Category: Evolution

Biologists Surprised That Marine Animals Are “Having a Blast” in “Great Pacific Garbage Patch”

(p. A3) Biologists who fished toothbrushes, rope and broken bottle shards from the Great Pacific Garbage Patch found them studded with gooseneck barnacles and jet-black sea anemones glistening like buttons. All told, they found 484 marine invertebrates from 46 species clinging to the detritus, they reported Monday [April 17, 2023] in the journal Nature Ecology & Evolution.

. . .

Marine ecologists said they would expect most coastal species to struggle to survive outside their shoreline habitats. On the Great Pacific Garbage Patch, animals were found growing and reproducing.

“They’re having a blast,” said study author Matthias Egger, head of environmental and social affairs at the Dutch nonprofit The Ocean Cleanup. “That’s really a shift in the scientific understanding.”

Anemones like to protect themselves with grains of sand, Dr. Egger said, but out in the garbage patch they are covered in seed-like microplastics. Squeeze an anemone and the shards spew out, he said: “They’re all fully loaded with plastic on the outside and inside.”

. . .

The patch is also a haven for animals that are at home on the open ocean. Such species—sea snails, blue button jellyfish, and a relative called by-the-wind sailors—gather more densely where there is more plastic, Dr. Helm and her team said in a study posted online ahead of peer-review.

Removing the plastic would mean uprooting them, Dr. Helm said: “Cleaning it up is not actually that simple.”

For the full story, see:

Nidhi Subbaraman. “Ocean Garbage Patch Hosts Critters.” The Wall Street Journal (Tuesday, Apr. 18, 2023): A3.

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

(Note: the online version of the story was updated April 17, 2023, and has the title “Pacific Ocean Garbage Patch Is Bursting With Life.” The 7th, 8th, and 9th sentences quoted above, appear in the online, but not in the print, version of the commentary. Also, the online version of the sentence on being able to handle switching, contains seven added words of detail.)

The published version of the “posted online” article mentioned above is:

Haram, Linsey E., James T. Carlton, Luca Centurioni, Henry Choong, Brendan Cornwell, Mary Crowley, Matthias Egger, Jan Hafner, Verena Hormann, Laurent Lebreton, Nikolai Maximenko, Megan McCuller, Cathryn Murray, Jenny Par, Andrey Shcherbina, Cynthia Wright, and Gregory M. Ruiz. “Extent and Reproduction of Coastal Species on Plastic Debris in the North Pacific Subtropical Gyre.” Nature Ecology & Evolution 7, no. 5 (April 17, 2023): 687-97.

Global Warming Can Allow a “Sudden Efflorescence” of Adaptation from Dormant “Sleeping Beauties”

Above the title of the book review quoted below, the Wall Street Journal printed a few lines from a poem by Baudelaire:

Many a jewel of untold worth
Lies slumbering at the core of Earth
In darkness and oblivion drowned . . .
–Charles Baudelaire, “Le Guignon”

(p. C12) In his new book, Mr. [Andreas] Wagner, a professor at the Department of Evolutionary Biology and Environmental Studies at the University of Zurich, showcases biological “sleeping beauties”: animals, plants, even bacteria that for generations plugged along with modest evolutionary success, only to later flourish spectacularly. “Sleeping Beauties: The Mystery of Dormant Innovations in Nature and Culture” explains how evolutionary adaptations sometimes go from dormancy to full flowering, while also suggesting that an analogous process applies to human innovations, including science, technology and the arts.

. . .

First we need to recall that not every biological trait an organism possesses is optimal for its current environment. The swim bladder, for example, evolved in fish as an aid to adjusting buoyancy, only later becoming the basis for lungs when their descendants became terrestrial. And the human appendix currently appears to be more an evolutionary liability than an asset, although it may well have conveyed immunologic benefits in the past—and could even prove adaptive in the future. Certain traits may develop that are not immediately adaptive, in the sense of contributing directly to the reproductive success of the genes responsible for the trait and of the individuals carrying them.

If an organism develops a characteristic maladapted to its environment, it and the genes responsible for the trait are selected away into oblivion. But if the novelty is not particularly harmful, or even somewhat helpful, the trait may simply hang around through the generations—until a descendant organism finds a welcoming environmental niche.

