The evolution of the human brain

Why human brains were bigger 3,000 years ago

Our modern civilisation may be the most advanced to ever exist on Earth, but around 100 generations ago, our ancestors had brains that were larger than our own.

The role of fire in the evolution of humanity's big brains

Roughly 1.5 million years ago, the brain size of our hominin ancestors exploded. To understand why, Richard Wrangham posited the cooking hypothesis, arguing the adoption of fire as a means to cook food had a lasting impact on our ability to digest...

Why humans survived and smarter species did not

This interview with Joseph Henrich, a renowned professor of human evolutionary biology, unpacks human history. Henrich shares interesting information about why humans succeeded as a species (the answer isn't IQ), how cultural evolution works, why the human brain is shrinking, and how the Catholic Church played a role in the Industrial Revolution. Listen and watch for a deep dive into human evolution.

An interesting perspective on whether (and how) brain size matters in cognitive ability

Some brains are bigger than others, but what is the relevance, if any, to brain size and intelligence? This Scientific American article explores the question and offers examples. It also visually compares frontal slices of several mammals' brains, showing that humans don't necessarily have the biggest cerebrums on the block.

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.

What a tiny marine worm can tell us about our brains

Meet the amphioxus, a small eel-like animal that has a lot to teach us about brain evolution. The genetic roots of our brains can be seen in these unusual creatures. This three-minute educational video focuses on the evolutionary history of the human brain through these odd little critters with a 500-million-year-old history.

Your brain appears to age in five distinct stages

Analysis of brain scans from about 4,000 people has helped scientists identify five major stages of our brain's maturation from birth to death. The pattern of connections inside our brains seem to shift, on average, at ages 9, 32, 66 and 83. (Some readers may experience a paywall.)

Like fingerprints, brain anatomy is unique too

Researchers have discovered that a combination of experiences and genetic factors shape the anatomy of the human brain. They found even quick experiences affect the brain’s genetic makeup, which—over time—means every person develops a completely unique brain anatomy. While brain imaging could be used to identify individuals, it remains much more expensive than fingerprinting for now. Read to found out more about this study from the University of Zurich.

Is human evolution speeding up or slowing down?

In the past 3,000 years, many populations have evolved genetic adaptations to their local environments. People in Siberia and the high arctic are uniquely adapted to survive extreme cold. The Bajau people can dive 70 meters and stay underwater for almost 15 minutes. So what are other recent changes? And will our technological innovations impact our evolution?

Why do humans have such long childhoods?

Humans have over twice as long childhoods than other animals with similar lifespans like whales and elephants. A human child can grow for nearly 20 years before they become a reproducing adult. Researchers believe there's a connection between long childhoods and human's unusually large brain size, though the science is not totally clear. Dive into what scientists know here.

A beginner’s guide to the brain

Small but powerful, the brain constitutes only about 2 percent of the human body. However, it runs jus about everything, day and night, all year round. Learn about the different parts of the human brain, as well as its unique defenses, like the blood brain barrier in this four-minute video.

Language is evolution's great mystery

What we call language is something more specific than communication. Language is about sharing what’s in our minds: stories, opinions, questions, the past or future, imagined times or places, ideas. So what does language mean for humanity, and how did we come to have it? Watch this brief video to discover more.

Human anatomy provides evidence for evolution

Throughout history, scientists have used anatomy to support the Theory of Evolution in three main ways. Homologous structures, or similar physical features in organisms that serve different functions, can help scientists understand common ancestors....

Explore the human family tree

This interactive human family tree shows the various species that constitute the human evolutionary family. Click on each species or group image to learn more.

How do brain scans work?

There’s only one thing in our solar system sophisticated enough to study itself: the human brain. But this self-investigation is challenging because a living brain is shielded by skull, swaddled in tissue, and made up of billions of tiny cells. How do we study living brains without harming their owners? Two experts explain how the various techniques like EEGs, fMRIs, and PETs work in this TedEd talk.

Why humans evolved single-child pregnancies

While birthing twins has been a rare occurrence for humans, research suggests that twins were actually the norm much further back in primate evolution. It’s proposed that single-childbearing turned out to be critical for the evolution of larger babies with larger heads. Discover more about the shift that gives insight into primate evolution.

Were humans the only hominin to walk upright?

When you imagine the line human evolution has taken, you might picture the March of Progress, an image of several chimp-like ancestors marching toward the implied final form: the upright bipedal Homo sapiens. Turns out this image, popularized in the...

