Nature

WTF Fun Fact 13678 – Hippos Make Their Own Sunscreen

Hippos make their own sunscreen. And it’s all natural!

Sunny Hippos

Hippos spend a significant amount of time submerged in water to keep cool under the hot African sun. However, they can’t stay underwater forever. When they emerge, they’re exposed to the same UV radiation that has us humans slathering on sunscreen. But nature has equipped hippos with a remarkable solution.

Hippos secrete a reddish fluid from their skin, often referred to as “blood sweat.” But don’t be alarmed; it’s neither blood nor sweat. This secretion is unique to hippos and serves multiple purposes, including acting as a potent sunscreen. This natural sunscreen is crucial for their survival, protecting their sensitive skin from sunburn and possibly even skin infections.

The Science of “Blood Sweat”

What makes this “blood sweat” so special? It’s a combination of two distinct pigments: one red (hipposudoric acid) and one orange (norhipposudoric acid). These pigments absorb ultraviolet light, preventing damaging rays from penetrating the hippo’s skin. Moreover, this secretion is both antibacterial and antifungal, providing an all-around protective barrier for the hippo’s skin.

Researchers have studied these pigments, hoping to unlock their secrets for potential applications in human sunscreens. The idea of a sunscreen that not only protects from UV radiation but also offers antibacterial and antifungal benefits is certainly appealing.

How Hippos Make their Own Sunscreen

The hippo’s “blood sweat” isn’t just about sun protection. This secretion also helps to regulate their body temperature. As the liquid evaporates, it cools the skin, much like sweating does for humans. This is vital for an animal that spends time in both the scorching heat and the water.

This multifaceted secretion underscores the complexity of nature’s adaptations. Hippos, with their massive size and seemingly leisurely lifestyle, might not strike us as the pinnacle of evolutionary innovation. Yet, they carry within them a biochemical marvel that scientists are only beginning to understand fully.

In wrapping up this exploration into the hippo’s sunscreen, it’s clear that nature often holds the most sophisticated solutions to life’s challenges. The hippo’s ability to produce its sunscreen is a testament to the ingenuity of evolutionary adaptations, providing protection against the sun, bacterial and fungal infections, and helping regulate body temperature.

This unique adaptation not only highlights the importance of sun protection across the animal kingdom but also opens doors for scientific research. The potential applications of mimicking or harnessing the properties of the hippo’s “blood sweat” could revolutionize how we approach sunscreen and skin protection in the future.

In essence, the hippopotamus, with its hefty frame and aquatic lifestyle, is a walking, basking example of nature’s ability to find creative solutions for survival. So, the next time you reach for your bottle of sunscreen, spare a thought for the hippos, who have been basking under the African sun with their own built-in UV protection for millennia.

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Source: “How Do Some Animals Make Their Own Sunscreen?” — National Geographic

WTF Fun Fact 13674 – Sloth Facts

Everybody loves weird animal facts, but we were surprised at how much fun we had learning about these sloth facts.

Sloths, those slow-moving creatures often seen hanging from the trees of Central and South America, captivate many with their laid-back lifestyle and seemingly permanent smiles. But there’s more to these creatures than meets the eye.

Masters of the Slow Lane

First and foremost, sloths are known for their exceptionally slow movement. This deliberate pace is not just a quirk; it’s a survival strategy. By moving slowly, sloths become difficult to detect by predators such as eagles and jaguars. Their slow metabolism, suited to digesting leaves with low nutritional value, necessitates this leisurely pace.

One cool sloth fact: A sloth can take up to a month to digest a single meal!

Aquatic Sloth Facts

One of the most surprising sloth facts is their proficiency in water. Despite their arboreal lifestyle, sloths are excellent swimmers. They can hold their breath underwater for up to 40 minutes, an ability that surpasses that of many aquatic animals.

This skill is facilitated by their ability to slow their heart rates, conserving oxygen while submerged. Swimming is also the only time sloths move swiftly, using their long arms to propel themselves through water.

