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Digestive System

Of the 14 athletes studied in this research, ten competed in ultramarathons and ran up to about 7,000 miles over the course of the year.

How Far Is Too Far for Ultra-Endurance Athletes? This Study of Metabolism Found Out

Individual athletes ran an average of 4,000 miles over a year to help define the human body’s limit for energy expenditure

Researchers discover the secret behind Burmese pythons' ability to fully digest the bones of their prey.

Researchers Discover the Trick That Allows Burmese Pythons to Digest the Bones of Their Prey

Special intestinal cells collect excess minerals into particles the snakes can poop out, according to a new study

The fossil find, dubbed Danekræ DK-1295, contains regurgitated fragments of sea lilies.

Cool Finds

Fossil Hunter Discovers 66-Million-Year-Old Vomit in Denmark, Offering a Clue to the Cretaceous Food Chain

A marine animal snacked on some sea lilies that did not agree with its stomach—and we now know what happened next

Two comb jellies have fused together and are being probed by a pipette.

These Frankenstein-Like Sea Creatures Can Actually Fuse Their Bodies Together

Two comb jellies can merge their digestive and nervous systems and even sync their bodily functions, according to new research. The discovery could have implications for human medicine

Viruses known known as bacteriophages, or “bacteria eaters” in Greek, occupy the gut.

Inside the Hidden Kingdom of Viruses in Your Gut

Human innards are teeming with viruses that infect bacteria. Here’s what scientists are learning about them

The bladder and the brain are involved in determining when we need to urinate.

How Do We Know When to Pee?

The basic urge is surprisingly complex and can go awry as we age

Saliva impacts how different foods taste.

How Saliva Changes the Flavor of Food

The liquid impacts how we perceive taste and can influence what we choose to eat

A 3D image of the spiral-shaped intestine of a Pacific spiny dogfish shark. In life, food would move through this intestine left to right.

Innovation for Good

Sharks’ Intestines Spiral Like a Valve Invented by Nikola Tesla

Tesla’s ingenious valve promoted a one-way flow of fluid without the need for moving parts, but, it turns out, evolution got there first

Scientists suspect that the wombat evolved this unique trait to mark its territory on rocks and logs with poop that won’t easily roll off

Wombats Poop Cubes, and Scientists Finally Got to the Bottom of It

The marsupial’s unique digestive tract forms square dung

The tough little egg made it all the way through the digestive system of a coscoroba swan like this one.

New Research

A Swan Swallowed This Fish Egg, Pooped It Out—and Then 49 Days Later, It Hatched

The new study is one of the first to demonstrate fish egg dispersal via avian fecal matter

New Research

Why Wombats Make Cube-Shaped Poos

New research shows differences in elasticity in the intestines shapes the poo as it moves through

The gut flora of dogs and humans is incredibly similar, a new study finds.

A Surprising Way Dogs Are Similar to Humans

We share more than snuggles and and a love of walks; canines and humans have similar gut microbiota

Human evolution is ongoing, and what we eat is a crucial part of the puzzle.

How Cheese, Wheat and Alcohol Shaped Human Evolution

Over time, diet causes dramatic changes to our anatomy, immune systems and maybe skin color

To find the roots of an unlikely connection, researchers are untangling lemur microbiomes. Here, ring-tailed lemurs feast at Serengeti Park in Hodenhagen, Germany.

New Research

What Lemur Guts Can Tell Us About Human Bowel Disease

Similarities between us and the cuddly primates could help us understand the origins of human illnesses—and treat them

Taste receptors for salty, sweet, bitter and sour are found all over the tongue.

The Taste Map of the Tongue You Learned in School Is All Wrong

Modern biology shows that taste receptors aren’t nearly as simple as that cordoned-off model would lead you to believe

From the tiniest to the most massive of poos, physics predicts we should all spend the same amount of time on the john.

New Research

A Grand Unified Theory of Pooping

Why you and an elephant spend the same amount of time on the john

Cool Finds

Why Coffee Makes Some People Poop

It’s not the caffeine

One group of scientists says that they've figured out a way to make rice with fewer calories.

New Research

Why Would Cooling Rice Make it Less Caloric?

Scientists suggest a new way to prepare rice that they say could help slow the worldwide obesity epidemic

This artificial ear was made on a 3D printer.

7 Medical Advances to Watch in 2014

These breakthroughs range from making body parts on a 3D printer to getting the body to fight cancer on its own