Peptides may have predated ribosomes—the cell's protein factory

RNA may have allowed life to exist before DNA

The emergence of living organisms from non-living matter—abiogenesis—requires both a molecule that encodes genetic information and proteins that perform biochemical processes. However, because DNA and protein depend on one another, some biologists theorize that RNA, which can both store information and perform functions, preceded both and originated life.

Peptide research dates back to the late 1800s

Peptide science dates back to the late 1800s with some early peptide synthesis work, but peptides took off in the medical sphere after surgeon Frederick Banting and his colleague's isolation of insulin from dog pancreases in 1921.

The word peptide comes from Greek

Originating from the Greek term "peptos," which means digestible, peptide as a word refers to two or more amino acids. (Some users may encounter a paywall.)

Peptides account for 31 of 370 new drugs approved by US FDA between 2016 and 2023

Among the approved peptide-based drugs is the first-ever treatment for Rett syndrome, a rare inherited neurologic disorder that leads to a progressive loss of motor skills and language. Peptides are particularly attractive for multiple reasons, including their ability to selectively bind to cellular receptors to either activate or inhibit their function.

Watch how proteins are created from DNA

When a DNA sequence—a gene—is activated, a copy of the activated portion is created in the form of RNA, a single-stranded version of DNA, in a process known as transcription. This RNA, called messenger RNA, leaves the nucleus and travels to a ribosome, a structure within a cell, which uses it to build a chain of organic compounds that fold into a protein.

China is producing many peptides or peptide components sold in the US

In Silicon Valley, in particular, peptides have taken off, and are often coming from China—even though many of the products are unproven for their purported uses.

Some organelles are believed to have once been independent cells

Mitochondria and chloroplasts, which are both responsible for energy production in cells, have DNA distinct from that of their host cells and are surrounded by cellular membranes resembling those of bacteria. Through symbiogenesis, these and other specialized structures were absorbed into larger cells, forming the modern-day biological units.

Biotech is trying to boost drug production efficiency—using chicken eggs

A company called Neion Bio is genetically engineering birds in a bid to produce medical compounds, a herculean task that scientists have struggled with for decades. The US FDA has approved only one chicken-derived drug in the past—an expensive treatment for a rare liver disorder. (Some users may encounter a paywall.)

Cells modify their internal spacing to improve biochemical reaction efficiencies

Studies involving microscopy and genetic engineering tools in yeast and human cells show ribosomes act as crowding agents—much like packing peanuts—and their concentrations are actively tuned to alter the rate of cellular functions. However, these concentrations and cell crowding levels vary across different tissues and cell types.

Spontaneous metabolism may give clues to origins of life

Read this article to learn more about the discovery that suggests that metabolism could have begun spontaneously on our planet—and why it means that scientists may need to rethink how we define life’s origins. A team of researchers at the...

Read a deep dive on the 'all-purpose healing' peptide BPC-157.

How mRNA vaccines work

mRNA COVID-19 vaccines were developed faster than any vaccine ever made. Even more enticing, the underlying technology may unlock preventive treatments for a wide-range of diseases.

Critical organic molecules have been found on an asteroid

NASA's OSIRIS-REx mission returned samples containing amino acids and nucleobases from asteroid Bennu. Without Bennu having been destroyed—as is common for asteroids that enter Earth's atmosphere—its samples serve as a time capsule of the solar system's early chemistry.

Snake venoms are repurposed proteins responsible for other bodily functions

Just as saliva aids digestion in humans, proteins responsible for bioactivities such as digestion and blood clotting were eventually secreted in the glands and fangs of snakes across evolutionary history. Organisms that could not withstand the effects of these molecules (e.g., excessive bloodstream clotting) became ideal prey for snakes.

Animals' stomach lining produces cheese

Cheesemaking would be impossible without rennet, the enzyme that separates milk’s liquid and solid components. Rennet occurs naturally in the stomach lining of young goats, cows, and lambs to help them digest milk, a process that also allows cheesemakers to use it to make curds. Now we have plant-based rennet that comes from thistles, artichokes, and other similar plants.

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.

Tardigrades’ intrinsically disordered proteins may help preserve biological matter

Researchers have attempted to create more drought-resistant crops by introducing proteins that help protect tardigrades in their dehydrated tun state. The proteins’ ability to stabilize molecular degradation may allow scientists to develop refrigeration-free storage for vaccines, insulin, and blood.

Umami synergy—combining glutamates and nucleotides—can amplify a meal

While glutamates are known for triggering the umami taste through specific taste receptors, nucleotides like IMP and GMP can bind alongside glutamates to enhance the receptor's response. This union explains why certain classic food combinations like bacon and eggs taste exceptionally savory.

