Technologies

2 Million-Year-Old DNA, the Oldest Ever Recovered, Opens Window to the Past

The prehistoric forest of northern Greenland was home to mastodons, reindeer, hares and an abundance of plant life.

As early as 2006, Eske Willerslev and members of his lab ventured into northern Greenland with a drill, extracting cores of sediment from the Kap København Formation. They were hunting for environmental DNA, or eDNA, in their cores — puzzle pieces that could help paint a picture of the plants and animals present in the region 2 million years ago.

But for the longest time, they came up empty-handed. «Every time we had improvements in terms of DNA extraction or sequencing technology, we’d revisit these samples,» Willerslev, an evolutionary geneticist at the University of Cambridge, said in a press briefing on Tuesday.

No matter what, the researchers failed to get what they were looking for. The run of bad luck saw members of the lab turn to the occult for an explanation; they named their troubles «the curse of the Kap København Formation.»

But with steady improvements in DNA extraction and sequencing technologies, the curse was finally broken.

On Wednesday, the team published the results of their 16-year pursuit of ancient DNA in the journal Nature. They were able to sequence eDNA from 41 sediment samples, collected in 2006, 2012 and 2016 from the Kap København Formation and undisturbed by humans for 2 million years. Their analyses revealed that a lush forest replete with reindeer, hares, mastodons and a wide variety of flora once stood in what is now a dull, gray polar desert.

Willerslev, a pioneering geneticist who has previously recovered eDNA from ice cores and shown it could survive in glaciers, noted that the «breakthrough» relied on expertise, advances in genetic sequencing techniques and bioinformatics.

History in the soil

DNA, which carries the instructions for life, is not a particularly sturdy molecule. The bonds that hold it together are weak and, over time, they break down.

This is why, even though we have an abundance of dinosaur fossils, we don’t have any dinosaur DNA. The beasts died out 66 million years ago, and the DNA would simply not survive that long.

When DNA degrades, the once-long strands of information break apart into smaller and smaller pieces. It becomes almost impossible to piece these fragments back together in the right configuration, especially if they are mixed in with a lot of other DNA from the environment.

Think of DNA like a book. Let’s say Alice in Wonderland. If you have the whole book, you can understand the story. But if you’re missing a few pages, you might not understand where the White Rabbit came from or why Alice ended up at a tea party with the Mad Hatter. If you’re missing lots of pages, you probably can’t even tell what the story was to begin with. Alice? Who’s that? And why is she 10 feet tall?

That’s the problem working with ancient DNA. You might be able to retrieve small fragments of DNA but it is generally too fragmented to be able to tell where it came from — and certainly too fragmented to understand where it came from.

But under certain circumstances, DNA fragments can survive deep time.

«The ‘survival time’ of DNA in the environment is incredibly variable and strongly dependent on the environment itself,» notes Michael Knapp, an ecologist and geneticist at Otago University in New Zealand.

Previously, the oldest DNA ever recovered came from mammoth fossils found in the Siberian permafrost. In a Nature paper in 2021, researchers showed that DNA from the mammoth teeth was, potentially, about 1.6 million years old. The DNA recovered was broken up into small fragments but they weren’t degraded so much they couldn’t be pieced back together. The cold temperature of the permafrost certainly helped with this.

It’s a similar story in the new study.

Willerslev and his collaborators postulate that the long survival time of the DNA in their sediment cores was possible for two reasons. The first is the constant cold temperature of the polar desert. The second is the way the DNA is bound to minerals in the cores, preventing degradation over longer time scales. The idea is that these mineral surfaces prevent enzymes from breaking down the DNA.

Karina Sand, a geochemist at the University of Copenhagen and co-author on the paper, explained that one of the technological leaps that enabled this feat was extracting DNA from clay and quartz minerals. The latter provided an abundance of DNA, but the former was harder to extract good DNA from. Fortunately, that leaves the door open for even older DNA extraction.

«If we can get better at extracting the DNA from the clay minerals, then we think we can go further back in time with DNA,» she said.

The research team was able to extract DNA from the sediment cores and begin to read the surviving fragments. These fragments were then compared to a database of genomes (complete DNA sequences) of modern plants and animals, looking for DNA matches. Over time, they were able to fill the blank pages of history, demonstrating the thriving ecosystem of ancient Greenland.

The ancient forest of Greenland

Two million years ago, Greenland was a different place.

«The Kap København ecosystem, which has no present-day equivalent, existed at considerably higher temperatures than we have today,» noted Mikkel Pederson, a geneticist at the Lundbeck Foundation GeoGenetics Centre, in a press release.