Furry Sloth Facts

Sloth fur is a mini-ecosystem. The greenish tint of their coats comes from algae that grow in their fur. This symbiotic relationship benefits both parties: the algae gain a place to live, and the sloths receive camouflage, blending in with the greenery of the forest.

Furthermore, the fur hosts a variety of insects and microorganisms, some of which are found nowhere else.

Sky-High Bathroom Breaks

Sloths descend from their tree-top homes about once a week to relieve themselves on the forest floor. This behavior puzzles scientists since it puts the sloth at risk of predation. One theory suggests this ritual helps maintain the ecosystem in their fur, fertilizing the algae they host. Another idea is that it aids in reproduction, allowing sloths to leave their scent on the ground for potential mates.

Built-in Umbrella

Sloths have adapted to their rainy environment in remarkable ways. Their fur grows in the opposite direction of most mammals, from their stomach to their back. This unique growth pattern allows water to run off more efficiently during rainstorms, essentially providing a built-in umbrella. This adaptation ensures sloths stay as dry as possible in their damp forest habitats.

Solitary Sloth Facts

Sloths are solitary creatures. They spend the majority of their lives alone, coming together only to mate. Even then, interactions are brief. Their solitary nature is reflected in their territorial behavior, with individual sloths having their own preferred trees and branches. Despite their isolation, sloths are not completely antisocial. Mothers are nurturing, caring for their young for months, teaching them which leaves are best to eat and how to navigate the treetops.

Night Owls of the Forest

Contrary to what one might expect, sloths are not always sleeping. Though they can sleep up to 20 hours a day, sloths are primarily nocturnal and become more active at night.

During the day, they rest in the safety of the treetops, conserving energy for their nightly activities. This nocturnal lifestyle helps sloths avoid diurnal predators and find food with less competition.

Pretty cool, right? Who knew?!

— WTF fun facts

Source: “A Sloth Can Hold Its Breath for 40 Minutes Underwater — and 6 Other Facts For International Sloth Day” — Travel + Leisure

WTF Fun Fact 13673 – Clouds Are Heavy

Did you know that clouds are heavy?

Yep, those fluffy, floating fixtures in the sky, hold a heavy secret. It’s a surprising fact that the seemingly weightless clouds drifting above us actually carry an immense amount of water, making them far heavier than they appear.

How Heavy Are Clouds?

A single cumulus cloud, the type that looks like a giant cotton ball in the sky, can weigh as much as 1.1 million pounds. That’s equivalent to the weight of about 200 elephants. How can something so heavy float? The answer lies in the density and distribution of the cloud’s water droplets or ice crystals and the air surrounding them.

Clouds form when water vapor rises into the air and cools, condensing into tiny droplets or ice crystals. Despite their mass, clouds float because these water droplets are spread over a vast area and are less dense than dry air. When you look up at a cloud, you see millions of these tiny water droplets suspended in the atmosphere.

The Science Behind Why Clouds Are Heavy

The atmosphere is a fluid, and like all fluids, it supports objects less dense than itself. Cloud droplets are tiny, about a hundredth of a millimeter in diameter, allowing them to be kept aloft by rising air currents until they combine with other droplets to form larger ones and eventually fall as precipitation. This process is a fundamental aspect of the water cycle, redistributing water from the earth’s surface to the atmosphere and back again.

Clouds and Climate

Clouds play a crucial role in the earth’s climate system. They reflect sunlight, helping to cool the earth’s surface, and they trap heat, contributing to the greenhouse effect. The balance between these two roles depends on the type, altitude, and thickness of the clouds.

Understanding the weight and composition of clouds is crucial for climate scientists. It helps them model the earth’s climate system and predict changes in weather patterns. With climate change altering the atmosphere’s dynamics, scientists are studying clouds more intensively to understand their impact on global temperatures and weather anomalies.

The Weight of Water

To grasp the true weight of clouds, consider the water cycle. Water evaporates from the earth’s surface, rises up, cools, and condenses into clouds. A cloud’s weight comes from this water content.

