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Michael Douglas, a new resident of southern Maryland, credits genetic testing for helping him find his heritage — and a family he knew very little about.

Douglas, 43, is adopted. He knew his birth mother’s name and had seen a birth certificate stating his birth name: Thomas Michael McCarthy. Over the years, Douglas had tried off and on to find his birth family, mostly by looking for his mother’s name, Deborah Ann McCarthy, in phone books and calling the numbers. “I think I must have broken up a lot of marriages,” he laughs.

His search gained urgency in the last five years as he battled a life-threatening illness. “We planned my funeral three times,” he says. Douglas has a genetic disease called Ehlers-Danlos syndrome, caused by a variant in a gene that helps build the body’s connective tissue. His stretchy skin and hyperflexible joints are characteristic of the disease.

“As a kid, I was always dislocating something,” he says. His blood vessels don’t constrict properly to maintain his blood pressure, so Douglas sometimes faints when he stands up. For five years, he has had a constant migraine. Headaches are typical of about a third of people with Ehlers-Danlos. On top of that, he has B cell lymphoma. “I feel like I have the flu every day,” he says. It was time, he decided, to track down his birth family and learn more about his medical history.

In June 2017, Douglas flew to Ireland on what he calls his “death trip.” He wanted to see the land of his McCarthy ancestors. He chose Fethard, because the walled medieval town has a pub called McCarthy’s. (Douglas learned later that he and the pub owner are related.) His health improved during the visit, which he attributes to Ireland’s cool weather. When he returned to Phoenix, where he and his adopted family lived, he had new resolve to find his birth family.

“That’s it,” he decided. “I need my DNA run to find out who I am.” He sent his DNA to three testing companies: Family Tree DNA, AncestryDNA and MyHeritage. With his results plus sleuthing of genealogical records by some helpful strangers, Douglas found his biological family last November and dove headfirst into a new life.

In February, he moved from Phoenix to Maryland to help care for his biological mother as she recovers from a stroke. The new family dynamic hasn’t been easy, but Douglas has bonded with one of his two biological brothers. “And I have a relationship with my ancestors that I did not know before.” He is pleased to find that he resembles his great-grandfather Thomas Rodda, a bicycle maker. Douglas himself is a Star Wars costume maker.
Adoptees like Douglas and birth parents looking for children they gave up often use commercial DNA tests in hopes of reconnecting, says Drew Smith, a genealogical librarian at the University of South Florida in Tampa. Many states make it difficult for adoptees to get birth certificates or other documents that could help them track down birth families. DNA tests are “an end run around the documentation problem,” Smith says.

But the pool of people looking for their genetic roots is much larger. AncestryDNA, the ancestry testing service with the biggest customer base, has persuaded about 10 million people to take its DNA test. 23andMe, Living DNA, Family Tree DNA, MyHeritage, National Geographic’s Geno 2.0 and others also offer customers a chance to use genetics to connect with living relatives and with families’ pasts. A few companies even give hints about ties that go back to Neandertals (SN: 11/11/17, p. 10). But such testing services may not be able to tell you as much about who you are and where your family came from as they claim.
False precision
I got my DNA tested for this multipart reporting project. My assignment was to investigate the science behind DNA testing (SN: 6/9/18, p. 20), but it was also a welcome excuse to learn more about my family’s history.

I already knew a lot about three branches of my family tree. Based on birth and death records, plus census and other documents, most of my family stems from England and Germany. But I dreamed of connecting to relatives on the Hungarian branch, which I knew less about. So I sent saliva or cheek swabs to a handful of testing companies.

My ethnicity estimates were all over the European map. Generally, estimates are most accurate on the broad continental scale. All of the companies agree that my heritage is overwhelmingly European. But that’s where the consensus ends. Even the companies that limit their estimates to broad swaths of the continent told different stories. National Geographic’s Geno 2.0 says that I am 45 percent Southwestern European. Veritas Genetics puts my Southwestern European heritage at only 4 percent and tells me I’m mostly (91.1 percent) north-central European.

The companies that try to dig down to the country level see their confidence in the results go down, but that doesn’t stop them from making very specific estimates. In most reports, the main results given are at the lower end of the confidence scale. 23andMe, for instance, says it has 50 percent statistical confidence in the ethnicity results.

Along with the wide variations between companies, the estimates often didn’t match what I know about my family tree. 23andMe says I’m 16.6 percent Scandinavian. When I sent raw data from 23andMe to MyHeritage to do its own analysis, that company reported no Scandinavian ancestry in my background; it said I’m 16.9 percent Italian. As far as I know, I have no ancestors from Italy or Scandinavia.

Only 23andMe called out my German heritage, though the company lumped it in with French for a total of 18.8 percent. Hungarian is not specifically identified in any company’s estimates. I can only guess that 23andMe’s 3.9 percent Eastern European and 0.3 percent Balkan findings cover that part of my ancestry. Both 23andMe and AncestryDNA say that I have Ashkenazi Jewish heritage. News to me.

Multiple companies agree that a sizable chunk of my heritage is from the British Isles. But even in that, estimates run from 23andMe’s 26.6 percent British and Irish, to Living DNA’s calculation that 60.3 percent of my DNA comes from Great Britain and Ireland, to MyHeritage’s even higher 78.7 percent.

When I shared these inconsistencies with Deborah Bolnick, an anthropological geneticist at the University of Texas at Austin, I could practically hear her shaking her head over the phone.

“They present these very specific, precise numbers down to the decimal point. But it’s a false precision,” Bolnick says. “The tests that are available may not be as nuanced, sensitive and fine scaled as they are presented.”
Checking references
Ethnicity estimates come from comparing patterns of genetic variants — often called single nucleotide polymorphisms, or SNPs — in your DNA with the SNP patterns of pools of people from particular geographic locations. As a way to confirm that a pool solidly represents a place, companies generally require that the people in these pools, known as the reference populations, have four grandparents who were also born in that location. Many of the companies draw reference population DNA samples from people in large public databases compiled by the 1000 Genomes Project, a catalog of genetic variation of thousands of people around the world, and from other studies. Some companies supplement their databases by testing more people in particular parts of the world. So the mixes in reference populations differ across companies.