In northern Greenland, average temperatures during this time were likely more than 11 degrees Celsius (around 20 degrees Fahrenheit) higher than they are today. Previous studies at Kap København have shown evidence it was home to a boreal forest, but the eDNA extracted and analyzed in the new study provides a complete reimagining of the area, adding in megafauna and a wide variety of plant life.

The headline mammal DNA found in the cores is undoubtedly the mastodon — which is having a bit of a moment thanks to social media. Some of the eDNA found matched to the Elephantidae family, which includes elephants, mammoths and mastodons. It seems mastodons may have roamed Greenland 2 million years ago, though the researchers note the evidence isn’t extremely strong and is based on relatively weak DNA matches.

The team also found DNA related to reindeer, hares and rabbits, and the subfamily of animals that includes lemmings, voles and muskrats. Notably absent, however, is DNA from carnivores. The researchers suggest this is because of their comparably small biomass in relation to the herbivores. «It’s basically a numbers game,» Willerslev said.

One of the more intriguing DNA finds is of the Atlantic horseshoe crab. The species is no longer found at such northern latitudes, and the authors suggest this may mean Kap København experienced warmer sea surface temperatures 2 million years ago. Previous research has suggested the sea surface was warmer at higher latitudes, and the discovery of horseshoe crab DNA lends further support to this hypothesis.

Warmer temperatures are key. Multiple authors on the paper have reiterated the importance of understanding an ecosystem like this, given the effects of global warming. Two million years ago, the climate was changing and the eDNA shows that Arctic species were living with species that loved much warmer climes. This helps scientists to get an understanding of how nature was adapting to those changes and, within the DNA signatures, there may be clues to ways we could help modern-day fauna and flora survive extreme climatic swings.

One of the significant limitations of studying eDNA is that scientists have to postulate about the kinds of species that were living at the time. Knapp notes closely related ancient species might give you a DNA match but this is «somewhat inaccurate» — it provides an approximation of what existed. We may only be able to assign the DNA at a family or order level, so we can’t know exactly what roamed the boreal forest of Greenland 2 million years ago.

Even so, the recovery of DNA this old opens a new window to the prehistoric Earth, a pathway for scientists and researchers to probe the ecosystems that existed long before humans were around. The team will head to northern Canada to extract cores next year and hope to go even further back in time.

The extraction method may even lend itself to finding DNA in more humid climates across the world, like in Africa and Australia.

«If we can begin to explore ancient DNA in clay grains from Africa, we may be able to gather ground-breaking information about the origin of many different species —perhaps even new knowledge about the first humans and their ancestors,» Willerslev said in a statement.

«The possibilities are endless.»

Technologies

Lemon8 and TikTok Could Be Banned. Here’s How the Apps Are Different

TikTok and Lemon8 are owned by the same parent company, but they offer different experiences.

TikTok faces another sale deadline Saturday, and unless a US buyer intervenes — or President Donald Trump extends the deadline again — the app could disappear for US users. If the ban goes into effect, TikTok wouldn’t be the only app to disappear: TikTok’s sister app, Lemon8, could be caught in the crossfire.

Read more: A VPN Alone Probably Won’t Bypass TikTok Bans. Here’s Why

Lemon8 is owned by ByteDance, the same parent company that owns TikTok. It’s one of the top Lifestyle apps in Apple’s App Store, and it has more than 10 million downloads in the Google Play store.

«Lemon8 is a lifestyle community focused app powered by TikTok, where you can discover and share authentic content on a variety of topics such as beauty, fashion, travel, food, and more,» the app’s description reads in both stores.

Here’s what you need to know about Lemon8.

Note: I reached out to ByteDance for this story, and the company did not respond for comment.

What is Lemon8?

Lemon8 is a video- and photo-sharing platform that eschews the vertical-scrolling format of TikTok in favor of a Pinterest board-style format. But what Lemon8 and TikTok do have in common is that both have Following and For You tabs to show you posts from creators you follow and posts the app thinks you will like.

Lemon8’s content is split into six topic tabs, plus a seventh tab called All. The other tabs are Fashion, Beauty, Food, Wellness, Travel and Home. These tabs can be found across the top of your screen, and tapping into these tabs shows you recommended and suggested posts.

Posts can be swipeable photo collections like in Instagram, or TikTok-style videos. Some creators add text to their photos to label clothing or a product. Some will also include the price of the item in the text.

How is Lemon8 different from TikTok and other apps?

Lemon8 is different from other apps in terms of what is posted and how it’s presented.

Lemon8 has a lot of influencer ads and product recommendations. It’s difficult to tell what is and isn’t sponsored content, and this appears to be the norm across the app. TikTok also has sponsored content, but usually these are marked as such in the bottom-left corner.