The amount of water in a typical cloud is enough to fill 100 Olympic-sized swimming pools. Yet, this water is so dispersed within the cloud that it doesn’t fall to the ground until it condenses into larger droplets.

A Perspective on Precipitation

When clouds become too heavy, that’s when precipitation occurs. The process of droplets merging to become heavy enough to overcome air resistance and fall to the ground can result in rain, snow, sleet, or hail. This transition from cloud to precipitation illustrates the dynamic and ever-changing nature of our atmosphere.

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Source: How Much Does a Cloud Weigh? — U.S. Geological Survey

WTF Fun Fact 13672 – Squirrels’ Brains Get Bigger

Squirrels’ brains get bigger so they can remember where they buried their nuts. At least, that’s the theory!

The Science Behind Squirrels’ Brains Getting Bigger

Squirrels that engage in scatter-hoarding exhibit a level of methodical planning that rivals that of humans in complexity. They don’t just bury their food anywhere; they make calculated decisions on where and how to store each nut. This behavior involves assessing each nut’s weight, freshness, and potential infestation through methods like paw manipulation. Such detailed analysis requires a significant amount of cognitive processing.

Interestingly, the type of nut and its size influence how and where it’s stored. Larger nuts are buried less densely to prevent other animals from finding a jackpot. Meanwhile, smaller nuts like peanuts are scattered more broadly.

This not only showcases squirrels’ strategic planning but also their ability to categorize and organize their food sources spatially.

Squirrel Brain Change with the Seasons

The act of burying nuts isn’t just about survival through winter. This behavior is a cognitive exercise that may lead to physical changes in the brain.

Lucia Jacobs, a professor at the University of California-Berkeley, posits that the intense period of nut storage is linked to observable growth in squirrel brains. This growth isn’t permanent, however. Brain sizes fluctuate with the seasons, enlarging during the autumnal nut-gathering frenzy and reducing thereafter.

This seasonal brain change isn’t unique to squirrels!

Shrews experience a reduction in brain size to conserve energy during winter, a phenomenon known as the Dehnel effect. Unlike shrews, squirrels live much longer and thus exhibit a cyclical pattern of brain enlargement and reduction correlating with their nut-gathering activities.

Squirrels Brains Get Bigger for Memory and Survival

The cognitive demands of scatter hoarding may enhance squirrels’ spatial memory. The constant interaction with their cache, through checking and sometimes relocating nuts, helps squirrels build a mental map of their stored food. This becomes crucial in winter, when finding food quickly can mean the difference between life and death. The ability to remember the location of their food stores allows squirrels to efficiently forage in the snow, minimizing exposure to predators.

The Bigger Picture

This research into squirrel behavior and brain size opens up new avenues for understanding animal cognition and seasonal adaptations. It challenges us to reconsider the intellectual capabilities of animals and their responses to environmental pressures. The insights gained from studying squirrels could inform broader studies on memory, survival strategies, and brain plasticity across species.

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Source: “In the autumn, squirrels think about nuts so much that it may make their brains bigger” — University of Michigan

WTF Fun Fact 13655 – Ice Age Fire Art

Surviving the Ice Age required more than just hunting and gathering – there was fire art. OK, hear us out.

As they gathered around fires for warmth and safety, something more than just physical comfort emerged. This was a time for them to indulge in an artistic pursuit that continues to fascinate us today.

The Paleolithic Animator and Ice Age Fire Art

In recent research published in PLOS ONE, a team led by archaeologist Andy Needham proposed an intriguing idea. They suggested that Ice Age artists used the flickering light of fire to bring their stone carvings to life.

These 15,000-year-old limestone plaquettes, adorned with animal figures, were not just static art. Instead, under the dynamic light of a fire, they appeared to move, animating the etched creatures. Fire art!

Needham’s team studied various limestone plaquettes found at the Montastruc rock shelter in southern France. These carvings, attributed to the Magdalenian culture, showcased a range of animals like horses, ibex, and reindeer.