Who the companies say you are depends in large part on those reference populations, Bolnick says. For instance, you may carry a pattern of SNPs found in people in both southern France and in Italy. If, by chance, the French people a company sampled had that SNP pattern but none of the Italians in the company’s database did, “they may infer that you have French ancestors and not Italian because of who they do and do not have in their database,” Bolnick explains.

Drilling down to tell customers which country or which part of a country their ancestors called home requires sampling many people in those countries, together with more sophisticated math to detect slight differences in the patterns. By looking at more than SNP patterns, Living DNA provides ethnicity estimates down to subregions of the United Kingdom and Ireland. The company analyzes how different stretches of DNA are connected to each other, says David Nicholson, the company’s cofounder and managing director.

It’s a bit like regional differences in the way people in southwest England assemble scones, cream and jam for cream teas. “In Devon you have a scone, cream and then you have jam,” Nicholson says. “In Cornwall you have a scone, jam, cream, so you have them in a different order. Most DNA tests just tell you that you have a scone, jam and cream so you’re from the U.K.” But because his company looks at the order of the DNA ingredients, Nicholson claims his results can tell customers what part of the British Isles was their ancestral home.
Dividing lines
In reality, what the companies can say with certainty is that you share common DNA patterns with people living in those places today. But your ancestors may not always have lived where their descendants do now, Bolnick says. People move around, which muddies the waters.

For many Americans, some branches of their families may be recent immigrants, while other branches may have deep roots in American soil. Two branches of my family came to Massachusetts and Maryland from England in the 1600s. One branch moved from Germany to Nebraska in the late 1800s, and my Hungarian great-grandparents arrived in 1905.

Most Americans who get tested want to know about family from before the big move to the United States, says human geneticist Joe Pickrell, chief executive of DNA testing company Gencove. But the answer isn’t simple. DNA is a record of thousands of ancestors stretching back deep in time, each from a slightly different place. How companies sort out time and place may produce different ancestry estimates, Pickrell says.
Take a stretch of DNA containing a particular SNP pattern. “Today it may be found in you in the United States and in relatives in England and Germany, but it could be that 500 years ago your shared ancestor lived in Italy,” Bolnick explains. Going further back in time, that stretch of DNA may look like it came from Romania, Mongolia and Siberia. “As people move and the genes that they have move with them, it’s going to change what those geographic ancestries look like,” she says.

Given the timing of my family’s migrations, I would have expected a much bigger percentage of my ethnicity to come from the newer immigrants. I thought my British ancestry would have been diluted after hundreds of years in America, but I guess not.

Further complicating matters, most people think of their ancestry as coming from particular countries, but genetics cuts across and transcends national borders, Bolnick says. In reality, those categories are not genetic, they’re sociopolitical and historic.

Smith, in South Florida, agrees: “From a DNA perspective, it’s hard to tell a French person from a German person.”

Missing groups
And some groups, including aboriginal populations in Australia and big parts of Africa and Asia, are mostly absent from companies’ databases. The same goes for Native Americans, whose samples in public databases are small, and in some cases, were collected by questionable means, says Krystal Tsosie, a geneticist at Vanderbilt University in Nashville.
She’s talking about “vampire projects,” in which geneticists swooped in to draw blood from native people, then disappeared. Some scientists have misused DNA samples taken from members of several indigenous nations, conducting studies the DNA donors didn’t consent to and doing studies that contradicted the groups’ cultural and religious beliefs.

In 2002, the Navajo (Diné) Nation — Tsosie’s tribe — declared a moratorium on genetic research. Recently, tribal members have discussed lifting the moratorium, but for now it remains in place, Tsosie says. “We’ve been, for so long, used as research subjects and not really equitable partners in research,” she says. “We’re still waiting for the conversation to change to allow us to have our interests protected.”

As a result of this mistrust of genetic research, there are not enough people from the 566 federally recognized tribes in the genetic databases to enable customers to learn about their tribal heritage from DNA tests. And even if a DNA test could establish that a person carries DNA inherited from a Native American ancestor, that doesn’t make that person a member of the tribe, Tsosie says. Tribal memberships are based on family and community ties, not DNA.

As a volunteer for the Native American Indian Association of Tennessee, Tsosie gets a lot of questions. People get Native American results and want to know if they can share in gaming profits. “It’s not enough to just call yourself a Native American,” she says. “I tell them, you have to go through the genealogy” and document your ancestry. “Typically, the response is, ‘Oh, that sounds like too much work.’ ”

That response baffles her. “If knowing this Native American past — this part of you — is so important, then undergoing the legwork and documentation should be important,” she says. Equally puzzling is why people base their identities on randomly inherited SNP patterns, she says. “Our character, who we are, who we come from is a complex story of a variety of nonbiological factors. To reduce that to a test kit is actually going to ignore the beauty and complexity that is us.”
Mix and unmatch
When genetic testing customers discover that they don’t share DNA with people they thought were their cousins, assumptions can get dark quickly. Are there secrets in the family tree? Not necessarily.

DNA recombination — a reshuffling of bits of the parents’ chromosomes in the cells that give rise to eggs and sperm — creates new genetic combinations, half of which each parent passes to a child. Siblings will share about 50 percent of their DNA. The recombination means children don’t inherit the exact same mix from their parents (unless the kids are identical twins).

That mixing may lead to distant cousins inheriting completely different genetic legacies from their ancestors. The more distant the connection, the more likely relatives are to have no DNA in common. About 10 percent of third cousins (who share the same great-great-grandparents) and 45 percent of fourth cousins (descendants of the same great-great-great-grandparents) have no DNA in common, says Drew Smith, a genealogical librarian at the University of South Florida in Tampa.

“Don’t get upset if you’ve got a documented third cousin and you don’t share any DNA. It happens,” he says. “On the other hand, if you’ve got a second cousin and you don’t share DNA, there’s a problem.”
Making connections
Some ads for testing companies reinforce the link between DNA and identity. An AncestryDNA ad features Kyle Merker, a real person, who says that he grew up thinking he was of German descent. He even danced in German folk groups and wore lederhosen. Merker’s DNA suggests he’s not German at all, but predominantly Scottish and Irish. He’s swapped his lederhosen for a kilt.