The natural world is filled with solutions awaiting a problem.  . . .  But when environments change (and they always do), a wonderful and lively explosion can ensue.

Mr. Wagner refers to this sudden efflorescence as “adaptive radiation”—“only with a key innovation,” he writes, “can a species exploit existing opportunities, such as a warmer climate, a new source of food, or a superior form of shelter. In this view, any one adaptive radiation has to wait, possibly for a long time, until the right innovation arises. And the need to wait holds evolution back.”

In regard to evolutionary developments that at first seem to bear no fruit, Mr. Wagner could have quoted from Thomas Gray’s “Elegy Written in a Country Churchyard”:

Full many a gem of purest ray serene,
The dark unfathom’d caves of ocean bear:
Full many a flow’r is born to blush unseen,
And waste its sweetness on the desert air.

In the world of human creativity, “full many” a terrific creation has been neglected or ignored in its time.

For the full review, see:

David P. Barash. “In Praise of Late Bloomers.” The Wall Street Journal (Saturday, April 29, 2023): C12.

(Note: ellipses, and bracketed name, added, except for first one at the end of quoted passage from Baudelaire.)

(Note: the online version of the review has the date April 28, 2023, and has the title “‘Sleeping Beauties’ Review: Nature’s Late Bloomers.”)

The book under review is:

Wagner, Andreas. Sleeping Beauties: The Mystery of Dormant Innovations in Nature and Culture. London: Oneworld Publications, 2023.

“Unexpected” New Evidence of the Ubiquity and Resilience of Life on Earth

(p. D3) Off the western shores of Central and South America, there is a Lovecraftian, lava-licked realm thousands of feet beneath the ocean. There, on the seafloor, volcanically powered exhaust ports known as hydrothermal vents fire off jets of water that reach temperatures of up to 700 degrees Fahrenheit. While the surfaces and peripheries of these vents have long been known to host a diverse mosaic of life, scientists had never known animals to find a home beneath these hellish geysers.

But that changed in July [2023] when a diving robot overturned volcanic bedrock pockmarked with hydrothermal vents and revealed an explosion of animal life — including an abundance of tubeworms, bizarre creatures that resemble sentient spaghetti.

“This is the first time that animal life was found below the surface” of hydrothermal vents, said Monika Bright, an ecologist at the University of Vienna and lead scientist on the expedition.

. . .

Much about these unusual habitats is a mystery. But, like many revelations found at the bottom of the sea, this discovery once again pushes the boundaries of what scientists consider possible — perhaps even normal — for life on Earth.

Hydrothermal vents, first discovered off the Galápagos Islands, are Dalí-esque chimneys and chasms that often grow atop or close to midoceanic ridges — vast volcanic fissures in the seafloor made by the divergence of two tectonic plates. Deep below, the magmatic heat roasts percolating seawater, which jets back out into the water column as superheated, mineral-rich soups.

Despite their extreme natures, these vents are metropolises of strange critters. Common among them are tubeworms, which start life as free-swimming larvae before becoming immobile adults that grow to several feet in length and that are fed by sulfur-eating bacteria living in their guts.

Dr. Bright suspected that these wiggly weirdos could also be found beneath the vents. “It’s kind of a really crazy idea I had,” she said.

. . .

. . . for Dr. Bright, Earth is all that matters. “I’m not thinking of other planets and moons — I’m thinking that there’s so much mystery to be discovered in our Earth,” she said. “I feel like I know this place. I’ve studied this place for 30 years. And still, you can find something unexpected.”

For the full story, see:

Robin George Andrews. “Odd Creatures Found Under Oceanic Vents.” The New York Times (Tuesday, August 15, 2023): D3.

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

(Note: the online version of the story has the date Aug. 8, 2023, and has the title “Under a Hellish Ocean Habitat, Bizarre Animals Are Lurking.”)

Small-Brained Early Humans Buried Their Dead and Used Symbols

(p. A16) Discoveries from a subterranean cave system in South Africa are prompting paleoanthropologists to rethink what makes us human. New findings reveal a small-brained human relative known as Homo naledi buried its dead and carved symbols on walls inside the system. Both these behaviors were previously associated with our species or the big-brained Neanderthals with which we interbred.