Interestingly, these plaquettes showed signs of thermal damage, suggesting exposure to fire. But was this intentional?

Experimental Archaeology Sheds Light

To answer this, the researchers turned to experimental archaeology. They created replica plaquettes and subjected them to different fire scenarios. These experiments aimed to replicate the pinkish discoloration seen on the originals. The results? The patterns suggested that the artworks were deliberately placed near the hearth, likely as part of the creative process.

Further exploring this idea, the team used virtual reality to simulate firelight’s effect on the plaquettes. The results were fascinating. The irregular lighting from the fire brought an illusion of movement, making the animals seem like they were alive and moving across the stone surface.

The Role of Pareidolia in Ice Age Fire Art

This phenomenon can be partly explained by pareidolia, where the human brain perceives familiar patterns in random objects. In the flickering firelight, viewers would see incomplete forms on the plaquettes. Their brains would fill in the gaps, creating a dynamic viewing experience.

The Ice Age artists might have used this to their advantage. They could start with natural rock features to shape their animals, allowing the firelight to complete the picture. This interaction between the art, the rock’s natural form, and the dynamic firelight created a captivating experience, unique to the Paleolithic era.

Beyond survival, these artistic endeavors provided a social outlet. After a day of survival tasks, our ancestors likely gathered around the fire, not just for warmth but for a communal experience. Here, they could indulge in storytelling, companionship, and artistic expression.

The act of creating art by firelight was perhaps as important as the art itself. It wasn’t just about the final product but about the process of creation, the gathering of minds, and the sharing of ideas. This communal aspect of Ice Age art adds a deeply human dimension to our understanding of these ancient peoples.

Art as a Cultural Practice

Ice Age art wasn’t merely aesthetic; it was a cultural practice imbued with meaning. The process of drawing, the summoning of spirits, and even acts of destruction (like deliberate breakage or fire damage) could have had significant roles in their society.

These artistic sessions by the firelight might have served multiple purposes – from summoning spirits to strengthening community bonds. The plaquettes, once used, could have been discarded or intentionally destroyed, suggesting a transient nature to this art form.

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Source: “Ice Age Artists May Have Used Firelight to Animate Carvings” — Smithsonian Magazine

WTF Fun Fact 13544 – What Darwin Ate

You might assume that Charles Darwin, the famed naturalist, was a vegetarian since he was so enamored with living creatures, but he was just the opposite – in fact, Darwin ate some of his discoveries.

During his journey on The Beagle, he indulged in an array of exotic meats – from puma, which he found “remarkably like veal in taste,” to armadillos and iguanas.

His curiosity even led him to taste the bladder contents of a giant tortoise. Darwin’s palate wasn’t just adventurous; it was scientific. He was known for eating specimens he was studying and trying to describe scientifically.

Modern Biologists Follow Suit

This gastronomic curiosity didn’t end with Darwin. Many modern scientists continue to eat their study subjects, either out of convenience (as with those researching edible plants and animals like trout or blueberries) or driven by sheer curiosity. From bluegill and sea urchin to more peculiar choices like beetles and cicadas, the range of their dietary experiments is vast.

Notably, Richard Wassersug, while conducting a study on the palatability of tadpoles in the 1970s, had graduate students (bribed with beer) taste but not swallow various tadpole species. This experiment, now impossible to conduct due to ethical restrictions, showed that easy-to-catch tadpoles often tasted worse. Wassersug himself described the taste of toad tadpoles as “astonishingly bitter.”

The Drive Behind Why Darwin Ate an Unusual Diet

The motivation behind these gastronomic explorations varies. Sometimes it’s an academic pursuit, as in Wassersug’s study. Other times, it’s a quest to manage invasive species, turning them from pests into menu items. Sarah Treanor Bois, during her Ph.D. research on invasive plants, attended a cook-off featuring dishes made from invasive species like nutria and bullfrog legs. Eating invasives is not just about satiating curiosity but also about drawing attention to ecological problems.