The commercial makes it sound like Merker changed his entire culture because of a DNA test. Dig deeper, though, and you’ll find that he researched his family through newspaper articles and government records. These traditional genealogical resources really told Merker the story of his family, Smith says.

“DNA by itself is rarely of any value,” Smith says. “If you’re really interested in researching your family, there’s much more work to be done.” He likens it to ads from Home Depot or Lowe’s: “They make it look like, ‘Oh my gosh, redoing a room is easy.’ ”

Similarly, to really confirm heritage, people have to follow paper trails composed of birth and death certificates, military forms, immigration records, census rolls, church baptism and marriage records, and more. “DNA is just one more type of record,” Smith says. “You’ve got to pull it all together to build your case.”

Michael Douglas found his Irish roots, but it took more than DNA to untangle his heritage. Douglas learned from a McCarthy lineage group on Family Tree DNA that his Y chromosome suggests he’s a descendent of Donal Gott McCarthy, a 13th century Irish king. “Oh, my god, I’m royalty!” he says. The group helped him trace the McCarthy lineage from the 1200s to 1830s Cork County, Ireland.
AncestryDNA’s and MyHeritage’s DNA and genealogical records allowed Douglas and four people he calls his “ancestry angels” to connect him with his biological family. The angels were four strangers who friended Douglas on Facebook and helped him with his family research, using genetic connections Douglas had rejected because they didn’t have the McCarthy last name. The helpers disappeared once he tracked down his mother.

Not all endings are happy. Smith has seen DNA testing split families. “You may discover things that are surprising or disturbing,” he says. You could find out that your father isn’t your father. Or matching to other relatives could uncover family secrets, such as an aunt who never told her family that she gave up a child for adoption or an uncle who knowingly or unknowingly fathered a child.

“It’s fun to learn more about our ancestors and what our ethnicity is,” Smith says. But, he warns, keep in mind that what you learn “may upend your personal life or the personal lives of members of your family.” Don’t do it if you’re not prepared for the repercussions.

Commercials abound for DNA testing services that will help you learn where your ancestors came from or connect you with relatives. I’ve been interested in my family history for a long time. I knew basically where our roots were: the British Isles, Germany and Hungary. But the ads tempted me to dive deeper.

Previous experience taught me that different genetic testing companies can yield different results (SN: 5/26/18, p. 28). And I knew that a company can match people only to relatives in its customer base, so if I wanted to find as many relatives as possible, I would need to use multiple companies. I sent my DNA to Living DNA, Family Tree DNA, 23andMe and AncestryDNA. I also bought the National Geographic Geno 2.0 app through the company Helix. Helix read, or sequenced, my DNA, then sent the data to National Geographic to analyze.
These companies analyze hundreds of thousands of natural DNA spelling variations called single nucleotide polymorphisms, or SNPs. To estimate ethnic makeup, a company compares your overall SNP pattern with those of people from around the world. SNP matches also help companies see who in their database you’re related to.

Some of the companies also analyze a person’s Y chromosome or mitochondrial DNA. Y chromosome DNA traces a man’s paternal line. In contrast, mitochondrial DNA traces maternal heritage, since people inherit mitochondria, which generate energy for cells, only from their mothers. Neither type of DNA changes that much over time, so those tests usually can’t tell you much about recent ancestors.

Once I sent in DNA samples, my Web-based results arrived in just a few weeks. But my user experience, and results, were quite different for each company.

National Geographic Geno 2.0
At $199.95, National Geographic’s test is the most expensive, yet the least useful. The results are generic, and the ethnicity categories are overly broad. My results say that 45 percent of my heritage came from people living in southwestern Europe 500 to 10,000 years ago. That doesn’t tell me much and doesn’t reflect what I know of my family history.
There’s no relative matching, though Geno 2.0 shows which historical “geniuses” may have shared your mitochondrial or Y chromosome DNA. I don’t know how National Geographic knows about the mitochondria of Petrarch, Copernicus or Abraham Lincoln. So I’m skeptical that I am actually related to those famous figures, even from the distance of 65,000 years, the last time we supposedly had an ancestor in common. The service also calculated the percentage of Neandertal ancestry that I carry. I take geeky pride that 1.5 percent of my DNA comes from Neandertals, topping the 1.3 percent average for Geno 2.0 customers.

Overall, Geno 2.0 has a nice presentation, but I learned more about my family history elsewhere. Since I bought the Geno 2.0 kit as an app through Helix, I don’t know if the kit purchased directly from National Geographic, which is processed by Family Tree DNA, would yield different results.

Living DNA
Another expensive test ($159) came from Living DNA. When I saw the company’s ad claiming to pinpoint exactly where in the British Isles a person’s genetic roots stem from, I decided to give it a go. The company highlights ethnicity on a world map, then lets you zoom in from the continent level. I found that 22.5 percent of my heritage came from Lincolnshire in east-central England. I haven’t yet traced any ancestors to Lincolnshire, but I did find through much genealogical sleuthing that one of my sixth-great-grandfathers came from Aberdeen, Scotland. Living DNA says that 3.1 percent of my DNA is from Aberdeenshire. Written narratives on the website provide a history of each reported region.
Using mitochondrial DNA and, if applicable, Y chromosome DNA, the company can trace your maternal and paternal lines back to human origins in Africa and show where and when your particular line probably branched off the original. My “motherline” probably arose in the Near East 19,000 to 26,000 years ago, Living DNA claims, and my ancestors were some of the first people to enter Europe. In February, the company announced that it would soon launch a relative-matching service for its customers.

I’m not sure the service would be worth the price tag for people whose ancestry doesn’t contain a strong British or Irish tilt, though Living DNA says it is working to improve ethnicity estimates in Germany and elsewhere.