The evolution of the human diet

Could eating like our ancestors make us healthier? One estimate suggests prehistoric hunter-gatherer communities obtained 75% of their calories from meat and fish.

Why some people have allergies

Why do some people have allergies while others don’t? One theory suggests allergies are a relic of our evolutionary past. Our immune system, once primed to fight parasites, now mistakes harmless substances for threats.

Nature simultaneously published three papers on DNA—only the first made history

Papers by Watson and Crick, Wilkins, and Franklin were fast-tracked without peer review, and their order was arranged between lab heads and editors. Franklin's appeared last, making her paper read as though supporting Watson and Crick—because they'd already incorporated her data before it was published.

Humans have speculated about alien life since ancient times

Around 50 B.C.E., Roman poet and philosopher Lucretius shared the idea that alien life was possible, which was put forth by Greek philosopher Epicurus. The writing is believed to be the first straightforward assertion in Western literature that aliens must exist.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

The hypothetical matter that neutron stars' cores may contain, including strange quarks

Models of the extreme pressures and energies in neutron stars suggest conditions resembling those believed to have existed within a fraction of a second after the Big Bang. In these environments, the quarks that make up protons and neutrons in trios may instead form pairs that combine to form one quantum object. (Some readers may experience a paywall.)

Memes can be traced back to the chain letter

Such intentional reshaping of communication transmissions dates back at least hundreds of years to the advent of the chain letter, a type of message that asks readers to create their own copy or at least forward it to others.

Pre-coin currencies like shells were subject to counterfeiting

While it is difficult to pinpoint the very earliest form of money that was used, a type of shell called cowrie shells were used as currency as far back as 3300–2000 BCE. These shells were imitated using ivory, bone, clam shells and more.

A fresco from ancient Pompeii featured an 'ancestor of modern pizza'

A team of archaeologists discovered a fresco from 79 CE featuring what appears to be a proto-pizza: a pita topped with fruit, spices, and other toppings. One archaeologist in the PBS documentary below calls it an "ancestor of modern pizza in the sense that it's a very simple, poor kind of food."

While atoms are normally made of protons, neutrons, and electrons, exotic ones have been built with antimatter—alternate versions of normal matter that live for fractions of a second and are about a billion times as rare.

Visualize how CRISPR-Cas9—a type of immune system used by single-celled organisms to attack invasive viruses—targets and makes precise changes to a gene's DNA.

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

Before humans, the Soviet Union and the United States sent animals—including apes, dogs, and cats—to space during the Space Race.

English mathematician Ada Lovelace wrote the first computer algorithm a century before computers existed and hypothesized that computing devices would one day be able to compose music—foreseeing the generative AI systems of today.

Indefinite cloning of some endangered species may not sustain their longevity because cloning success rates decrease as genetic mutations accumulate.

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

Fast-casual restaurant Chili's is experiencing a resurgence, with its parent company recently reporting a nearly 32% increase in sales, thanks to passionate Gen Z fans on TikTok.

Memecoins are a type of cryptocurrency—a form of digital currency with a wide variety of uses—created around popular 'memes,' or viral internet jokes.

When caught in the mouths of cardinal fish, seed shrimp release glowing, bioluminescent chemicals, which alert predators of the cardinal fish, prompting the shrimp's ejection.

The name 'Silicon Valley' arose from the founding of Shockley Semiconductor Laboratory in Fairchild Semiconductor in 1956-57, founded near Stanford University in Palo Alto

Graffiti dates back to at least ancient Pompeii, where citizens scrawled messages to one another on public walls

Long before Major League Baseball began allowing instant replay for balls and strikes, an umpire reluctantly used the technology to determine whether a hit was a home run, a move that inadvertently ushered in a new era for the sport.

Budweiser stores yeast derived from the original 1800s strain in a secret bunker, which only the Head of Yeast Management can access—not even the CEO

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

While the first exchange-traded fund (a 'basket' of different assets that can be bought and sold on a stock exchange) in the US only launched in 1993, the global ETF market has grown to more than $10T in the short time since.

Lesser-known phobias include turophobia, or the fear of cheese, and nomophobia, the fear of being without your cell phone.

For centuries, it was common to sleep in two shifts: a few hours at the beginning of the night, and a longer period beginning around midnight

Corals are themselves not coral reefs—the term refers to the tiny marine invertebrates that build the rigid reef.

Urushiol, the oily toxin in poison ivy, can remain allergenic on clothing for years.

Ebola is a filovirus, meaning it resembles a thread under a microscope, though it sometimes twists and can resemble a bowl of spaghetti.

The most expensive ad of all time was for Chanel No. 5 perfume and cost roughly $33M to produce in 2004—about $57M in today's dollars.

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