The oldest DNA recovered so far is 2 million years old

The messy story of humanity's genealogical past

For decades, scientists viewed the human fossil record and concluded Neanderthals, an early hominin, came before homo sapiens, or modern humans. The story became more complicated as technology advanced and ancient DNA samples were analyzed. This video breaks down the evidence, concluding the development of humanity was a lot messier than previously believed.

A timeline of human fossil discoveries

A key part of writing a coherent story about our origins is finding and identifying the remains of our ancestors and understanding their significance. Scientists will not always agree on identifications and opinions will change as new find are made and new ways of studying them are developed.

In 2025, UK scientists began studying climate data from a 1.5-million-year-old ice core

The Antarctica sample will be melted and analyzed in Cambridge to learn about prehistoric environmental conditions. Researchers hope the ice core reveals how Earth's glacial cycles shifted dramatically around 800,000 years ago.

The earliest evidence of cancer was found in a 1.7-million-year-old fossil—discovered in the toe of an ancestor of modern-day humans.

Billion-year-old Arctic fossils suggest Earth had fungi far earlier than previously thought

Named Ourasphaira giraldae, this new species of fungus, reported in 2019, was found in the Grassy Bay Formation in the Canadian Arctic. It pushed the fossil record of fungi back by about half a billion years since the oldest previously recognized fungi fossils came from the Rhynie chert, a Scottish site that dates back roughly 400 million years. This fungal discovery also suggests that fungi may have occurred on land much earlier than plants, raising questions about what ancient fungi used for nourishment.

Storing data in DNA requires converting binary code into DNA's four-base system

Researchers have suggested that DNA's ability to form compact, dense structures justifies investigating its use for long-term, safe data archiving. This system could fit all of the world's data in a single shoebox, though processing each bit into a nucleotide base takes 2 minutes, as of 2024.

Think we decoded the genome in 2000? Nope. It was 2022.

Two decades after the draft sequence of the human genome was unveiled to great fanfare, a team of 99 scientists has finally deciphered the entire thing. They have filled in vast gaps and corrected a long list of errors in previous versions, giving us a new view of our DNA.

Despite privacy risks, scientists are using DNA in the air to assess ecosystem health

While DNA in soil and water samples has long been used for such analyses, airborne DNA is being incorporated into such efforts to monitor individual species abundance, detect invasive species, measure biodiversity, and determine the success of conservation actions. Future work may include detecting attacks from biological weapons.

View a collection of historical documents about molecular biology's history

The collection features materials related to those involved in the discovery of DNA and provides historical context for the discoveries of RNA, various viruses, and important bioproteins. The items include photographs, business correspondence, manuscripts, and scientific instruments.

A cave painting might be the oldest illustrated story ever recorded

A nearly 44,000-year-old cave painting may be the oldest story ever recorded, offering viewers a tale of human-like creatures on a hunt. This article details the discovery of the cave and its archaeological implications.

The discovery of the first extremophile and how it revolutionized DNA analysis

While investigating samples taken from within and around the hot springs at Yellowstone National Park, microbiologist Thomas Brock discovered Thermus aquaticus, a microorganism that thrived in hot water. It contained an enzyme called Taq polymerase, a critical molecule in polymerase chain reaction—a molecular photocopier that amplifies genetic signals to improve medical diagnostics.

A fascinating look at how our DNA is built and replicated

This easy-to-understand 13-minute video dives into the wondrous molecule deoxyribonucleic acid – also known as DNA – and explains how it replicates itself in our cells.

Human settlements may be older than previously thought

This narrative article follows an archaeological team as they sift through the remains of Nahal Ein Gev II, an ancient village near the Sea of Galilee in Israel. Abandoned about 12,000 years ago, the site has been investigated for years and...

Why are archaeologists brewing ancient beers?

Archaeologists have managed to brew beer from yeast found inside jugs abandoned thousands of years ago. This article explores why scientists are recreating these ancient beverages and what they hope to learn. People have been drinking beer for...

Why genetic similarities between humans suggest a past near-extinction event

Researchers have found that low genetic diversity among humans—even those on opposite sides of the planet—may result from a breeding population of as few as 1,280 adults, estimated to have existed 930,000 years ago. This genetic bottleneck may have resulted from a near-extinction or from a small population of human ancestors, from which we all descend, that broke off from a larger population.