Family Tree DNA
The most no-frills of the bunch is Family Tree DNA. For $79, “autosomal” testing looks for genetic variants on all of the chromosomes except the X and Y sex chromosomes. Y chromosome and mitochondrial DNA analysis costs extra.
Family Tree DNA allows a user to build a family tree, incorporating personal DNA tests and matches from the site’s relative-matching section. I found more than 2,400 potential relatives. A chromosome viewer lets me see exactly which bit of DNA I have in common with any particular relative, or with up to five relatives at a time. That feature also allows users to trace how they inherited DNA from a shared ancestor. But I found this tool difficult to use.

The website offers little explanation of results. For instance, I was excited to see that my DNA was compared with that of ancient Europeans, including Ötzi the Iceman, who lived 5,300 years ago (SN: 9/17/16, p. 9). Family Tree DNA is the only company I tried that incorporates ancient DNA into its results and that feature was what convinced me try this company. I did get a breakdown of how different groups — Stone Age hunter-gatherers, early farmers and “Metal Age Invaders” from the Eurasian steppes — contributed to my DNA. But when I saw Ötzi’s dot on my ancestry map, it wasn’t clear if that meant we share DNA or if the map was merely showing where he lived.

23andMe
23andMe ($99) offers one of the more complete packages of information. Most companies show a map of ethnic heritage. 23andMe does, too, but also presents an interactive diagram of all of a person’s chromosomes, indicating which portions carry a particular ethnic ancestry. Because my parents also did 23andMe, I learned that my dad handed me a tiny bit of chromosome 15 that carries western Asian and northern African heritage. My mom gave me the 0.3 percent of my DNA that comes from the Balkans, in a single chunk on chromosome 7, which makes sense since her grandparents came from Hungary. Playing with the chromosomes is fun. But I question the accuracy of these results (see my related article for more on why ancestry tests may miss the mark).
23andMe presents Neandertal heritage in terms of the number of genetic variants you carry. A family-and-friends scoreboard shows where you stack up. (I top my leaderboard with 296 Neandertal variants, more than what 80 percent of 23andMe customers have.) The report also explains what some of those Neandertal variants do, including ones linked to back hair, straight hair, height and whether you’re likely to sneeze after eating dark chocolate. The company doesn’t test for all possible Neandertal variants, including ones that have been linked to health (SN Online: 10/10/17; SN: 3/5/16, p. 18).

Like Geno 2.0, 23andMe uses mitochondrial and Y chromosome DNA to trace the migration patterns of a person’s ancestors, from Africa to the present day.

Relative matching is both interesting and frustrating. I could see the people I match, how we might be related and compare our chromosomes. But 23andMe doesn’t provide a way to build family trees to further explore these relationships.

AncestryDNA
AncestryDNA ($99) doesn’t give the variety of information other companies do. But it has useful genealogical tools, provided you link your results to a family tree that you can build with help from historical records via a paid subscription to Ancestry.com.
One interesting feature of my heritage report was that it went beyond spots on the map in Europe to also show a region of the United States called “Northeastern States Settlers.” A match to that category tells me that my ancestors who came from Europe probably initially settled in New England or around the Great Lakes. They did. One branch of my family tree set roots in Massachusetts in the 1640s. Using birth, death and immigrant records from Ancestry.com, I could build a timeline to show when and from where individual ancestors immigrated to the United States.

AncestryDNA also matches you with relatives, but you can only see how you’re related to those people if they have also chosen to make family trees.

A feature unique to AncestryDNA is called DNA circles. It shows connections between individuals and family groups who share DNA with you. These circles also contain descendants of your ancestors who you don’t directly share DNA with. Therefore, this feature allows you to extend relative matches beyond what traditional DNA matching can do.

For instance, I am in a family group with my uncle and a cousin. We all share DNA with 24 other descendants of Samuel Pickerill, a drummer during the Revolutionary War. Pickerill has 42 other descendants with whom my family group doesn’t share DNA. Those 42 Pickerill descendants happened to inherit different bits of DNA from Pickerill than my uncle, his cousin and I did. That sometimes happens because of the random nature of the rules of biology and genetics (for more on those rules, check out this video).

Genealogy junkie
Although I’ve always been interested in family history, DNA testing has gotten me hooked on genealogy research.

23andMe and AncestryDNA were the most fun to use. 23andMe can tell me whether a relative is on my mother’s or father’s side of the family. But then I have to go back to AncestryDNA and comb through my family tree to learn how we’re really connected. DNA can kick-start a genealogy hunt, but combing through marriage certificates, military rolls, census records, immigration documents, old photographs and other records — which Ancestry.com can provide — is what really tells me who my ancestors were.

Making day-to-day activities more vigorous for a few minutes — such as briefly stepping up the pace of a walk — could offer people who don’t exercise some of the health benefits that exercisers enjoy.

That’s according to a new study of roughly 25,000 adults who reported no exercise in their free time. Those who incorporated three one- to two-minute bursts of intense activity per day saw a nearly a 40 percent drop in the risk of death from any cause compared with those whose days didn’t include such activity. The risk of death from cancer also fell by nearly 40 percent, and the risk of death from cardiovascular disease dropped almost 50 percent, researchers report online December 8 in Nature Medicine.

In a comparison with around 62,000 people who exercised regularly, including runners, gym-goers and recreational cyclists, the mortality risk reduction was similar.

“This study adds to other literature showing that even short amounts of activity are beneficial,” says Lisa Cadmus-Bertram, a physical activity epidemiologist at the University of Wisconsin–Madison, who was not involved in the research. “So many people are daunted by feeling that they don’t have the time, money, motivation, transportation, etc. to go to a gym regularly or work out for long periods of time,” she says. “The message we can take is that it is absolutely worth doing what you can.”

Emmanuel Stamatakis, an epidemiologist at the University of Sydney, and his colleagues analyzed a subset of records from the UK Biobank, a biomedical database containing health information on half a million people in the United Kingdom. The study’s non-exercising participants — more than half of whom were women and were 62 years old on average — had worn movement-tracking devices for a week.

Over an average seven years of follow-up, for those whose days included three to four bursts of activity, the mortality rate was 4.2 deaths from any cause per 1,000 people for one year. For those with no activity bursts, it was 10.4 deaths per 1,000 people for one year.