“We’re looking at cultural behavior that is very human in a species that has a brain a third the size of ours,” said John Hawks, a University of Wisconsin-Madison paleoanthropologist and co-author of the research released Monday [June 5, 2023], which will soon be published in the journal eLife as reviewed preprints. “It is going against the idea that brain size is what made us human.”

. . .

“We’ve never had a creature that manifested the complexity of us that wasn’t us,” said Lee Berger, a paleoanthropologist and an explorer in residence at National Geographic who co-authored the new research. Homo naledi, he added, is “threatening to the very clearly defined narrative of the rise of human exceptionalism.”

For the full story, see:

Aylin Woodward. “Ape-Size-Brained Relative Upends Theories.” The Wall Street Journal (Tuesday, June 6, 2023): A16.

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

(Note: the online version of the story was updated June 5, 2023, and has the title “New Homo Naledi Cave Discoveries Upend What We Know About Being Human.”)

The reference to the journal preprint mentioned above is:

Agustin, Fuentes, Kissel Marc, Spikins Penny, Molopyane Keneiloe, Hawks John, and R. Berger Lee. “Burials and Engravings in a Small-Brained Hominin, Homo Naledi, from the Late Pleistocene: Contexts and Evolutionary Implications.” bioRxiv (2023): 2023.06.01.543135.

As Worms Return to Arctic, Some Life Forms Will Thrive and Others Will Not

(p. A1) Worms are on the move, and people are nervous.

That’s because they’re taking over territory in the Far North that’s been wormless since the last ice age.

. . .

Because of changes in the chemistry and physics of the ground, grasses and shrubby plants tend to thrive, taking over from tundra mosses and lichens. That’s good news for the lemmings and voles that favor such plants, according to Hanna Jonsson, an ecology researcher at Umea University. But probably not good for other herbivores that might not adapt easily to a change in available food.

For the full story, see:

Sofia Quaglia. “Worms Haven’t Lived in the Arctic Since the Last Ice Age. But Now, They’re Back.” The New York Times (Saturday, July 15, 2023): A10.

(Note: ellipsis added.)

(Note: the online version of the story has the date July 14, 2023, and has the title “Some Squirmy Stowaways Got to the Arctic. And They Like It There.”)

Homo Sapiens’s Greater Genetic Diversity May Have Allowed Them to Adapt to Climate Change Faster than Neanderthals

(p. D5) Scientists have revealed a surprisingly complex origin of our species, rejecting the long-held argument that modern humans arose from one place in Africa during one period in time.

By analyzing the genomes of 290 living people, researchers concluded that modern humans descended from at least two populations that coexisted in Africa for a million years before merging in several independent events across the continent. The findings were published on Wednesday [May 24, 2023} in Nature.

“There is no single birthplace,” said Eleanor Scerri, an evolutionary archaeologist at the Max Planck Institute for Geoarchaeology in Jena, Germany, who was not involved in the new study. “It really puts a nail in the coffin of that idea.”

. . .

The researchers concluded that as far back as a million years ago, the ancestors of our species existed in two distinct populations. Dr. Henn and her colleagues call them Stem1 and Stem2.

About 600,000 years ago, a small group of humans budded off from Stem1 and went on to become the Neanderthals. But Stem1 endured in Africa for hundreds of thousands of years after that, as did Stem2.

If Stem1 and Stem2 had been entirely separate from each other, they would have accumulated a large number of distinct mutations in their DNA. Instead, Dr. Henn and her colleagues found that they had remained only moderately different — about as distinct as living Europeans and West Africans are today. The scientists concluded that people had moved between Stem1 and Stem2, pairing off to have children and mixing their DNA.

. . .

It’s possible that climate upheavals forced Stem1 and Stem2 people into the same regions, leading them to merge into single groups. Some bands of hunter-gatherers may have had to retreat from the coast as sea levels rose, for example. Some regions of Africa became arid, potentially sending people in search of new homes.

Even after these mergers 120,000 years ago, people with solely Stem1 or solely Stem2 ancestry appear to have survived. The DNA of the Mende people showed that their ancestors had interbred with Stem2 people just 25,000 years ago. “It does suggest to me that Stem2 was somewhere around West Africa,” Dr. Henn said.

. . .

Dr. Scerri speculated that living in a network of mingling populations across Africa might have allowed modern humans to survive while Neanderthals became extinct. In that arrangement, our ancestors could hold onto more genetic diversity, which in turn might have helped them endure shifts in the climate, or even evolve new adaptations.

