Human anatomy provides evidence for evolution

Explore the independent lines of evidence behind the theory of evolution

Gradual changes in organisms have been directly observed through artificial selection—humans purposely selecting organisms to breed to pass on specific traits—and in organisms with short lifespans, such as insects and microbes. Analyses of DNA and anatomical structures across different species, as well as fossil records, also reveal ancient shared ancestry consistent with natural selection.

Exploring the link between history, art, and anatomy

Throughout centuries, art has played a vital role in sharing—and furthering—scientific understanding. This largely began in 1543 when physician Andreas Vesalius worked with an artist and engraver to transform learnings from his dissections into...

Human origins 101

Learn about the over 20 early human species that belong in our family tree and how the natural selection of certain physical and behavioral traits defined what it means to be human.

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...

The evolution of the human brain

The human brain, in all its staggering complexity, is the product of millions of years of evolution. Read on to find out about brain size and intelligence, language and brain development, and more.

Evidence of cancer has been found in a 1.7-million-year-old fossil

Cancer has existed as long as humans have, with some of the earliest evidence found among fossilized bone tumors, human mummies in ancient Egypt, and ancient manuscripts. The oldest example was uncovered in a toe—millions of years old—from an ancestor of modern-day humans.

Blood evolved many times over hundreds of millions of years

The earliest evidence of a blood-like substance comes from ancient arthropods, which appear to have had copper-based blood. In the 500 million years since then, some creatures have grown to rely on other variants, such as humanity's iron-based blood.

Georges Cuvier used his knowledge of anatomy to prove extinction had occurred

Extinction had been viewed as impossible because a divine plan for the world would not rationally involve the loss of any of God’s creations. However, mammoth and mastodon bones differed from elephants’, and it seemed impossible that such creatures could be hiding elsewhere on Earth.

Human anatomy 101: the body's systems

Human life is made possible by the body's ten major systems, which maintain homeostasis by responding to incoming sensory and biochemical input. Each system must work independently and collaboratively for the body to maintain health and respond appropriately to its internal and external environments. The bones of the skeletal system, for example, give the body its shape and protect organs while also facilitating movement with the muscular system.

Explore human anatomy with these beautiful images

The Human Organ Atlas offers detailed 3D images of dozens of human organs. It was created with very bright X-rays from a particle accelerator, which is formally called a synchroton imaging method.

Air sacs and lightweight bones helped some dinosaurs grow to enormous sizes

After the Triassic extinctions, new species with birdlike anatomy evolved from smaller, early dinosaurs. This anatomy allowed for more efficient breathing and lighter skeletons, favoring the evolution of larger organisms.

Continental drift is supported by matching evidence across disconnected continents

Mesosaurus fossils are found in South America and Africa, but these freshwater creatures could not have travelled across the ocean between continents. Rock layers in the Appalachian Mountains match those seen in Europe, indicating that the mountain belts were once connected.

Men and women didn't evolve to perform segregated hunter-gatherer duties

The often-cited theory that men evolved to hunt and women evolved to gather is wrong. This article explores the origins of the "Man the Hunter" theory and the mounting evidence that undermines it. Exercise science indicates that those assigned...

A history of belly buttons, from dinosaurs to modern dogs

Could dinosaurs have had belly buttons, just like you and me? Some researchers believe they've found evidence the ancient reptiles had the cute scar, a common feature among placental mammals (but which is also found in many more kinds of animals). Dive into their peculiar findings with this fascinating video.

Explore over 46,000 pages of Charles Darwin's manuscripts

The American Museum of Natural History hosts almost 35,000 digitized folios related to evolution within the fields of botany and zoology from Darwin's Beagle voyage. High-resolution color images, geological findings, and annotated books from Darwin's personal library are also viewable.