The researchers were looking for bursts of vigorous activity that met a definition determined in a laboratory study, including reaching at least 77 percent of maximum heart rate and at least 64 percent of maximum oxygen consumption. In real life, the signs that someone has reached the needed intensity level are “an increase in heart rate and feeling out of breath” in the first 15 to 30 seconds of an activity, Stamatakis says.

Regular daily activities offer several opportunities for these vigorous bursts, he says. “The simplest one is maximizing walking pace for a minute or two during any regular walk.” Other options, he says, include carrying grocery bags to the car or taking the stairs. “The largest population health gains will be realized by finding ways to get the least physically active people to move a little more.”

Look closely at a snowflake, and you’ll observe a one-of-a-kind gossamer lattice, its growth influenced by ambient conditions like temperature and humidity. Turns out, this sort of intricate self-assemblage can also occur in metals, researchers report in the Dec. 9 Science.

In pools of molten gallium, physicist Nicola Gaston and colleagues grew zinc nanostructures with symmetrical, hexagonal crystal frameworks. Such metal snowflakes could be useful for catalyzing chemical reactions and constructing electronics, says Gaston, of the MacDiarmid Institute for Advanced Materials and Nanotechnology at the University of Auckland in New Zealand.

“Self-assembly is the way nature makes nanostructures,” she says. “We’re trying to learn to do the same things.” Figuring out how to craft tiny, complex metal shapes in fewer steps and with less energy could be a boon for manufacturers.

The researchers chose gallium as a growth medium, due to its relatively low melting point, ability to dissolve many other metals and the tendency for its atoms to loosely organize while in a liquid state.

After mixing zinc into the gallium, the team subjected the alloy to elevated temperatures and different pressures, and then let the mixture cool to room temperature. The loose ordering of gallium atoms appeared to coax the crystallizing zinc to bloom into symmetrical, hexagonal structures resembling natural snowflakes and other shapes, the team found. It’s somewhat like how a fruit tray imparts order on the fruits stacked within, Gaston says.

The future may be bright for research into applications of gallium and other low-temperature liquid metals. “Not to take that snowflake metaphor too far, but [this work] really hints at new branches for scientific discovery,” Gaston says.

Meet the metric system’s newest prefixes: ronna-, quetta-, ronto- and quecto-.

Adopted November 18 at the 27th General Conference on Weights and Measures in Versailles, France, ronna- and quetta- describe exceedingly large numbers while ronto- and quecto- describe the exceedingly small. This is the first time that the International System of Units, or SI, has expanded since 1991, when the prefixes zetta-, yotta-, zepto and yocto- were added (SN: 1/16/93).

Numerically, ronna- is 1027 (that’s a digit followed by 27 zeroes) and quetta- is 1030 (30 zeroes). Their tiny counterparts ronto- and quecto- also refer to 27 and 30 zeroes, but those come after a decimal point. Until now, yotta- and yocto- (24 zeros) capped off the metric system’s range.

Science News spoke with Richard Brown, head of metrology at the National Physical Laboratory in Teddington, England, about what the latest SI expansion means for science. The following conversation has been edited for clarity and brevity.

SN: Why do we need the new prefixes?

Brown: The quantity of data in the world is increasing exponentially. And we expect that to continue to increase and probably accelerate because of quantum computing, digitalization and things like that. At the same time, this quantity of data is starting to get close to the top range of the prefixes we currently use. People start to ask what comes next?

SN: Where do the prefix names come from?

Brown: About five years ago, I heard a BBC podcast about these new names for quantities of data. And the two that they mentioned were brontobyte and hellabyte. Brontobyte, I think comes from brontosaurus being a big dinosaur and hellabyte comes from “‘hell of a big number.”

The problem with those from a metrology point of view, or measurement point of view, is they start with letters B and H, which already are in use for other units and prefixes. So we can’t have those as names. [It was clear] that we had to do something official because people were starting to need these prefixes. R and Q are not used for anything else, really, in terms of units or SI prefixes. [The prefix names themselves are] very, very loosely based on the Greek and Latin names for nine and 10.
SN: How will the prefixes be used?

Brown: The whole point of the International System of Units is it’s an accepted global system, which if you use, you will be understood.

When you use a prefix with a unit, it means that the number associated with the unit changes. And people like small numbers that they can understand. So you can express the mass of the Earth in terms of ronnagrams; it’s six ronnagrams. And equally the mass of Jupiter is two quettagrams. Some good examples of [small numbers] are that the mass of an electron is about one rontogram, and the mass of one bit of data as stored on a mobile phone is around one quectogram.

I think the use of a suitable prefix makes things more understandable. And I think we shouldn’t forget that even if there’s not always a direct scientific usage immediately, they will gain traction over time.

Tyrannosaurus rex isn’t just a king to paleontologists — the dinosaur increasingly reigns over the world of art auctions. A nearly complete skeleton known as Stan the T. rex smashed records in October 2020 when a bidding war drove its price to $31.8 million, the highest ever paid for any fossil. Before that, Sue the T. rex held the top spot; it went for $8.3 million in 1997.

That kind of publicity — and cachet — means that T. rex’s value is sky-high, and the dinosaur continues to have its teeth firmly sunk into the auction world in 2022. In December, Maximus, a T. rex skull, will be the centerpiece of a Sotheby’s auction in New York City. It’s expected to sell for about $15 million.

Another T. rex fossil named Shen was anticipated to sell for between $15 million and $25 million at a Christie’s auction in Hong Kong in late November. However, the auction house pulled it over concerns about the number of replica bones used in the fossil.
“These are astronomical sums of money, really surprising sums of money,” says Donna Yates, a criminologist at Maastricht University in the Netherlands who studies high-value collectibles.

Stan’s final price “was completely unexpected,” Yates says. The fossil was originally appraised at about $6 million — still a very large sum, though nothing like the final tally, which was the result of a three-way bidding war.

But the staggering amounts of money T. rex fossils now fetch at auction can mean a big loss for science. At those prices, the public institutions that might try to claim these glimpses into the deep past are unable to compete with deep-pocketed private buyers, researchers say.