Archaeologists decode the first known sentence in what may be the oldest written alphabet

This five-minute video details the accidental discovery and subsequent decoding of the first known sentence in what's believed to be the oldest written alphabet. The Canaanite sentence was found on a Bronze Age hair comb unearthed in Tel Lachish, a city of the ancient Biblical Kingdom of Judah, during a dig focused on excavating the kingdom's first Iron Age city. The Canaanite language developed sometime between 3,000 and 1,000 BCE.

Explore these collections of early human fossils

The human fossil record is filled with massive gaps, leaving archaeologists tiny samples to try and glean the history of our species. At this site, you can browse through the human fossil collection, including 3D rotatable scans of hundreds of fossils from different species of early humans.

How paleos dig up dinosaurs

Follow Kelsie Abrams and the dig team from the field to the lab, as they unravel mysteries from the end of the age of dinosaurs.

How do we know what prehistoric humans ate?

Without recourse to ancient menus, how can historians know what our ancient human ancestors—as far as 3 million years ago—ate on a daily basis? Researchers evaluate several factors, including the type of teeth the species had evolved, chemical analysis of the teeth, patterns of wear and tear on teeth, as well as food scraps found in the vicinity of ancient remains. Learn the approach to discovering ancient hominin diets.

Scientists can suck animal DNA from the air

A look at how researchers filtered the air around two zoos and identified genetic material from dozens of species, a technique that could help track and conserve wildlife.

How old are stone tools?

The earliest evidence for stone tools currently dates back to 3.3 million years ago, long before modern humans started roaming about. These tools were made by stone flaking, a mode of tool creation that still is used today and is done by striking...

DNA computing allows for storage and processing of massive amounts of data

Although costly and less efficient for simpler tasks, as of 2025, DNA could hold 455 exabytes of data with near limitless parallel computation potential in small data centers. Every movie ever made would fit inside the volume of a single sugar cube.

Up to 8% of the human genome consists of ancient viral DNA

Human endogenous retroviruses are remnants of infections that affected human primate ancestors millions of years ago and were passed on by infiltrating sperm and egg cells. Studies have shown that this DNA may play a role in immune responses and in placental formation.

Searching for the history of cancer in ancient human bones

Nestled under archaeology lies bioarchaeology, which involves the study of bones, human or animal. This subfield recently birthed another field of study: paleo-oncology. Paleo-oncology looks for cancer and related biomarkers in bioarchaeological remains. This TED article explains how this nascent multidisciplinary field challenges the idea that cancer is modern.

Where do genes come from?

There are many more genes on Earth today than when microbial life first spawned on the planet about four billion years ago. Many of these newer genes grew from genetic mutations, misprints that slowly drift from the original blueprint via cellular division. If these mutations drift far enough, they can establish a new family of genes, though this process can take well over a million years.

Paleontologists apply rules about rock layering, fossilization, and radioactivity to date geological samples

Concepts such as the understanding that older rock layers will form beneath newer ones allow scientists to compare the ages of samples from various layers. Although no geological site preserves evidence across all time, samples can be combined with fossils of known age, such as those dated by analyzing the decay of their radioactive isotopes, to reconstruct Earth's timeline.

Read the academic article explaining how ancient smells can be dissected and recreated

This paper explores how biomolecular data on past scents can be teased out and then transformed into olfactory museum experiences, adding another component to our understanding of archaeology.

A look at the Kidd Creek Mine in Canada, which houses the world's oldest isolated water

The mine sits on the Precambrian Canadian Shield—an ocean floor dating back 2.7 billion years. Exhibiting a musty smell, the water is 10 times saltier than seawater and offers insights into Earth's ancient seabed.

Molecular evidence suggests the deadliest malaria parasite may be 100,000 years old.

Genetic analysis indicates that every organism on Earth evolved from a single cell

LUCA—the last universal common ancestor—lived about 4.2 billion years ago and likely obtained energy through the conversion of carbon dioxide and hydrogen gas consumed from atmospheric gases at the ocean's surface or hydrothermal vents—openings on the seafloor where fluid warmed and enriched with minerals by Earth's interior is expelled.

As of 2025, humans have only dug 0.2% the way to Earth's center

The Kola Superdeep Borehole revealed two billion-year-old fossils and underground water, but the immense temperature and pressure prevented further tunneling. Beyond those depths, scientists know of Earth's interior by analyzing how seismic waves move.