“This diversity at the root of our species may have been ultimately the key to our success,” Dr. Scerri said.

For the full story, see:

Carl Zimmer. “A Study’s New Twist on How the First Humans Evolved.” The New York Times (Tuesday, May 30, 2023): D5.

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

(Note: the online version of the story was updated May 24, 2023, and has the title “Study Offers New Twist in How the First Humans Evolved.”)

The article in Nature mentioned above is:

Ragsdale, Aaron P., Timothy D. Weaver, Elizabeth G. Atkinson, Eileen G. Hoal, Marlo Möller, Brenna M. Henn, and Simon Gravel. “A Weakly Structured Stem for Human Origins in Africa.” Nature 617, no. 7962 (May 25, 2023): 755-63.

Growing Research Suggests Neanderthals Were More Similar to Homo Sapiens in Behavior

(p. A16) Neanderthals might be getting a bad rap. In the movie “Night at the Museum,” when the exhibits come to life after sundown, the Neanderthals are depicted as dimwitted cave men who grunt and bash rocks together in futile attempts to generate a flame. When Ben Stiller’s night-guard character gives them a lighter, one promptly sets himself on fire.

Popular culture has often depicted our Neanderthal cousins much like these museum cave men—also-rans and unsophisticated brutes whose nomadic-hunter lifestyle precluded them from social gatherings and might have contributed to their demise.

But the past decade or so has changed our understanding of Neanderthals. A growing body of research shows these extinct relatives—who overlapped in time and space with anatomically modern humans, or Homo sapiens—were similar to us in many ways. Recent studies suggest Neanderthals altered the landscape around them with fire and were sophisticated hunters who could exploit a variety of prey in groups larger than paleoanthropologists once thought.

Studies show the species used fire to cook, constructed tools to manipulate meat and stone, built structures and made jewelry. They swam and dove for shells, which they used as tools and beads, and distilled birch bark to make tar. Neanderthals decorated and engraved bones and used red ochre—a natural clay pigment—to alter surfaces.

“The more we learn about Neanderthals, the more similar they look to us behaviorally,” said Chris Stringer, research leader in human origins at the Natural History Museum in London.

For the full story, see:

Aylin Woodward. “Scientific Discoveries Elevate the Minds and Skills of Neanderthals.” The Wall Street Journal (Tuesday, April 11, 2023): A16.

(Note: the online version of the story has the date April 10, 2023, and has the title “Neanderthals and Us: We’re More Alike Than Once Thought.” The wording in the last sentence quoted above is from the print version, rather than the shorter online version, of the sentence.)

Marine Life Turns Man-Made Artifacts into a Biodiverse Habitat

(p. 21) Kirstin Meyer-Kaiser, a marine biologist at the Woods Hole Oceanographic Institution, who . . . has studied the connection between underwater sites and marine biodiversity, said that leaving human artifacts in place was also likely better for any marine wildlife. “It was not supposed to be there in the first place,” she said of the relics. “But after a certain amount of time, any man-made object turns into a habitat.”

For the full story, see:

Livia Albeck-Ripka. “Under Sea Off Florida: 1800s Cemetery.” The New York Times, First Section (Sunday, May 7, 2023): A21.

(Note: ellipsis added.)

(Note: the online version of the story was updated May 6, 2023, and has the title “Submerged Island Off Florida Reveals Secret: Civil War-Era Cemetery.” The online version says that the page number of the print version is p. A23. My national edition of the print version is on p. A21.)

“Extinct” Species Found Alive, Hanging Out at a Walmart

The formerly extinct giant lacewing species apparently thrives on smoke from fires. So reducing air pollution in the form of smoke from fires might endanger this species. How is a conscientious environmentalist supposed to handle that?

(p. A1) With the world in lockdown in the fall of 2020, Michael Skvarla, an assistant research professor at Penn State University, turned to his private collection, the two cabinets full of insects he kept at home, to show students how to compare insect characteristics.

He unearthed for the camera-connected microscope a specimen he had found back in 2012 clinging to the outside wall of a Walmart in Fayetteville, Ark., and asked students to examine the characteristics of the antlion, a dragonfly-like predator.