One reason for the sky-high prices may be that T. rex fossils are increasingly being treated more like rare works of art than bits of scientific evidence, Yates says. The bones might once have been bought and sold at dusty “cowboy fossil” dealerships. But nowadays these fossils are on display in shiny gallery spaces and are being appraised and marketed as rare objets d’art. That’s appealing to collectors, she adds: “If you’re a high-value buyer, you’re a person who wants the finest things.”

But fossils’ true value is the information they hold, says Thomas Carr, a paleontologist at Carthage College in Kenosha, Wis. “They are our only means of understanding the biology and evolution of extinct animals.”

Keeping fossils of T. rex and other dinosaurs and animals in public repositories, such as museums, ensures that scientists have consistent access to study the objects, including being able to replicate or reevaluate previous findings. But a fossil sold into private or commercial hands is subject to the whim of its owner — which means anything could happen to it at any time, Carr says.
“It doesn’t matter if [a T. rex fossil] is bought by some oligarch in Russia who says scientists can come and study it,” he says. “You might as well take a sledgehammer to it and destroy it.”

A desire for one’s own T. rex
There are only about 120 known specimens of T. rex in the world. At least half of them are owned privately and aren’t available to the public. That loss is “wreaking havoc on our dataset. If we don’t have a good sample size, we can’t claim to know anything about [T. rex],” Carr says.

For example, to be able to tell all the ways that T. rex males differed from females, researchers need between 70 and 100 good specimens for statistically significant analyses, an amount scientists don’t currently have.

Similarly, scientists know little about how T. rex grew, and studying fossils of youngsters could help (SN: 1/6/20). But only a handful of juvenile T. rex specimens are publicly available to researchers. That number would double if private specimens were included.

Museums and academic institutions typically don’t have the kind of money it takes to compete with private bidders in auctions or any such competitive sales. That’s why, in the month before Stan went up for auction in 2020, the Society for Vertebrate Paleontology, or SVP, wrote a letter to Christie’s asking the auction house to consider restricting bidding to public institutions. The hope was that this would give scientists a fighting chance to obtain the specimens.

But the request was ignored — and unfortunately may have only increased publicity for the sale, says Stuart Sumida, a paleontologist at California State University in San Bernardino and SVP’s current vice president. That’s why SVP didn’t issue a public statement this time ahead of the auctions for Shen and Maximus, Sumida says, though the organization continues to strongly condemn fossil sales — whether of large, dramatic specimens or less well-known creatures. “All fossils are data. Our position is that selling fossils is not scientific and it damages science.”

Sumida is particularly appalled at statements made by auction houses that suggest the skeletons “have already been studied,” an attempt to reassure researchers that the data contained in that fossil won’t be lost, regardless of who purchases it. That’s deeply misleading, he says, because of the need for reproducibility, as well as the always-improving development of new analysis techniques. “When they make public statements like that, they are undermining not only paleontology, but the scientific process as well.”

And the high prices earned by Stan and Sue are helping to drive the market skyward, not only for other T. rex fossils but also for less famous species. “It creates this ripple effect that is incredibly damaging to science in general,” Sumida says. Sotheby’s, for example, auctioned off a Gorgosaurus, a T. rex relative, in July for $6.1 million. In May, a Deinonychus antirrhopus — the inspiration for Jurassic Park’s velociraptor — was sold by Christie’s for $12.4 million.

Protecting T. rex from collectors
Compounding the problem is the fact that the United States has no protections in place for fossils unearthed from the backyards or dusty fields of private landowners. The U.S. is home to just about every T. rex skeleton ever found. Stan, Sue and Maximus hail from the Black Hills of South Dakota. Shen was found in Montana.

As of 2009, U.S. law prohibits collecting scientifically valuable fossils, particularly fossils of vertebrate species like T. rex, from public lands without permits. But fossils found on private lands are still considered the landowner’s personal property. And landowners can grant digging access to whomever they wish.
Before the discovery of Sue the T. rex (SN: 9/6/14), private owners often gave scientific institutions free access to hunt for fossils on their land, says Bridget Roddy, currently a researcher at the legal news company Bloomberg Law in Washington, D.C. But in the wake of Sue’s sale in 1997, researchers began to have to compete for digging access with commercial fossil hunters.

These hunters can afford to pay landowners large sums for the right to dig, or even a share of the profits from fossil sales. And many of these commercial dealers sell their finds at auction houses, where the fossils can earn far more than most museums are able to pay.

Lack of federal protections for paleontological resources found on private land — combined with the large available supply of fossils — is a situation unique to the United States, Roddy says. Fossil-rich countries such as China, Canada, Italy and France consider any such finds to be under government protection, part of a national legacy.

In the United States, seizing such materials from private landowners — under an eminent domain argument — would require the government to pay “just compensation” to the landowners. But using eminent domain to generally protect such fossils wouldn’t be financially sustainable for the government, Roddy says, not least because most fossils dug up aren’t of great scientific value anyway.

There may be other, more grassroots ways to at least better regulate fossil sales, she says. While still a law student at DePaul University in Chicago, Roddy outlined some of those ideas in an article published in Texas A&M Journal of Property Law in May.

One option, she suggests, is for states to create a selective sales tax attached to fossil purchases, specifically for buyers who intend to keep their purchases in private collections that are not readily available to the public. It’s “similar to if you want to buy a pack of cigarettes, which is meant to offset the harm that buying cigarettes does to society in general,” Roddy says. That strategy could be particularly effective in states with large auction houses, like New York.

Another possibility is to model any new, expanded fossil preservation laws on existing U.S. antiquities laws, intended to preserve cultural heritage. After all, Roddy says, fossils aren’t just bones, but they’re also part of the human story. “Fossils have influenced our folklore; they’re a unifier of humanity and culture rather than a separate thing.”

Though fossils from private lands aren’t protected, many states do impose restrictions on searches for archaeological and cultural artifacts, by requiring those looking for antiquities to restore excavated land or by fining the excavation of certain antiquities without state permission. Expanding those restrictions to fossil hunting, perhaps by requiring state approval through permits, could also give states the opportunity to purchase any significant finds before they’re lost to private buyers.