There aren’t a lot of memes or jokes on Lemon8 compared to other apps, either. You can find memes on Lemon8, but various hashtags associated with «memes,» like «funnymemes» and «catmemes,» have fewer than 1 million views (as opposed to hundreds of millions on Instagram). This could be because Lemon8 is still catching on in the US, but my suspicion is Lemon8 isn’t meant for memes. It’s meant to be more of a guidebook to help you achieve a certain lifestyle or aesthetic.

There’s also a lot of writing in Lemon8. For example, post captions might include instructions for a recipe or a deeper breakdown of an outfit. TikTok captions can have useful information, but those captions are more about connecting posts to hashtags to get more views and don’t necessarily add new information to the TikTok post. Lemon8 uses captions in a similar way to Instagram posts, but Lemon8 captions have one key difference from Instagram: templates.

Lemon8 lets you use templates for your posts to help you quickly format and to give you an idea of what to caption your post. There are caption templates for fashion, shopping finds, beauty, food and travel.

Lemon8 reminds me of a mashup between the magazines Martha Stewart Living, Muscle & Fitness and Travel + Leisure. You can find some useful tips in Lemon8 to help you achieve a desired aesthetic or find some vacation inspiration, but it’s not clear what is and isn’t an ad.

What are people saying about Lemon8?

People’s reaction to Lemon8 is seemingly positive so far. One TikTok creator posted a video calling Lemon8 «Pinterest, but interactive.» Another said Lemon8 is a combination of Pinterest, Instagram and TikTok.

However, this positivity could be artificially inflated. ZDNet reports that many TikTok posts about Lemon8 have described the app with similar language, making some believe ByteDance paid these creators.

And some Lemon8 creators’ claims make this theory sound more viable. One Lemon8 creator told Insider that ByteDance paid them to post on the app. Two other Lemon8 creators showed Insider emails that outlined the app’s payment structure.

Who owns Lemon8?

ByteDance, the Chinese tech company that owns TikTok, also owns Lemon8. According to ZDNet, ByteDance is positioning Lemon8 to be an Instagram rival as more users stop using, or abandon, Meta’s app.

According to the Wall Street Journal, a leaked internal memo from Meta showed that Instagram engagement was declining. ByteDance executives could be hoping to capitalize on this by giving Instagram users an alternative app in the form of Lemon8. And while Lemon8 was released globally in 2020, the app’s recent growth might show ByteDance’s gamble is paying off.

Will Lemon8 be banned alongside TikTok?

Since Lemon8 is owned by ByteDance, which also owns TikTok, it’s possible that the app will be banned alongside TikTok on April 5.

The law requiring the sale of TikTok could be applied generally to other apps that are owned and operated by ByteDance and its subsidiaries. When TikTok shutdown operations in the US in January, Lemon8 was shutdown alongside the app. If TikTok shuts down again, Lemon8 likely will as well.

Should you download Lemon8?

Even with a shutdown looming, Lemon8 is free, so you can download and try the app now before the sale deadline. Just know the app’s posts resemble instructional guides more than memes to share, and many posts feel like advertisements.

What’s Lemon8’s privacy policy?

Most of Lemon8’s privacy policy seems standard for social media apps. It states Lemon8 collects personal and location information to provide you with a better app experience. Some collected information includes your IP address and browsing history. But part of the app’s privacy policy might raise eyebrows.

«The personal information we collect from you may be stored on a server located outside of the country where you live,» the policy reads. The company has servers around the world, according to the policy, so your information could be stored in any of them.

This is different from how Lemon8’s sister app TikTok stores some user’s data. The company stores US-based user data in Oracle servers. TikTok CEO Shou Chew said ByteDance employees in China can access this data, but with «robust cybersecurity controls and authorization approval» overseen by a US-based security team.

For more on the TikTok ban, here’s what to know about the Supreme Court’s decision, here’s what could happen next and here are other apps users are flocking to.

Technologies

Today’s NYT Connections: Sports Edition Hints and Answers for April 4, #193

Three of the four categories are especially tough today. Here are hints and the answers, for the NYT Connections: Sports Edition puzzle, No. 193, for April 4.

Looking for the most recent regular Connections answers? Click here for today’s Connections hints, as well as our daily answers and hints for The New York Times Mini Crossword, Wordle and Strands puzzles.

I only solved one of the four categories for today’s Connections: Sports Edition on my own, so if you need help, you’re not alone.

The yellow category was pretty simple, but after that I couldn’t make any connections. It might help if you know a lot about a certain NBA player’s resume. Read on for hints and the answers.