The history of the gene: an interactive timeline

Humans didn’t need modern technology to figure out that kids tend to look like their parents. But what did humans believe about genetics before we knew about DNA or cells in general? Explore this interactive timeline to see how philosophers and scientists throughout the ages tried to explain how traits are passed from generation to generation.

Genomic sequencing is the process of determining the order of nucleotides that make up an organism's genetic information and can be done in about 24 hours or less for human DNA.

Fossils suggest tardigrades developed cryptobiosis more than 180 million years ago

As of 2024, three tardigrade fossils have been discovered, all preserved in amber. Analysis suggests different species of the organism existed over 500 million years ago, when marine heterotardigrades and freshwater terrestrial eutardigrades diverged. (Some readers may experience a paywall.)

How humans evolved from single-cell organisms

Humans have had a long history. 3.8 billion years in the making, to be precise. From the primordial puddle to the modern day, here's how humans have evolved from the first life.

Evidence suggests the first cells on Earth were bacteria

About 4 billion years ago, these single-celled organisms harvested carbon dioxide and sunlight to produce their own food and oxygen, setting the stage for the evolution of oxygen-breathing life forms. Archaeabacteria, which thrive on inorganic molecules in extreme habitats on Earth today, were also among the earliest organisms.

What can we learn from archaeology?

By revealing buried civilizations and dating objects of antiquity, archaeology turns hard data into human stories. But what's the use of knowing these stories? Find out for yourself in this interactive resource that can take you to and through historic sites around the globe.

Cadaver dogs are helping archaeologists uncover decaying history

Archaeologists are increasingly relying on dogs to help find decaying bodies at burial sites, some of them up to thousands of years old. This is helping archaeologists to detect past remains without ever touching a shovel, which means there's less...

All humans share 99.9% of the same DNA

Of the 3 billion base pairs that make up the human genome—the complete set of genetic material for the species—the diversity of humans is the result of variations in about 3 million molecular bases. The closest nonhuman genetic match is the chimp, with 98.8% similar genetics.

Like counting how often a word is repeated in a sentence, forensic scientists can identify people by tallying how often short segments of genetic information repeat in specific parts of a person's DNA—a set of numbers that varies from person to person.

The lifestyles of early humans

For 2.5 million years, humans lived on Earth without leaving a written record of their lives—but they left behind other kinds of remains and artifacts.

Scientists can determine the age of rocks, fossils, and other ancient samples by measuring how many radioactive atoms in the sample have decayed, a process that occurs at precise, well-known rates.

Santa Barbara's Channel Islands revealed the oldest skeletal remains in North America

IN 1959, archaeologists found a human femur jutting out from a rock face on Santa Rosa Island. Using the then-new technology of radiocarbon dating, they measured the age of the remains at 13,000 years—the oldest in the continent.

Scientists use climate proxies—physical, chemical, and biological materials preserved in sediments, ice, and fossils—to infer historical climate data and determine past climate patterns.

The Dokos shipwreck, the oldest discovered to date, is more than 4,000 years old

Many of the oldest shipwrecks yet discovered sank during the late Bronze Age as Mediterranean trade networks began to flourish. This video explores the nine oldest wreckage sites, topped by the wreck off the Greek island of Dokos.

Ancient humans and other early hominins were closer than you might think

Evidence that human ancestors and other early hominins coexisted continues to accumulate, raising the question of just how close these ancient people truly were. This article details how evidence is changing the theory that early hominins like...

Ancestry testing matches DNA to known genetic variants found in specific ancestries

After a lab receives a person's sample, the DNA is separated into single strands, which are chemically cut into smaller fragments. The fragments are then fed into an array of variants of known origins, and technicians observe if a person's fragments bind to specific variants.

Why your dog’s DNA isn’t destiny

DNA tests tell people about their pet’s breed and attempt to predict things about its behavior and health. But for all that these tests might provide some interesting results, they need to be taken with caution. Here's a look at what we can and can't learn from our pets' DNA.

The archaeological discovery that shifted scientists' understanding of human evolution

In 2003, archaeologists in Indonesia uncovered the remains of a 3-foot-tall skeleton that appeared to belong to a new type of human. Read this article to learn how the discovery of this 50,000-year-old skeleton upended the idea that human evolution...

A four-billion-year-old meteorite reignited the debate about life on Mars

Recovered from Antarctica in 1984, ALH84001 contained organic compounds, magnetite and iron sulfide grains of potential biological origin, and features that resembled fossilized bacteria. With technological advancements, scientists found abiotic origins for these features in the following decades.