawing on his vast and extensive diving knowledge and field experience) to illuminate the ways in which the animal mind works — and the thoughts and experiences that give it shape.

. . .

Godfrey-Smith has an elegant and exacting way of urging along our curiosity by sharing his own questions about animal cognizance and the ability of some animals, like rats and cuttlefish, to “meander, drift off and dream.” But perhaps the most enthralling part of this book is the author’s experiences diving at famous sites now affectionately called Octopolis and Octlantis, just off the coast of eastern Australia where several octopuses live, hunt, fight and make more octopuses.

It’s an experience that demands we consider the very real possibility that an octopus, an animal already regarded as one of the most complex in the animal kingdom, is a being with multiple selves. A breathtaking explanation follows, and it’s one that makes even a cephalopod fan like me swoon over the myriad possibilities for rethinking the mind as a sort of hidden realm for sentience.

Godfrey-Smith declares, “The world is fuller, more replete with experience than many people have countenanced,” . . .

For the full review, see:

Aimee Nezhukumatathil. “Deep Dive.” The New York Times Book Review (Sunday, December 27, 2020 ): 11.

(Note: ellipses added; italics in original.)

(Note: the online version of the review has the date Nov. 12 [sic], 2020, and has the title “Where Does Our Consciousness Overlap With an Octopus’s?”)

The book under review is:

Godfrey-Smith, Peter. Metazoa: Animal Life and the Birth of the Mind. New York: Farrar, Straus and Giroux, 2020.

Ancient “Cousin” to Homo Erectus Adapted to “a Chaotic Climate Shift”

(p. D4) Around two million years ago, this area in South Africa is believed to have undergone a chaotic climate shift. The regional environment transformed from wetter and more lush conditions to drier and more arid ones. In order for a species like P. robustus to survive in such terrain, it probably would have needed to be able to chew on tough plants. But the specimen found in the cave at Drimolen didn’t seem to fit with what some scientists had previously stated about the human cousin.

They labeled the skull DNH 155 and determined that it belonged to a male.

. . .

In addition to being smaller than male P. robustus who lived at Swartkrans, DNH 155’s cranium indicated its chewing muscles were not as strong as theirs. Mr. Martin said the differences suggest DNH 155 and the other P. robustus found at Drimolen were smaller not because they were all female, but rather because they were earlier forms of the species belonging to a different population that hadn’t yet been subjected to the environmental pressures that would favor larger sizes and stronger jaw muscles.

“It basically hasn’t become this massive chewing and grinding machine that it becomes later,” Mr. Martin said.

The change would have been the result of microevolution, or an evolutionary change occurring within a species. Such a morphological change, the scientists said, was likely the result of P. robustus adapting to that changing climate, with members of the species who were able to get enough nutrition from a change in their food supply surviving, and passing their traits to offspring.

For the full story, see:

Nicholas St. Fleur. “How to Adapt: A Skull’s Story.” The New York Times (Tuesday, November 17, 2020): D4.

(Note: ellipsis added.)

(Note: the online version of the story has the date Nov. 9, 2020, and has the title “How a Human Cousin Adapted to a Changing Climate.”)

Resilient Eaten Beetle Persists to the End

(p. D2) It’s a familiar story: Predator hunts prey. Predator catches prey. Predator gulps down prey.

Usually, that’s it. But the water scavenger beetle Regimbartia attenuata says, “Not today.” After getting swallowed by a frog, this plucky little insect can scuttle down the amphibian’s gut and force it to poop — emerging slightly soiled, but very much alive.

For the full story, see:

Katherine J. Wu. “A Beetle Swallowed By a Frog Decides To Do an End Run.” The New York Times (Tuesday, August 11, 2020): D2.

(Note: the online version of the story has the date August 3, 2020, and has the title “There Are Two Ways Out of a Frog. This Beetle Chose the Back Door.”)

The scavenger beetle’s escape is documented in:

Sugiura, Shinji. “Active Escape of Prey from Predator Vent Via the Digestive Tract.” Current Biology 30, no. 15 (2020): 867-68.

Covid-19 More Severe If You Inherited a Neanderthal Gene on Chromosome 3

(p. A6) A stretch of DNA linked to Covid-19 was passed down from Neanderthals 60,000 years ago, according to a new study.

Scientists don’t yet know why this particular segment increases the risk of severe illness from the coronavirus. But the new findings, which were posted online on Friday [July 3, 2020] and have not yet been published in a scientific journal, show how some clues to modern health stem from ancient history.