Except that this bug, with its nearly two-inch wingspan, was way too big to be an antlion.

“It didn’t have clubbed antennae like it should. It didn’t have lots of cross-veins in the wing like it should,” Dr. Skvarla recalled in an interview.

“So the immediate question was: What is this thing?”

Dr. Skvarla and his students compared features, quickly concluding, live on Zoom, that it was another species that was thought extinct in eastern North America.

The giant lacewing, or Polystoechotes punctata, is a large insect from the Jurassic Era. It was once widespread, but mysteriously disappeared from eastern North America sometime in the 1950s.

The specimen found at the Walmart represents the first recorded in eastern North America in more than half a century, and the first ever recorded in Arkansas.

In a peer-reviewed study published late last year by the Entomological Society of Washington that has only recently been publicized, Dr. Skvarla and a co-author, J. Ray Fisher of Mississippi State University, speculated that the insect could have disappeared with growing light pollution, too little fire smoke (which historical records suggest they like) and the introduction of non-native predators to the region.

For the full story, see:

Emily Schmall. “Lost Relic Reappears At Walmart.” The New York Times (Saturday, March 4, 2023): A12.

(Note: the online version of the story has the date March 2, 2023, and has the title “‘What Is This Thing?’: How a Jurassic-Era Insect Was Rediscovered in a Walmart.”)

The peer-reviewed study mentioned above is:

Skvarla, Michael J., and J. Ray Fisher. “Rediscovery of Polystoechotes Punctata (Fabricius, 1793) (Neuroptera: Ithonidae) in Eastern North America.” Proceedings of the Entomological Society of Washington 124, no. 2 (April 2022): 332-45.

Long-Distance Trade May Help Explain Why Sapiens Flourished More Than Neanderthals

(p. 47) Sykes explains that Neanderthals were sophisticated and competent human beings who adapted to diverse habitats and climates.

. . .

At the time when they encountered the Neanderthals, Sapiens too lived in small bands, but different Sapiens bands probably cooperated on a regular basis. There is much more evidence for long-distance trade among Sapiens, and spectacular burials like the 32,000-year-old Sunghir graves clearly reflect the combined effort of more than one band.

Large-scale cooperation did not necessarily mean that a horde of 500 Sapiens united to wipe out a band of 20 Neanderthals. Cooperation isn’t just about violence. Sapiens could more easily benefit from the discoveries and inventions of other people. If somebody in a neighboring band discovered a new way to locate beehives, to make a tunic or to heal a wound, such knowledge could spread much more quickly among Sapiens than among Neanderthals. While individual Neanderthals were perhaps as inquisitive, imaginative and creative as individual Sapiens, superior networking enabled Sapiens to swiftly outcompete Neanderthals.

This, however, is largely speculation. We still don’t know enough about the psychology, society and politics of Neanderthals to be sure. Perhaps the most surprising fact in Sykes’s book is that even if we count every bone fragment and every isolated tooth, so far we have found the remains of fewer than 300 Neanderthals.

For the full review, see:

Yuval Noah Harari. “Ancient Cousins.” The New York Times Book Review (Sunday, December 6, 2020): 47.

(Note: ellipsis added.)

(Note: the online version of the review was updated Nov. [sic] 9, 2020, and has the title “At Home With Our Ancient Cousins, the Neanderthals.”)

The book under review is:

Sykes, Rebecca Wragg. Kindred: Neanderthal Life, Love, Death and Art. London: Bloomsbury Sigma, 2020.

New Guineans Bred “Pretty Tasty Bananas Without Formal Knowledge of the Principles of Inheritance and Evolution”

(p. D2) Wild bananas, or Musa acuminata, have flesh packed with seeds that render the fruit almost inedible. Scientists think bananas were domesticated more than 7,000 years ago on the island of New Guinea. Humans on the island at the time bred the plants to produce fruit without being fertilized and to be seedless. They were able to develop pretty tasty bananas without formal knowledge of the principles of inheritance and evolution.

For the full story, see:

Oliver Whang. “Fruitful Research: Yes, We Have Lots of Bananas, but Not the Ones You’re Looking For.” The New York Times (Tuesday, October 25, 2022): D2.

(Note: the online version of the story has the date Oct. 17, 2022, and has the title “The Search Is on for Mysterious Banana Ancestors.”)