Connections: Sports Edition is out of beta now, making its debut on Super Bowl Sunday, Feb. 9. That’s a sign that the game has earned enough loyal players that The Athletic, the subscription-based sports journalism site owned by the Times, will continue to publish it. It doesn’t show up in the NYT Games app but now appears in The Athletic’s own app. Or you can continue to play it free online.

Read more: NYT Connections: Sports Edition Puzzle Comes Out of Beta

Hints for today’s Connections: Sports Edition groups

Here are four hints for the groupings in today’s Connections: Sports Edition puzzle, ranked from the easiest yellow group to the tough (and sometimes bizarre) purple group.

Yellow group hint: Do better.

Green group hint: March Madness.

Blue group hint: Six-time all-star.

Purple group hint: Think Wimbledon.

Answers for today’s Connections: Sports Edition groups

Yellow group: Not meeting expectations.

Green group: Teams in the Women’s Final Four.

Blue group: Teams Kawhi Leonard has played for.

Purple group: Ends in a piece of tennis equipment.

Read more: Wordle Cheat Sheet: Here Are the Most Popular Letters Used in English Words

What are today’s Connections: Sports Edition answers?

The yellow words in today’s Connections

The theme is not meeting expectations. The four answers are bust, disappointment, dud and failure.

The green words in today’s Connections

The theme is teams in the Women’s Final Four. The four answers are Bruins, Gamecocks, Huskies and Longhorns.

The blue words in today’s Connections

The theme is teams Kawhi Leonard has played for. The four answers are Aztecs, Clippers, Raptors and Spurs.

The purple words in today’s Connections

The theme is ends in a piece of tennis equipment. The four answers are bracket, eyeball, horseshoes and internet.

Quick tips for Connections: Sports Edition

#1: Don’t grab for the easiest group. For each word, think about other sports categories it might fit in – is this a word that can be used in football, or to describe scoring options?

#2: Second meanings are important. The puzzle loves to use last names and even college names that mean other things, to fool you into thinking they are words, not names.

#3: And the opposite is also true. Words like HURTS might seem like a regular word, but it’s also the last name of at least one pro athlete.

Technologies

Skip Your iPhone’s Lockscreen: Here’s the Hidden Flashlight Trick You Need to Know

A couple of taps can really make a difference on your iPhone.

Not long ago, your iPhone’s lockscreen would only allow two app shortcuts that you couldn’t change: camera controls and a flashlight toggle. However, iOS 18.2 allows you to customize these shortcuts to almost anything you might want. This small but impactful change is one of many ways iOS 18 supercharges customization for iPhone and iPad users. But what if you still want an easy-to-access way to toggle your flashlight without unlocking your phone?

Apple introduced an accessibility feature in iOS 14 that, once enabled, allows you to perform actions by just tapping on the back of your phone. The feature is called Tap Back and it remains a sleeper feature that’s sneakily hidden away in your settings menu. Enabling Tap Back essentially allows you to create a button on the back of your iPhone to perform an action without needing to take up any space.

Once you have Tap Back enabled, it doesn’t take long to see how much of a game-changer it can be with its added convenience. Below, we’ll show you how to set it up so a couple of taps on the back of your iPhone will let you launch just about anything you want.

For more, check out what’s in the latest iOS 18.4 release.

How to set up Back Tap on iPhone

Whether you want to link Back Tap with your flashlight, camera or launch a different iPhone app, the path through your iPhone settings begins the same way.

On your compatible iPhone (iPhone 8 or later), launch the Settings application and go to Accessibility > Touch > Back Tap. Now you have the option to launch your action (in this case, your flashlight) with either two or three taps. Although two taps is obviously faster, I would suggest three taps because if you fidget with your phone, it’s easy to accidentally trigger the accessibility feature.

Once you choose a tap option, select the Flashlight option — or a different action if you prefer. You’ll see over 30 options to choose from, including system options like Siri or taking a screenshot, to accessibility-specific functions like opening a magnifier or turning on real-time live captions. You can also set up Back Tap to open the Control Center, go back home, mute your audio, turn the volume up and down and run any shortcuts you’ve downloaded or created.

You’ll know you’ve successfully selected your choice when a blue checkmark appears to the right of the action. You could actually set up two shortcuts this way — one that’s triggered by two taps and one that’s triggered by three taps to the iPhone’s back cover.

Once you exit the Settings application, you can try out the newly enabled Back Tap feature by tapping the back of your iPhone — in my case, to turn on the flashlight. To turn off the flashlight, you can tap on the back of your iPhone as well, but you can also just turn it off from your lock screen if that’s easier.

For more great iPhone tips, here’s how to keep your iPhone screen from dimming all the time and canceling all those subscriptions you don’t want or need.