However, the most common reason cited for these unusual diets is pure scientific curiosity. Robert Thorson, a geologist, once tasted 30,000-year-old meat from a giant steppe bison found in permafrost. His verdict? It was stringy and flavorless, with a “pungent rankness.”

Scientists’ Gastronomic Adventures

Why are scientists so inclined towards tasting their research subjects? Mark Siddall, a leech expert, believes it’s about familiarity. Just as an omnivore eats chicken, beef, or pork, scientists consume what they’re familiar with. To a biologist, an organism they’ve studied extensively may not seem so different from regular food. Richard Wassersug views it as a part of being a naturalist. To fully understand and connect with nature, one must engage all senses, including taste.

It’s not just about curiosity but also about a sense of community and perhaps a bit of competitiveness among scientists. The stories of Darwin and others set a precedent, and many modern scientists feel compelled to follow in their footsteps, driven by peer or ‘beer’ pressure.

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Source: “Dining Like Darwin: When Scientists Swallow Their Subjects” — NPR

WTF Fun Fact 13542 – The Rooster’s Soundproofing

Roosters are known for their loud crowing, but what contributes to a rooster’s soundproofing so it doesn’t go deaf from its own noise?

Researchers from the University of Antwerp and the University of Ghent dove into this mystery, revealing some surprising adaptations that protect these birds from self-induced hearing loss.

Crowing Loudness: More Than Just a Wake-Up Call

The research team embarked on a mission to determine the actual loudness of a rooster’s crow. They equipped sample roosters with tiny microphones near their ears to measure the intensity of the sound. Astonishingly, they discovered that the crowing averages over 100 decibels.

To put this in perspective, that’s comparable to the noise produced by a running chainsaw.

Continuous exposure to such noise levels typically leads to deafness in humans, caused by irreversible damage to the tiny hair cells in the inner ear. Since chickens, including roosters, possess similar hair cells, the team was curious about why these birds don’t suffer hearing damage.

A Built-In Ear-Plug Mechanism for the Rooster’s Soundproofing

The key to this avian riddle lies in the rooster’s unique anatomical structure. Through micro-computerized tomography scans of the birds’ skulls, the researchers uncovered two crucial adaptations.

First, they found that a portion of the rooster’s eardrum is covered by soft tissue, significantly dampening incoming noise. More impressively, when a rooster throws its head back to crow, another piece of material acts as a natural ear-plug, covering the ear canal completely.

This ingenious mechanism functions much like a person blocking their ears to muffle sound, providing the rooster with a form of self-protection against its own deafening calls.

Another intriguing aspect of avian biology plays a role here. Unlike humans, birds possess the ability to regenerate damaged hair cells in their ears. This regenerative capability provides an additional layer of defense against potential hearing damage.

But what about the hens and chicks that are within earshot of the male’s powerful crowing? While not explicitly covered in the research, it’s commonly observed that roosters often choose elevated and distant spots for crowing. This behavior ensures maximum sound reach while maintaining a safe distance from the hens and chicks, thereby reducing their exposure to harmful noise levels.

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Source: “Why roosters don’t go deaf from their own loud crowing” — Phys.org

WTF Fun Fact 13541 – NYC’s Rat Czar


New York City has taken a significant step forward in its war against rodents by appointing Kathleen Corradi as the city’s first-ever “rat czar.”

This initiative is a part of Mayor Eric Adams’ administration’s efforts to address a major quality-of-life and health challenge. Corradi’s role involves coordinating rat reduction efforts across city government agencies, community organizations, and the private sector.

Harlem Rat Mitigation Zone and Funding

As part of this initiative, Mayor Adams also announced the Harlem Rat Mitigation Zone, backed by a $3.5 million investment for Fiscal Year 2023. This investment aims to expand and accelerate rat reduction efforts across Harlem, encompassing Community Boards 9, 10, and 11. The funding will assist in employing new staff, purchasing equipment, and implementing innovative rat mitigation techniques.