The evolution of dream science—from interpretation to advanced brain imaging

In the mid-1900s, dream scientists would tape study participants' eyes open, wait for them to fall asleep, and attempt to influence their dreams by shaking, tickling, and more. Now, advanced techniques like MRIs have shed new light on what’s happening in the brain as we sleep.

A brief history of artificial intelligence

The concept of artificial intelligence and what it may mean for humanity has evolved as computer technologies have grown increasingly powerful through the decades. Beginning with the first (massive) computers in the 1940s, scientists have sought to make the machines as intelligent as humans. But it wasn't until computing power made exponential gains have computers begun to imitate human behavior.

Behind the fascinating disguising mechanism of camouflage

Camouflage—nature's master game of hide-and-seek—is more complex than simply how things look. The disguising process required millions of years of evolution that have programmed how our brains take shortcuts. Watch this video to see examples of camouflage and understand how we process it.

Humans won't develop more than 5 fingers because it would impact too many body parts

All modern animals have five or fewer digits on each of their limbs. Roughly 348 million years ago, at least two species had eight: the Ichthyostega and the Acanthostega. According to Dollo's law, complex evolved features are very unlikely to recur in evolution. Researchers believe humans won't develop more than five digits because it would impact other body parts too much.

The biology of stress in your body

Stress is a normal human response that has evolved over millions of years to handle changes or threats in our environment. This article is a helpful overview of the biological basics of this response. While it is not harmful to our physiology in the acute setting, chronic stress can lead to damaging changes in the human body over many years.

Alzheimer's can lead to brain shrinkage, with an average of around 2% of volume reduction per year

Stem cells develop into a wide range of other specialized cells in the human body

Stem cells are different from other cells because they are capable of creating copies of themselves and producing other types of cells. For example, the ones found in our brains, bones, or muscles. Curious about stem cells? Here's a breakdown of how they work.

A dog's central sniffing organ is many times bigger than a human's

The olfactory epithelium, located high up within the human nose, is home to millions of olfactory neurons. A dog's olfactory epithelium is much larger—and has more neurons—than a human's, which helps to explain the animal's superior sniffing ability.

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.

Crows are believed to have intelligence on par with a seven-year-old child and demonstrate complex behaviors, from problem-solving with tools to recognizing human faces.

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

Researchers believe the brain consolidates memories, processes emotions, and plans for the future during dream states

Larger animals like giraffes, elephants, and blue whales have developed a unique defense against cancer, a phenomenon known as Peto's Paradox

Watch how algorithms can be designed to train themselves and self-improve without human input, to the point where the optimized code is too complex for programmers to understand.

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

After NASA's Voyager 1 captured Earth as a single pixel as it left the solar system in 1990, astronomer Carl Sagan used the image to reflect on humanity's fragility and the responsibility to protect 'the only world we've ever known.'

Learn how your body is, scientifically, like a firework with its own slow, controlled burn.

See the evolution of Ebola vaccine and treatment development.

Trace how the Bill of Rights, inspired by centuries of political theory, took shape between 1774 and 1789.

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.

Clever Hans was a 1900s horse that was believed to be able to solve math equations, tell time, and read and comprehend German, until a psychology student discovered how he got his answers.

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 animatronic shark from Steven Spielberg's 'Jaws,' the first modern blockbuster, was a complex underwater apparatus called 'Bruce.'

Apeirophobia is an overwhelming fear of living forever, perhaps stemming from the brain's inability to conceptualize an infinite life.

This site reaches millions of visitors who are tired of AI chatbots and seeking human connection. Pretend to be an AI chatbot and ask questions, provide answers, and draw for people in real time.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

According to the physics of black holes, our 4D reality may be a hologram—a projection of information coded on a 2D surface on the edge of the universe.

Hear about the 250-year history of the United States Postal Service, complete with some of its strangest deliveries, important innovations, and the figures that made it an American institution.

Search a massive database of over 4 decades of clues from the TV quiz show 'Jeopardy!'

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

US consumers collectively owe more than $1T to credit card companies—almost as much as they owe in auto loans.

In 2019, a laptop loaded with six of the worst malware in history and described as 'an exhibit of historical weaponry' sold for $1.3M.

Explore a list of the 100 best novels of all time, compiled by some of the world's best living writers, including Salman Rushdie, Stephen King, and Jennifer Egan.