Preserving fossils for science and the public
Such protections could be a huge boon to paleontologists, who may not even know what’s being lost. “The problem is, we’ll never know” all the fossils that are being sold, Sumida says. “They’re shutting scientists out of the conversation.”

And when it comes to dinosaurs, “so many of the species we know about are represented by a single fossil,” says Stephen Brusatte, a paleontologist at the University of Edinburgh. “If that fossil was never found, or disappeared into the vault of a collector, then we wouldn’t know about that dinosaur.”

Or, he says, sometimes a particularly complete or beautifully preserved dinosaur skeleton is found, and without it, “we wouldn’t be able to study what that dinosaur looked like, how it moved, what it ate, how it sensed its world, how it grew.”

The point isn’t to put restrictions on collecting fossils so much as making sure they remain in public view, Brusatte adds. “There’s nothing as magical as finding your own fossils, being the first person ever to see something that lived millions of years ago.” But, he says, unique and scientifically invaluable fossils such as dinosaur skeletons should be placed in museums “where they can be conserved and studied and inspire the public, rather than in the basements or yachts of the oligarch class.”

After its record-breaking sale, Stan vanished for a year and a half, its new owners a mystery. Then in March 2022, news surfaced that the fossil had been bought by the United Arab Emirates, which stated it intends to place Stan in a new natural history museum.

Sue, too, is on public view. The fossil is housed at Chicago’s Field Museum of Natural History, thanks to the pooled financial resources of the Walt Disney Corporation, the McDonald Corporation, the California State University System and others. That’s the kind of money it took to get the highest bid on a T. rex 25 years ago.

And those prices only seem to be going up. Researchers got lucky with Sue, and possibly Stan.

As for Shen, the fossil’s fate remains in limbo: It was pulled from auction not due to outcry from paleontologists, but over concerns about intellectual property rights. The fossil, at 54 percent complete, may have been supplemented with a polyurethane cast of bones from Stan, according to representatives of the Black Hills Institute of Geological Research in Hill City, S.D. That organization, which discovered Stan, retains a copyright over the skeleton.

In response to those concerns, Christie’s pulled the lot, and now says that it intends to loan the fossil to a museum. But this move doesn’t reassure paleontologists. “A lot of people are pleased that the sale didn’t go through,” Sumida says. “But it sort of just kicks the can down the road.… It doesn’t mean they’re not going to try and sell it in another form, somewhere down the road.”

Ultimately, scientists simply can’t count on every important fossil finding its way to the public, Carr says. “Those fossils belong in a museum; it’s right out of Indiana Jones,” he says. “It’s not like they’re made in a factory somewhere. Fossils are nonrenewable resources. Once Shen is gone, it’s gone.”

The infant universe transforms from a featureless landscape to an intricate web in a new supercomputer simulation of the cosmos’s formative years.

An animation from the simulation shows our universe changing from a smooth, cold gas cloud to the lumpy scattering of galaxies and stars that we see today. It’s the most complete, detailed and accurate reproduction of the universe’s evolution yet produced, researchers report in the November Monthly Notices of the Royal Astronomical Society.

This virtual glimpse into the cosmos’s past is the result of CoDaIII, the third iteration of the Cosmic Dawn Project, which traces the history of the universe, beginning with the “cosmic dark ages” about 10 million years after the Big Bang. At that point, hot gas produced at the very beginning of time, about 13.8 billion years ago, had cooled to a featureless cloud devoid of light, says astronomer Paul Shapiro of the University of Texas at Austin.
Roughly 100 million years later, tiny ripples in the gas left over from the Big Bang caused the gases to clump together (SN: 2/19/15). This led to long, threadlike strands that formed a web of matter where galaxies and stars were born.

As radiation from the early galaxies illuminated the universe, it ripped electrons from atoms in the once-cold gas clouds during a period called the epoch of reionization, which continued until about 700 million years after the Big Bang (SN: 2/6/17).

CoDaIII is the first simulation to fully account for the complicated interaction between radiation and the flow of matter in the universe, Shapiro says. It spans the time from the cosmic dark ages and through the next several billion years as the distribution of matter in the modern universe formed.

The animation from the simulation, Shapiro says, graphically shows how the structure of the early universe is “imprinted on the galaxies today, which remember their youth, or their birth or their ancestors from the epoch of reionization.”

An ancient hominid dubbed Homo naledi may have lit controlled fires in the pitch-dark chambers of an underground cave system, new discoveries hint.

Researchers have found remnants of small fireplaces and sooty wall and ceiling smudges in passages and chambers throughout South Africa’s Rising Star cave complex, paleoanthropologist Lee Berger announced in a December 1 lecture hosted by the Carnegie Institution of Science in Washington, D.C.

“Signs of fire use are everywhere in this cave system,” said Berger, of the University of the Witwatersrand, Johannesburg.

H. naledi presumably lit the blazes in the caves since remains of no other hominids have turned up there, the team says. But the researchers have yet to date the age of the fire remains. And researchers outside Berger’s group have yet to evaluate the new finds.

H. naledi fossils date to between 335,000 and 236,000 years ago (SN: 5/9/17), around the time Homo sapiens originated (SN: 6/7/17). Many researchers suspect that regular use of fire by hominids for light, warmth and cooking began roughly 400,000 years ago (SN: 4/2/12).

Such behavior has not been attributed to H. naledi before, largely because of its small brain. But it’s now clear that a brain roughly one-third the size of human brains today still enabled H. naledi to achieve control of fire, Berger contends.

Last August, Berger climbed down a narrow shaft and examined two underground chambers where H. naledi fossils had been found. He noticed stalactites and thin rock sheets that had partly grown over older ceiling surfaces. Those surfaces displayed blackened, burned areas and were also dotted by what appeared to be soot particles, Berger said.

Meanwhile, expedition codirector and Wits paleoanthropologist Keneiloe Molopyane led excavations of a nearby cave chamber. There, the researchers uncovered two small fireplaces containing charred bits of wood, and burned bones of antelopes and other animals. Remains of a fireplace and nearby burned animal bones were then discovered in a more remote cave chamber where H. naledi fossils have been found.