Corradi’s strategic plan to combat the rat crisis includes cutting off rats’ food sources and deploying new technologies for detection and extermination. These efforts will harness the expertise of various city agencies like the Department of Health, Parks and Recreation, Housing Authority, Department of Education, Sanitation, and Small Business Services.

The rat mitigation strategy is more than just a quality-of-life issue. It symbolizes the fight against systemic challenges that have long affected New Yorkers, especially in low-income communities and communities of color. The plan aims to provide equitable quality of life experiences for all New Yorkers.

Collaborative Approach and Public Involvement

The strategy emphasizes the importance of each New Yorker playing their part in creating a rat-free city. This includes keeping homes clean, securing trash, destroying potential rat habitats, and adhering to common-sense tips. The city plans to offer Harlem-specific rat academies, teaching residents how to prevent rat infestations on their properties.

In support of the initiative, the Mayor’s Fund to Advance New York City received a donation of over 1,000 Tomcat rodent control products. These will be used across various city locations, aiding the fight against rodent infestations.

Long-Term Vision for the Rat Czar

The appointment of a rat czar marks a new era in New York City’s approach to pest control. The long-term goal is to produce a cleaner, more livable city for future generations. This effort represents a bold and creative approach to tackle one of the city’s most persistent problems.

Kathleen Corradi brings a wealth of experience in community engagement, program development, and facility operations. Her background in science and expertise in rodent mitigation positions her to lead this challenging and crucial initiative effectively.

The Adams administration has shown its commitment to addressing quality-of-life issues through various initiatives, including the ‘Get Stuff Clean’ program. The rat czar appointment further emphasizes this commitment, aiming to make New York City a cleaner and healthier place for its residents.

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Source: “Mayor Adams Anoints Kathleen Corradi as NYC’s First-Ever ‘Rat Czar'” — NYC.gov

WTF Fun Fact 13540 – Humans and Giraffes

The anatomy of humans and giraffes shares a surprising similarity. Despite stark differences in appearance and habitat, both species possess exactly seven cervical vertebrae.

This fact offers a fascinating glimpse into the world of vertebrate evolution. It highlights how different species can evolve distinct traits while maintaining a fundamental structural blueprint.

The Seven Vertebrae Similarity

In humans, the seven cervical vertebrae are compact and support head movements like nodding and turning. Each human vertebra is relatively small, with the first two, the atlas and axis, specialized for head rotation. These vertebrae are critical for protecting the spinal cord and supporting the skull.

Giraffes, renowned for their long necks, also have seven cervical vertebrae, but each one is elongated, reaching lengths up to ten inches. This elongation facilitates their tall stature, which is essential for foraging in tall trees. Despite their length, giraffe neck vertebrae maintain flexibility, crucial for their survival in the wild.

The similarity in the number of cervical vertebrae across mammals, including humans and giraffes, suggests an evolutionary blueprint conserved over millions of years. This consistency indicates an optimal balance of neck flexibility and structural support vital across various habitats and lifestyles.

The adaptation in giraffes, where their cervical vertebrae are elongated, showcases evolution’s ability to modify certain traits to meet environmental demands while keeping the overall vertebral count unchanged.

Medical and Scientific Implications for Humans and Giraffes

Studying giraffes can offer insights into human spinal health. Understanding the mechanics of giraffe vertebrae under large physical stress could lead to better treatments and preventive measures for human spinal conditions.

Research into giraffe anatomy can contribute to veterinary sciences, offering better care and conservation strategies for these unique animals. It also adds to our understanding of vertebrate evolution and adaptation.

Ecological and Conservation Aspects

The anatomical similarities between humans and giraffes reflect the interconnectedness of the animal kingdom. This comparison underscores the importance of biodiversity and the need to understand and protect various species, each contributing uniquely to our understanding of life on Earth.

Recognizing these anatomical wonders highlights the importance of conservation efforts, especially for giraffes, which face habitat loss and declining populations in the wild.

— WTF fun facts

Source: “One Good Fact” — Encyclopedia Britannica