. . .

Last month, researchers compared people in Italy and Spain who became very sick with Covid-19 to those who had only mild infections. They found two places in the genome associated with a greater risk. One is on Chromosome 9 and includes ABO, a gene that determines blood type. The other is the Neanderthal segment on Chromosome 3.

But these genetic findings are being rapidly updated as more people infected with the coronavirus are studied. Just last week, an international group of scientists called the Covid-19 Host Genetics Initiative released a new set of data downplaying the risk of blood type. “The jury is still out on ABO,” said Mark Daly, a geneticist at Harvard Medical School who is a member of the initiative.

The new data showed an even stronger link between the disease and the Chromosome 3 segment. People who carry two copies of the variant are three times more likely to suffer from severe illness than people who do not.

. . .

(p. A7) Tony Capra, a geneticist at Vanderbilt University who was not involved in the study, thought it was plausible that the Neanderthal chunk of DNA originally provided a benefit — perhaps even against other viruses. “But that was 40,000 years ago, and here we are now,” he said.

It’s possible that an immune response that worked against ancient viruses has ended up overreacting against the new coronavirus. People who develop severe cases of Covid-19 typically do so because their immune systems launch uncontrolled attacks that end up scarring their lungs and causing inflammation.

Dr. Paabo said the DNA segment may account in part for why people of Bangladeshi descent are dying at a high rate of Covid-19 in the United Kingdom.

For the full story, see:

Carl Zimmer. “String of Neanderthal Genes May Increase Risk of Severe Illness.” The New York Times (Monday, July 6, 2020): A6-A7.

(Note: ellipses, and bracketed date, added.)

(Note: the online version of the story was updated July 8, 2020, and has the title “DNA Inherited From Neanderthals May Increase Risk of Covid-19.”)

The unpublished paper, mentioned above, is:

Zeberg, Hugo, and Svante Pääbo. “The Major Genetic Risk Factor for Severe Covid-19 Is Inherited from Neandertals.” bioRxiv (posted July 3, 2020).

Early Tool by Extinct Human Ancestors

(p. D2) What’s so special about a 300,000-year-old stick stuck in the muck?

“It’s a stick, sure,” said Jordi Serangeli, an archaeologist from the University of Tübingen in Germany.

. . .

. . . the short, pointed piece of wood his team found in Schöningen, Germany, in 2016 may be the newest addition to the hunting arsenal used by extinct human ancestors during the Middle Pleistocene.

For the full story, see:

Nicholas St. Fleur. “Haywire Immune Reaction Linked to Most Severe Cases.” The New York Times (Tuesday, April 28, 2020): D2.

(Note: ellipses added.)

(Note: the online version of the story has the date April 22, 2020, and has the title “A Short, Pointy, 300,000-Year-Old Clue to Our Ancestors’ Hunting Prowess.”)

Fossil of Oldest Air-Breathing Animal Found

(p. A3) In a trove of fossils dug up decades ago in Wisconsin, a team of paleontologists say they have discovered the oldest known prehistoric scorpion species—and clues about how early organisms evolved to venture onto land.

The arachnids, which were well-enough preserved that researchers could study their internal anatomy, wandered the rich shallow waters of its ancient habitat. Yet the species had cardiovascular and respiratory systems like modern scorpions that could breathe air, say researchers who described their findings in a paper published Thursday in Nature Scientific Reports.

. . .

The researchers dated the fossils to the Silurian Age, a period in the Paleozoic Era between 443 million and 416 million years ago when shallow waters and abundant sunlight allowed colorful reefs and other ancient life to make their debut.

. . .

Joanna Wolfe, who works in the organismic and evolutionary biology department at Harvard University, said the Wisconsin quarry is famously home to marine fossils, so they are “definitely not fully terrestrial, but they are older than the oldest truly terrestrial body fossil of a millipede-like [organism] 427 million years ago.”

“It’s plausible to me that indeed there was a more complex pattern of evolution where we’re going from water to land and back to water, and that that could’ve happened more than once,” said Dr. Wolfe, who wasn’t involved in the research.

For the full story, see:

Katie Camero. “Scorpions Among Earth’s First Air Breathers.” The Wall Street Journal (Friday, January 17, 2020): A3.

(Note: ellipses added.)

(Note: the online version of the story has the date Jan. 16, 2020, and has the title “Ancient Scorpion Offers Clues to How Animals Moved From Sea to Land.”)