Still, the main challenge for investigators will be to date the burned wood and bones and other fire remains from the Rising Star chambers and demonstrate that the fireplaces there come from the same sediment layers as H. naledi fossils, says paleoanthropologist W. Andrew Barr of George Washington University in Washington, D.C., who wasn’t involved in the work.

“That’s an absolutely critical first step before it will be possible to speculate about who may have made fires for what reason,” Barr says.

Marsupials may have richer social lives than previously thought.

Generally considered loners, the pouched animals have a wide diversity of social relationships that have gone unrecognized, a new analysis published October 26 in Proceedings of the Royal Society B suggests. The findings could have implications for how scientists think about the lifestyles of early mammals.

“These findings are helpful to move us away from a linear thinking that used to exist in some parts of evolutionary theory, that species develop from supposedly simple into more complex forms,” says Dieter Lukas, an evolutionary ecologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who was not involved with the study.

Mammals run the gamut of social organization systems, ranging from loose, ephemeral interactions like aggregations of jaguars in the South American wetlands to the antlike subterranean societies of naked mole-rats (SN: 10/13/21; SN: 10/20/20).

But marsupials — a subgroup of mammals that give birth to relatively underdeveloped young reared in pouches — have traditionally been considered largely solitary. Some kangaroo species were known to form transient or permanent groups of dozens of individuals. But among marsupials, long-term bonds between males and females were thought rare and there were no known examples of group members cooperating to raise young. Previous work on patterns of mammalian social evolution regarded about 90 percent of examined marsupial species to be solitary.

“If you look at other [studies] about some specific species, you will see [the researchers] tend to assume that the marsupials are solitary,” says Jingyu Qiu, a behavioral ecologist at CNRS in Strasbourg, France.

Sorting social lives
Qiu and her colleagues developed a database of field studies that illuminated marsupial social organization, taking into account how populations vary within a species and delving into the evolutionary history of marsupial social lives. The researchers compiled data from 120 studies on 149 populations of 65 marsupial species, categorizing each population as solitary, living in pairs — such as one male and one female — or falling into four kinds of group living, including one male and multiple females (or vice versa), multiple males and females, or single sex groups.

While 19 species, or 31 percent of those studied, appear to go strictly solo, nearly half of the species always live in pairs or groups. The team also found lots of variation within species; 27 of the 65 species — more than 40 percent — fell into multiple social organization classifications.
When the researchers looked at this social variation against climatic conditions in Australia, they found that social variability was more common in drier environments with less predictable rainfall. It’s possible that being able to switch between solitary and group living acts as a buffer against resource unpredictability.

The researchers’ focus on social flexibility “highlights that there is nothing simple even about a supposedly solitary species,” Lukas says.

Implications for the earliest mammals
Qiu and her colleagues also ran computer analyses comparing the evolutionary relationships of the marsupials with how they form social relationships. This let the team predict the social organization of the earliest marsupials, which split from placental mammals about 160 million years ago. Because modern marsupials have been considered solitary, the marsupial ancestors — and the earliest mammals on the whole — have generally been assumed to be solitary as well.

The team found that solitary was the most likely social category of the ancestral marsupials, a 35 percent probability. But Qiu points out that the varied combinations where pair and group living are possible options make up the other 65 percent. So “it is more likely that the ancestor was also non-solitary,” she says. The findings also give insights into the range of possible lifestyles experienced by the earliest mammals, she says.

But Robert Voss, a mammalogist at the American Museum of Natural History in New York City, questions the analyses’ insights about a potentially social ancestral marsupial. The uncertainty about the solitary alternative, he says, is largely due to the researchers’ benchmarks for what does and what doesn’t constitute social behavior — thresholds that Voss views as too permissive. For example, Voss disagrees with the team’s characterization of opossum social organization.

“Anecdotal observations of [members of the same species] occasionally denning together is not compelling evidence for social behavior,” says Voss. “None of the cited studies suggest that opossums are anything other than solitary.”

Future work, Qiu says, will involve gathering data on a larger subset of mammals outside of marsupials to get a clearer picture of how social traits have evolved among mammals.

A sacrificed spider monkey is shedding new light on an ancient Mesoamerican relationship.

The remains of a 1,700-year-old monkey found in the ancient city of Teotihuacan outside modern-day Mexico City suggest the primate was a diplomatic gift from the Maya. The find is the earliest evidence of a primate held in captivity in the Americas, researchers report November 21 in Proceedings of the National Academy of Sciences.

Unearthed in 2018 at the base of a pyramid in Teotihuacan, the monkey’s skeleton lay beside the corpses of other animals — including an eagle and several rattlesnakes — in an area of the city where visiting Maya elites may have resided.

Evidence of animal sacrifices, including of predators like jaguars, have been found in the city before. But “up to that point, we did not have any instances of sacrificed primates in Teotihuacan,” says Nawa Sugiyama, an anthropological archaeologist at the University of California, Riverside.

Chemical analysis of the spider monkey’s bones and teeth showed that the female had likely been captured in a humid environment at a young age sometime in the third century. The monkey then lived in captivity for a few years before meeting her end between the years 250 and 300.

The highlands around Mexico City are a long way from the natural habitat of spider monkeys (Ateles geoffroy), which require wet tropical forests to thrive. This fact, along with the presence of Maya murals and vessels, suggests to Sugiyama and her colleagues that the spider monkey was a gift from elite Mayas to the people of Teotihuacan.

The find is an example of diplomatic relations between two cultures that sometimes had violent interactions. Maya hieroglyphs indicated that military forces from Teotihuacan invaded the Maya city of Tikal in 378, marking the start of a roughly 70-year period in which Teotihuacan meddled in Maya politics (SN: 10/22/21).

The “striking” discovery of the monkey shows that relationship between these two cultures far predates the invasion, says David Stuart, an archaeologist and epigraphist at the University of Texas at Austin who was not involved in the study.

“The war of 378 had a long history leading up to it,” he says. “The monkey is a really compelling illustration of this long relationship.”