The harsh desert environment is known for its scorching temperatures and scarcity of water, making it a challenging place for most creatures to thrive. However, amidst this seemingly inhospitable landscape, the kangaroo rat stands out as a remarkable example of nature's ingenious adaptations. These small rodents have not only managed to survive but thrive in the desert with virtually no drinking water. The secret to their survival lies in their unique physiological features, particularly their kidneys' specialized structure.

Generally, the majority of water reabsorption in the kidneys occurs in the loop of Henle (see illustration). This structure is responsible for the reabsorption of water and essential ions from the urine back into the bl ...

Despite slang terms that imply otherwise, the human penis contains no bones. The same cannot be said for many of our closest evolutionary relatives: Chimpanzees and bonobos both have penis bones (a macaque one is pictured, left), also known as bacula.

To find out why some primates have the feature whereas others don’t, researchers traced the bone’s evolutionary history through time. The baculum first evolved between 145 million and 95 million years ago, as reported in the Proceedings of the Royal Society B. That means it was present in the most recent common ancestor of all primates and carnivores. Why some descendants, like humans, lost their bacula appears to be due to differences in mating practices: In primates, the presence of a penis ...

As soon as we're born, we're destined to age. Some of us age gracefully - we enjoy years of youthfulness - while others experience hair loss, wrinkles, and greying earlier than expected.

Found in the core of each hair, a pigment known as melanin gives rise to a person's hair color. This universal pigment is also found in our skin and eyes, giving use our unique physical traits. Dark and light versions of melanin - eumelanin and phaeomelanin, respectively - combine in various combinations to create all natural hair colors.

Melanin itself is the product of a specialized cell, the melanocyte, which is found in each hair follicle, from which the hair grows. As hair grows, the melanocyte injects melanin into the hair cells, which contain the s ...

This is what an eye looks like after keratoprosthesis: a surgical procedure where a diseased cornea is replaced with an artificial cornea.

We've all struggled trying to shove magnanimous amounts of information for exams, be it vocabulary, geometry theorems, biology notes, chemistry reactions, physics equations or even just names of acquaintances we meet at weddings or the likes.  You might question whether after many years of non-stop learning, be it in a classroom setting, or just basic interactions and do's and don'ts, may we run out of space to absorb all the memories, events and information we encounter.

Our brain, unlike the brains of animals and lower ancestors, is not hardwired by instincts. In fact, we have very little in the field of instincts by comparison. Our brain is a learning brain. It is designed to absorb and interconnect information. Now, which of this inform ...

Ever seen an egg cracked underwater?

A simplified illustration of the various brain functions...

Charles Darwin said that it was "absurd in the highest possible degree".

This is the semi-transparent eyelid of the red-eyed tree frog, Agalychnis Callidryas. Frogs aren't the only creatures with 'third eyelids' that keep their eyes moist without blocking vision completely. Sharks, cats, crocodiles, polar bears and camels have them too.

Watch as a neurosurgeon opens up a patient's skull and clears the clotted blood from the surface of her brain. We probably don't have to tell you that this is extremely graphic footage, but - you've been warned.

Lungs have 'taste buds' which can detect bitter-tasting compounds, although aren't connected to the brain! The taste receptors in the lungs are the same as those in the mouth except they are not found in clusters and do not send any signals to the brain.

Right now, people with pacemakers need to go into surgery every time the battery dies. But this new pacemaker is based on the mechanics of a self-winding wristwatch, drawing all its power from the patient's beating heart.

This is what all the white matter in your brain looks like. This complex 3D-printed model accurately reflects the 2,000 strands of nerve cells that branch through every human being's brain.

Crabeater seal teeth are probably the strangest in the entire animal kingdom. The odd shapes work as a sieve, filtering out microscopic organisms (the seals' main food source) from sea water.

A viscous fluid made out of citrate and water is what gives our bones flexibility. The gooey fluid is trapped between the tiny crystals of calcium phosphate that form our bones, absorbing shocks and allowing movement. Without this fluid the crystals fuse together and become less flexible and brittle.

Men’s noses are 10% larger than female's.

Males generally have leaner muscles and need more oxygen for muscle growth and maintenance—and larger noses mean more oxygen can be breathed. A new study found that the difference in nose size between males and females of European descent starts showing in early puberty, when 95% of body weight gain in males comes from fat-free mass, compared to 85% in females.

With up to one million hairs per square inch of its body, the sea otter has the densest fur in the animal kingdom. (To put this in perspective, you’ve probably only got 100,000 hairs or less on your whole head!) Together with a huge lung capacity, this makes these water-loving creatures extremely buoyant. The pups are born so buoyant, they're incapable of diving underwater, and are often left bobbing on the surface in a sea kelp bed while their mothers hunt for food nearby.

New research has shown that liver genes play a key role in regulating our body clock, and could be the target for treatments that help shift workers and international travellers 'reset' their internal rhythm and reduce their risk of obesity and diabetes.

Pupula duplex - commonly called double pupil - is a rare medical condition, in which one's eye or eyes has two pupils.

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