Why portraits of Neanderthals vary so drastically

Neanderthals, humanity's long-lost genealogical cousins, are often portrayed as bumbling, hairy, cave-dwelling misogynists. But other efforts show tall, dignified creatures not too different from contemporary people. This article explores why most visual interpretations of Neanderthals are more in the service of social or political beliefs instead of science.

Everything scientists could learn by looking at your skull

Our skulls are all unique, but they also share characteristics across groups of people. In the absence of fingerprints, forensic scientists can learn a lot about you just from your skull.

The science of symmetry | The Royal Society

Nature is full of symmetries, from spiral galaxies to florets of broccoli. So why do complex creatures break the pattern?This short video discusses why symmetry came to dominate life on Earth, and how many complex life forms, such as humans, transitioned from radial to lateral symmetry.

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.

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.

Model organisms like yeast, mice, and flies help scientists decode the human body

Some species are used to quickly study the effects of human diseases and treatments because they are short-lived and have similar systems to those found in humans. Bacteria, like E. coli, have been used as human proxies given their rapid growth and ease of genetic manipulability.

You can sign up to donate your body to science

It's a separate process to donate your body for medical research; you usually must contact a whole-body donation program directly. Bodies can be donated for medical research, for forensic analysis research, or for medical students to work with as they learn anatomy and surgery, among other purposes. Learn more about numerous accredited organizations that provide human bodies, organs, and tissues to medical researchers and students.

What's the point of archaeology?

Archaeology as a science may seem focused on tangible goods, with its emphasis on material evidence of peoples long passed. But its findings influence how humans interact today (and possibly tomorrow). From understanding and improving on concrete to...

'Artificial embryos': The hidden steps in forming a spine

Somitogenesis is the process by which segmented body structures like vertebrae form in embryos. While the process is well understood in animals like mice or zebrafish it is difficult to study in humans. But now, researchers have created a model of somitogenesis, using pluripotent stem cells, called an axioloid.

Around 5 million of our 3 billion DNA letters differ between individuals

Genetic testing examines gene variants to help explain disease symptoms. It explores how genetic differences between individuals can be used to understand risks of developing diseases like Huntington's Disease or passing variants linked to disease onto offspring.

Modern bodybuilding evolved in the 19th century

The origins of modern progressive resistance exercise are traced to ancient Greece, where a repeat Olympic victor carried a calf every day until it grew into a full-sized ox. This 56-minute comedy and history podcast journeys through the rise of modern bodybuilding, which took off during the 19th century.

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

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

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

The concept of phantom limbs, the perception that amputated limbs are still present, dates back to a French military surgeon in the 16th century.

Watch what the Ebola virus does inside our cells and organs in order to spread and survive.

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

The first line of 'immortal' human cells, which can divide indefinitely and are used in scientific research, was nonconsensually taken from a Black woman.

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.

Fear or disgust related to clusters of holes and cracks, called trypophobia, may stem from evolutionary processes to help us avoid pathogens.

Some Pokémon have been named after real and fictional organisms, while some real-world species have been named after Pokémon, such as Chilicola charizard and Binburrum zapdos.

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

The US Constitution is widely regarded as the longest-standing written national constitution still in force—see how it has influenced rights worldwide.

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

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

20,000 letters to the advice columnist 'Dear Abby' provide insight into prevailing sex, religion, and LGBTQ fears, anxieties, and concerns from the 1950s onward.

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.

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.

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

After her fellow cult members tried to kill her with an LSD-infused hamburger, one member of the Manson Family, the murderous cult led by Charles Manson, decided to testify against the group's leader.

The Brothers Grimm were lawyers before they were storytellers, but became interested in fairy tales as they began investigating how rules and customs had been passed down through cultures.

Hear 50 years of iconic hip-hop samples, the genre's foundational looped tracks

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.

SpongeBob exemplifies Aristotle's philosophy for living well because he understands that happiness doesn't come from external factors like money, recognition, or power.

'Grand Canyon of the Yellowstone,' a work by American painter Thomas Moran, inspired Congress to establish Yellowstone National Park.